Physics Book - User contributions [en]

Charged Conductor and Charged Insulator

2017-11-26T01:03:49Z

Awhite68:

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

[[File:Charging tape.png|thumb|Charges on strips of tape as they are pulled apart from http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging]]

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged.

[[File:Charging induction.png|thumb|Charging two neutral conductors by induction from http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging]]

Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

[[File:Insulator and conductor.png|thumb|Charging an insulator vs charging a conductor from http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging]]

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
[[File:conductor1.jpg]]
[[File:conductor3.jpg]]
[[File:insulator2.jpg]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]
===Solution===
[[File:example2.jpg]]
[[File:example3insulator.jpg]]

==Connectedness==

[[File:Lightning bedning.png|thumb|Mako bending lightning to save Republic City in Avatar Legend of Korra]]

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete.

[[File:Strike1.gif]] [[File:Strike2.gif]] [[File:Strike3.gif]]

Photos from free U.S. government resource: http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Before we continue, please watch the following video to see lightning bending in action: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging
http://avatar.wikia.com/wiki/Specialized_bending_techniques
http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Charged Conductor and Charged Insulator

2017-11-26T01:00:09Z

Awhite68: /* Connectedness */

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

[[File:Charging tape.png|thumb|Charges on strips of tape as they are pulled apart]]

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged.

[[File:Charging induction.png|thumb|Charging two neutral conductors by induction]]

Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

[[File:Insulator and conductor.png|thumb|Charging an insulator vs charging a conductor]]

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
[[File:conductor1.jpg]]
[[File:conductor3.jpg]]
[[File:insulator2.jpg]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]
===Solution===
[[File:example2.jpg]]
[[File:example3insulator.jpg]]

==Connectedness==

[[File:Lightning bedning.png|thumb|Mako bending lightning to save Republic City in Avatar Legend of Korra]]

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete.

[[File:Strike1.gif]] [[File:Strike2.gif]] [[File:Strike3.gif]]

Photos from free U.S. government resource: http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Before we continue, please watch the following video to see lightning bending in action: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging
http://avatar.wikia.com/wiki/Specialized_bending_techniques
http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Charged Conductor and Charged Insulator

2017-11-26T00:59:36Z

Awhite68: /* Connectedness */

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

[[File:Charging tape.png|thumb|Charges on strips of tape as they are pulled apart]]

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged.

[[File:Charging induction.png|thumb|Charging two neutral conductors by induction]]

Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

[[File:Insulator and conductor.png|thumb|Charging an insulator vs charging a conductor]]

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
[[File:conductor1.jpg]]
[[File:conductor3.jpg]]
[[File:insulator2.jpg]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]
===Solution===
[[File:example2.jpg]]
[[File:example3insulator.jpg]]

==Connectedness==

[[File:Lightning bedning.png|thumb|Mako bending lightning to save Republic City in Avatar Legend of Korra]]

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete.
[[File:Strike1.gif]] [[File:Strike2.gif]] [[File:Strike3.gif]]

Photos from free U.S. government resource: http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Before we continue, please watch the following video to see lightning bending in action: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging
http://avatar.wikia.com/wiki/Specialized_bending_techniques
http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Charged Conductor and Charged Insulator

2017-11-26T00:58:13Z

Awhite68: /* Connectedness */

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

[[File:Charging tape.png|thumb|Charges on strips of tape as they are pulled apart]]

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged.

[[File:Charging induction.png|thumb|Charging two neutral conductors by induction]]

Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

[[File:Insulator and conductor.png|thumb|Charging an insulator vs charging a conductor]]

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
[[File:conductor1.jpg]]
[[File:conductor3.jpg]]
[[File:insulator2.jpg]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]
===Solution===
[[File:example2.jpg]]
[[File:example3insulator.jpg]]

==Connectedness==

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

[[File:Lightning bedning.png|thumb|Mako bending lightning to save Republic City in Avatar Legend of Korra]]

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete.
[[File:Strike1.gif]] [[File:Strike2.gif]] [[File:Strike3.gif]]

Photos from free U.S. government resource: http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Before we continue, please watch the following video to see lightning bending in action: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging
http://avatar.wikia.com/wiki/Specialized_bending_techniques
http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Charged Conductor and Charged Insulator

2017-11-26T00:57:26Z

Awhite68: /* Connectedness */

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

[[File:Charging tape.png|thumb|Charges on strips of tape as they are pulled apart]]

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged.

[[File:Charging induction.png|thumb|Charging two neutral conductors by induction]]

Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

[[File:Insulator and conductor.png|thumb|Charging an insulator vs charging a conductor]]

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
[[File:conductor1.jpg]]
[[File:conductor3.jpg]]
[[File:insulator2.jpg]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]
===Solution===
[[File:example2.jpg]]
[[File:example3insulator.jpg]]

==Connectedness==

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

[[File:Lightning bedning.png|thumb|Mako bending lightning to save Republic City in Avatar Legend of Korra]]

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete.

[[File:Strike1.gif]] [[File:Strike2.gif]] [[File:Strike3.gif]]
Photos from free U.S. government resource: http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Before we continue, please watch the following video: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging
http://avatar.wikia.com/wiki/Specialized_bending_techniques
http://www.srh.noaa.gov/jetstream/lightning/lightning.html

File:Strike3.gif

2017-11-26T00:56:50Z

Awhite68:

File:Strike2.gif

2017-11-26T00:56:38Z

Awhite68:

Charged Conductor and Charged Insulator

2017-11-26T00:54:55Z

Awhite68:

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

[[File:Charging tape.png|thumb|Charges on strips of tape as they are pulled apart]]

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged.

[[File:Charging induction.png|thumb|Charging two neutral conductors by induction]]

Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

[[File:Insulator and conductor.png|thumb|Charging an insulator vs charging a conductor]]

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
[[File:conductor1.jpg]]
[[File:conductor3.jpg]]
[[File:insulator2.jpg]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]
===Solution===
[[File:example2.jpg]]
[[File:example3insulator.jpg]]

==Connectedness==

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

[[File:Lightning bedning.png|thumb|Mako bending lightning to save Republic City in Avatar Legend of Korra]]

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete.

[[File:Strike1.gif|http://www.srh.noaa.gov/jetstream/lightning/lightning.html]]

Before we continue, please watch the following video: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging
http://avatar.wikia.com/wiki/Specialized_bending_techniques
http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Charged Conductor and Charged Insulator

2017-11-26T00:54:10Z

Awhite68:

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

[[File:Charging tape.png|thumb|Charges on strips of tape as they are pulled apart]]

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged.

[[File:Charging induction.png|thumb|Charging two neutral conductors by induction]]

Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

[[File:Insulator and conductor.png|thumb|Charging an insulator vs charging a conductor]]

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
[[File:conductor1.jpg]]
[[File:conductor3.jpg]]
[[File:insulator2.jpg]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]
===Solution===
[[File:example2.jpg]]
[[File:example3insulator.jpg]]

==Connectedness==

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

[[File:Lightning bedning.png|thumb|Mako bending lightning to save Republic City in Avatar Legend of Korra]]

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete.

[[File:Strike1.gif|thumb|http://www.srh.noaa.gov/jetstream/lightning/lightning.html]]

Before we continue, please watch the following video: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging
http://avatar.wikia.com/wiki/Specialized_bending_techniques
http://www.srh.noaa.gov/jetstream/lightning/lightning.html

File:Strike1.gif

2017-11-26T00:52:13Z

Awhite68:

Charged Conductor and Charged Insulator

2017-11-26T00:49:51Z

Awhite68:

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

[[File:Charging tape.png|thumb|Charges on strips of tape as they are pulled apart]]

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged.

[[File:Charging induction.png|thumb|Charging two neutral conductors by induction]]

Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

[[File:Insulator and conductor.png|thumb|Charging an insulator vs charging a conductor]]

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
[[File:conductor1.jpg]]
[[File:conductor3.jpg]]
[[File:insulator2.jpg]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]
===Solution===
[[File:example2.jpg]]
[[File:example3insulator.jpg]]

==Connectedness==

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

[[File:Lightning bedning.png|thumb|Mako bending lightning to save Republic City in Avatar Legend of Korra]]

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete. Before we continue, please watch the following video: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging
http://avatar.wikia.com/wiki/Specialized_bending_techniques
http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Charged Conductor and Charged Insulator

2017-11-26T00:49:02Z

Awhite68:

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

[[File:Charging tape.png|thumb|Charges on strips of tape as they are pulled apart]]

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged.

[[File:Charging induction.png|thumb|Charging two neutral conductors by induction]]

Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

[[File:Insulator and conductor.png|thumb|Charging an insulator vs charging a conductor]]

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
[[File:conductor1.jpg]]
[[File:conductor3.jpg]]
[[File:insulator1.jpg]]
[[File:insulator2.jpg]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]
===Solution===
[[File:example2.jpg]]
[[File:example3insulator.jpg]]

==Connectedness==

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

[[File:Lightning bedning.png|thumb|Mako bending lightning to save Republic City in Avatar Legend of Korra]]

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete. Before we continue, please watch the following video: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging
http://avatar.wikia.com/wiki/Specialized_bending_techniques
http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Charged Conductor and Charged Insulator

2017-11-26T00:46:56Z

Awhite68:

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

[[File:Charging tape.png|thumb|Charges on strips of tape as they are pulled apart]]

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged.

[[File:Charging induction.png|thumb|Charging two neutral conductors by induction]]

Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

[[File:Insulator and conductor.png|thumb|Charging an insulator vs charging a conductor]]

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
[[File:conductor1.jpg|thumb|]]
[[File:conductor3.jpg|thumb|]]
[[File:insulator1.jpg|thumb|]]
[[File:insulator2.jpg|thumb|]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg|thumb|]]
===Solution===
[[File:example2.jpg|thumb|Conductor]]
[[File:example3insulator.jpg|thumb|Insulator]]

==Connectedness==

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

[[File:Lightning bedning.png|thumb|Mako bending lightning to save Republic City in Avatar Legend of Korra]]

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete. Before we continue, please watch the following video: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging
http://avatar.wikia.com/wiki/Specialized_bending_techniques
http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Charged Conductor and Charged Insulator

2017-11-26T00:43:27Z

Awhite68:

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

[[File:Charging tape.png|thumb|Charges on strips of tape as they are pulled apart]]

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged.

[[File:Charging induction.png|thumb|Charging two neutral conductors by induction]]

Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

[[File:Insulator and conductor.png|thumb|Charging an insulator vs charging a conductor]]

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==

A conductor is an object that contains mobile charges which allow an electric current to flow through the material. An object made of a conducting material will permit charge to be transferred across the entire surface of the object. If charge is transferred to the object at a given location, that charge is quickly distributed across the entire surface of the object. The distribution of charge is the result of electron movement. Since conductors allow for electrons to be transported from particle to particle, a charged object will always distribute its charge until the overall repulsive forces between excess electrons is minimized. This occurs because of the polarization within the conductor.

[[File:conductor1.jpg|thumb|]]

[[File:conductor3.jpg|thumb|]]

In contrast to conductors, insulators are materials that impede the free flow of electrons from atom to atom and molecule to molecule. If charge is transferred to an insulator at a given location, the excess charge will remain at the initial location of charging. The particles of the insulator do not permit the free flow of electrons; subsequently charge is seldom distributed evenly across the surface of an insulator.

[[File:insulator1.jpg|thumb|]]

However, the atoms within an insulator do polarize to some extent. When exposed to an electric field, the atoms will remain stationary but polarize and orient themselves with the applied field.

[[File:insulator2.jpg|thumb|]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg|thumb|]]

===Solution===

[[File:example2.jpg|thumb|Conductor]]

[[File:example3insulator.jpg|thumb|Insulator]]

==Connectedness==

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

[[File:Lightning bedning.png|thumb|Mako bending lightning to save Republic City in Avatar Legend of Korra]]

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete. Before we continue, please watch the following video: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging
http://avatar.wikia.com/wiki/Specialized_bending_techniques
http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Charged Conductor and Charged Insulator

2017-11-26T00:39:34Z

Awhite68:

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

[[File:Charging tape.png|thumb|Charges on strips of tape as they are pulled apart]]

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged.

[[File:Charging induction.png|thumb|Charging two neutral conductors by induction]]

Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

[[File:Insulator and conductor.png|thumb|Charging an insulator vs charging a conductor]]

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
===Charge on a Conductor===

Note: Please forgive the huge images. As of 4/9/17 images cannot be uploaded properly.

[[File:conductor1.jpg|thumb|]]
A conductor is an object that contains mobile charges which allow an electric current to flow through the material. An object made of a conducting material will permit charge to be transferred across the entire surface of the object. If charge is transferred to the object at a given location, that charge is quickly distributed across the entire surface of the object. The distribution of charge is the result of electron movement. Since conductors allow for electrons to be transported from particle to particle, a charged object will always distribute its charge until the overall repulsive forces between excess electrons is minimized. This occurs because of the polarization within the conductor.

[[File:conductor3.jpg|If the conductor is not spherical, surface charge density is higher where radius of curvature is smaller. (i.e on sharp points or corner of conductor.)]]

==Charge on an Insulator==

[[File:insulator1.jpg|thumb|]]
In contrast to conductors, insulators are materials that impede the free flow of electrons from atom to atom and molecule to molecule. If charge is transferred to an insulator at a given location, the excess charge will remain at the initial location of charging. The particles of the insulator do not permit the free flow of electrons; subsequently charge is seldom distributed evenly across the surface of an insulator.

However, the atoms within an insulator do polarize to some extent. When exposed to an electric field, the atoms will remain stationary but polarize and orient themselves with the applied field.
[[File:insulator2.jpg|thumb|]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg|thumb|]]

===Solution===
[[File:example2.jpg|thumb|Conductor]]
[[File:example3insulator.jpg|thumb|Insulator]]

==Connectedness==

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

[[File:Lightning bedning.png|thumb|Mako bending lightning to save Republic City in Avatar Legend of Korra]]

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete. Before we continue, please watch the following video: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging
http://avatar.wikia.com/wiki/Specialized_bending_techniques
http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Charged Conductor and Charged Insulator

2017-11-26T00:37:10Z

Awhite68:

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

[[File:Charging tape.png|thumb|Charges on strips of tape as they are pulled apart]]

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged.

[[File:Charging induction.png|thumb|Charging two neutral conductors by induction]]

Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

[[File:Insulator and conductor.png|thumb|Charging an insulator vs charging a conductor]]

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
===Charge on a Conductor===

Note: Please forgive the huge images. As of 4/9/17 images cannot be uploaded properly.

[[File:conductor1.jpg]]
A conductor is an object that contains mobile charges which allow an electric current to flow through the material. An object made of a conducting material will permit charge to be transferred across the entire surface of the object. If charge is transferred to the object at a given location, that charge is quickly distributed across the entire surface of the object. The distribution of charge is the result of electron movement. Since conductors allow for electrons to be transported from particle to particle, a charged object will always distribute its charge until the overall repulsive forces between excess electrons is minimized. This occurs because of the polarization within the conductor.

[[File:conductor3.jpg|If the conductor is not spherical, surface charge density is higher where radius of curvature is smaller. (i.e on sharp points or corner of conductor.)]]

==Charge on an Insulator==

[[File:insulator1.jpg]]
In contrast to conductors, insulators are materials that impede the free flow of electrons from atom to atom and molecule to molecule. If charge is transferred to an insulator at a given location, the excess charge will remain at the initial location of charging. The particles of the insulator do not permit the free flow of electrons; subsequently charge is seldom distributed evenly across the surface of an insulator.

However, the atoms within an insulator do polarize to some extent. When exposed to an electric field, the atoms will remain stationary but polarize and orient themselves with the applied field.
[[File:insulator2.jpg]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]

===Solution===
[[File:example2.jpg|Conductor]]
[[File:example3insulator.jpg|Insulator]]

==Connectedness==

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

[[File:Lightning bedning.png|thumb|Mako bending lightning to save Republic City in Avatar Legend of Korra]]

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete. Before we continue, please watch the following video: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging
http://avatar.wikia.com/wiki/Specialized_bending_techniques
http://www.srh.noaa.gov/jetstream/lightning/lightning.html

File:Lightning bedning.png

2017-11-26T00:35:40Z

Awhite68:

Charged Conductor and Charged Insulator

2017-11-26T00:34:02Z

Awhite68:

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

[[File:Charging tape.png|thumb|Charges on strips of tape as they are pulled apart]]

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged.

[[File:Charging induction.png|thumb|Charging two neutral conductors by induction]]

Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

[[File:Insulator and conductor.png|thumb|Charging an insulator vs charging a conductor]]

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
===Charge on a Conductor===

Note: Please forgive the huge images. As of 4/9/17 images cannot be uploaded properly.

[[File:conductor1.jpg]]
A conductor is an object that contains mobile charges which allow an electric current to flow through the material. An object made of a conducting material will permit charge to be transferred across the entire surface of the object. If charge is transferred to the object at a given location, that charge is quickly distributed across the entire surface of the object. The distribution of charge is the result of electron movement. Since conductors allow for electrons to be transported from particle to particle, a charged object will always distribute its charge until the overall repulsive forces between excess electrons is minimized. This occurs because of the polarization within the conductor.

[[File:conductor3.jpg|If the conductor is not spherical, surface charge density is higher where radius of curvature is smaller. (i.e on sharp points or corner of conductor.)]]

==Charge on an Insulator==

[[File:insulator1.jpg]]
In contrast to conductors, insulators are materials that impede the free flow of electrons from atom to atom and molecule to molecule. If charge is transferred to an insulator at a given location, the excess charge will remain at the initial location of charging. The particles of the insulator do not permit the free flow of electrons; subsequently charge is seldom distributed evenly across the surface of an insulator.

However, the atoms within an insulator do polarize to some extent. When exposed to an electric field, the atoms will remain stationary but polarize and orient themselves with the applied field.
[[File:insulator2.jpg]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]

===Solution===
[[File:example2.jpg|Conductor]]
[[File:example3insulator.jpg|Insulator]]

==Connectedness==

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete. Before we continue, please watch the following video: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging
http://avatar.wikia.com/wiki/Specialized_bending_techniques
http://www.srh.noaa.gov/jetstream/lightning/lightning.html

File:Insulator and conductor.png

2017-11-26T00:32:55Z

Awhite68:

Charged Conductor and Charged Insulator

2017-11-26T00:30:54Z

Awhite68:

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

[[File:Charging tape.png|thumb|Charges on strips of tape as they are pulled apart]]

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged. This is all illustrated in the figure below. Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

[[File:Charging induction.png|thumb|Charging two neutral conductors by induction]]

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
===Charge on a Conductor===

Note: Please forgive the huge images. As of 4/9/17 images cannot be uploaded properly.

[[File:conductor1.jpg]]
A conductor is an object that contains mobile charges which allow an electric current to flow through the material. An object made of a conducting material will permit charge to be transferred across the entire surface of the object. If charge is transferred to the object at a given location, that charge is quickly distributed across the entire surface of the object. The distribution of charge is the result of electron movement. Since conductors allow for electrons to be transported from particle to particle, a charged object will always distribute its charge until the overall repulsive forces between excess electrons is minimized. This occurs because of the polarization within the conductor.

[[File:conductor3.jpg|If the conductor is not spherical, surface charge density is higher where radius of curvature is smaller. (i.e on sharp points or corner of conductor.)]]

==Charge on an Insulator==

[[File:insulator1.jpg]]
In contrast to conductors, insulators are materials that impede the free flow of electrons from atom to atom and molecule to molecule. If charge is transferred to an insulator at a given location, the excess charge will remain at the initial location of charging. The particles of the insulator do not permit the free flow of electrons; subsequently charge is seldom distributed evenly across the surface of an insulator.

However, the atoms within an insulator do polarize to some extent. When exposed to an electric field, the atoms will remain stationary but polarize and orient themselves with the applied field.
[[File:insulator2.jpg]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]

===Solution===
[[File:example2.jpg|Conductor]]
[[File:example3insulator.jpg|Insulator]]

==Connectedness==

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete. Before we continue, please watch the following video: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

http://p3server.pa.msu.edu/coursewiki/doku.php?id=184_notes:charging_discharging
http://avatar.wikia.com/wiki/Specialized_bending_techniques
http://www.srh.noaa.gov/jetstream/lightning/lightning.html

File:Charging induction.png

2017-11-26T00:29:31Z

Awhite68:

File:Charging tape.png

2017-11-26T00:22:19Z

Awhite68:

Charged Conductor and Charged Insulator

2017-11-26T00:19:50Z

Awhite68: /* Charging by Induction */

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about '''using a charged object to separate mobile charged particles between two other neutral objects in contact with one another'''. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged. This is all illustrated in the figure below. Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
===Charge on a Conductor===

Note: Please forgive the huge images. As of 4/9/17 images cannot be uploaded properly.

[[File:conductor1.jpg]]
A conductor is an object that contains mobile charges which allow an electric current to flow through the material. An object made of a conducting material will permit charge to be transferred across the entire surface of the object. If charge is transferred to the object at a given location, that charge is quickly distributed across the entire surface of the object. The distribution of charge is the result of electron movement. Since conductors allow for electrons to be transported from particle to particle, a charged object will always distribute its charge until the overall repulsive forces between excess electrons is minimized. This occurs because of the polarization within the conductor.

[[File:conductor3.jpg|If the conductor is not spherical, surface charge density is higher where radius of curvature is smaller. (i.e on sharp points or corner of conductor.)]]

==Charge on an Insulator==

[[File:insulator1.jpg]]
In contrast to conductors, insulators are materials that impede the free flow of electrons from atom to atom and molecule to molecule. If charge is transferred to an insulator at a given location, the excess charge will remain at the initial location of charging. The particles of the insulator do not permit the free flow of electrons; subsequently charge is seldom distributed evenly across the surface of an insulator.

However, the atoms within an insulator do polarize to some extent. When exposed to an electric field, the atoms will remain stationary but polarize and orient themselves with the applied field.
[[File:insulator2.jpg]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]

===Solution===
[[File:example2.jpg|Conductor]]
[[File:example3insulator.jpg|Insulator]]

==Connectedness==

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete. Before we continue, please watch the following video: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

Charge Transfer

2017-11-26T00:18:28Z

Awhite68:

claimed by Lzhang375

If a charged conductor comes in contact, or is in close enough proximity, with another conductor, it is possible to transfer this charge to the second conductor. This process is called '''charge transfer'''. Charges cannot be created or destroyed; this is known as the ''Law of Conservation of Charge''. Therefore, in the transfer of charge between two objects, the amount of charge gained by one object is equal to the amount of charge loss by the other. There are multiple ways that charge can be transferred such as through direct contact and through inductance.

==Insulators vs Conductors==

In an '''insulator''', electrons are bounded tightly to atoms, which prevents charged particles from moving through the material. If charge is transferred to an insulator at a given location, the charge will remain at the location that the transfer occurred.

[[File:inschargedist.gif|thumb|180px|Charges transferred to an insulator remains at the location of transfer.]]

On the other hand, electrons are able to flow freely from particle to particle within '''conductors'''. When charge is transferred to a conductor, the charge is distributed evenly across the surface of the object via ''electron movement''. The electrons will be distributed until the repelling force between the excess electrons is minimized. This is the main difference between insulators and conductors: insulators do not have mobile charged particles whereas conductors have mobile charged particles that allow for charge transfer through the free movement of electrons. Examples of insulators include rubber and air and examples of conductors include metals and salt water.

==Transfer Charges by Conduction==

Electrons move from one object to another (especially with metals) through points of contact. An example of this is rubbing a glass rod with silk. The glass rod will become positively charged and the silk will become negatively charged; this means that electrons were transferred from the glass rod to the silk, since protons are not removed from the nuclei. Rubbing two objects together is not necessary for charge transfer, but because rubbing creates more points of contact between two objects, it facilitates charge transfer.

[[File:Conductiontransfer.gif]]

==Transfer Charges by Induction==

Unlike the transfer of charges by conduction, objects that becomes charged to each other do not require points of contact. When an object is charged, it has an electric field. This electric field will repel or attract electrons in another object. This electron movement is called transfer of charges by induction. A neutral object can be charged by another charged object through a process called '''polarization'''. This is when electrons in the object is repelled or attracted to one side of the object by the charged second object. For example, if a negatively charged sphere is placed near a neutral sphere, the electrons in the neutral sphere will be repelled by the charged sphere. The neutral sphere is now polarized, with one side of it being negatively charged and the other side being positively charged. The negatively charged side of the sphere can be removed through grounding or with a conductor. Once removed, the originally neutral sphere will now be positively charged. Another example of induction is the balloon and black pepper experiment. A balloon can be given a negative charge by rubbing it on hair. When the balloon is placed near grounded black pepper, the black pepper particles will be polarized so that it becomes positively charged on top and will be attracted to the negatively charged balloon.

[[File:Indtransfer.gif]]

== See also ==

http://www.physicsbook.gatech.edu/Charge_Motion_in_Metals

http://www.physicsbook.gatech.edu/Polarization

==References==

Internet resources on this topic:

http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators

http://www.physicsclassroom.com/class/estatics/Lesson-1/Charge-Interactions

Chabay, Ruth W., Bruce Sherwood. Matter and Interactions, Volume II: Electric and Magnetic Interactions, 4th Edition. Wiley, 19/2015. VitalBook file.

[[Category:Which Category did you place this in?]]

Charged Conductor and Charged Insulator

2017-11-26T00:17:56Z

Awhite68:

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

==Introduction==

Okay – so we know that '''charged particles''' exist out there (shout out to those positrons and electrons for being “lit” when they annihilate) and that objects can either be negatively charged, positively charged, or neutral depending on the ratio of charged particles that object has. For example, if I happen to observe some random thing in nature that has 5 protons and 4 electrons – that thing has a net charge of +1. But what we haven’t really explored '''''how something''''' (like a '''conductor''' or an '''insulator''') '''''becomes positively, negatively, or neutrally charged''''' or '''''what happens when something becomes charged'''''. Guess what? That’s what this wiki is about! And by the time you’ve finished reading this, you should have a better understanding of how one can become “charged up” (in the context of E&M physics, not in the context of 6 Gawd Drizzy Drake preparing to release the hottest diss track of the decade in response to “twitter-finger” beef initiated by former rapper Meek Mill in the Summer of 2015).

==The Main Idea==

Okay so remember in that short description above when I bolded and italicized the phrase “how something can become positively, negatively, or neutrally charged”? That processes by which this can occur are called '''charging''' and '''discharging'''. The definitions are simple: charging – how an object becomes positively or negatively charged; discharging – how a positively or negatively charged object becomes neutral. What happens to an object as a result of charging or discharging depends on the nature of that object and whether or not the object is a conductor or an insulator. All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator. But before we go further into the specifics regarding conductors and insulators, let us further discuss the means by which charging can occur: '''conduction''' and '''induction'''. Both processes involve objects becoming charged by exchanging, gaining, or losing mobile charged particles. In most examples, objects will become charged by gaining or losing electrons, but that is not always the case – other mobile charged particles can contribute to an objects net charge, such as mobile potassium or sodium ions.

==Charging by Conduction==

Okay, so y’all remember that example in lecture where the professor kept pulling tape apart? And the lab that followed up afterwards? That’s what charging by induction is all about! (No worries if you don’t remember or if you haven’t gotten to that part of the course yet – I’m not gonna leave you hanging and just assume you know and/or remember what that was all about. I gotcha back homie! Checkout this link: https://www.youtube.com/watch?v=O7siDnbEuko

As illustrated in the pulling tape exercise, charging by conduction is all about '''making contact in order to transfer charged particles'''. When the two strips of tape are quickly ripped apart, mobile charged particles (such as electrons) are transferred from one strip of tape to the other – leaving one strip positively charged and the other strip negatively charged. What mobile charged particles are transferred (such as electrons) and where those mobile charged particles go depends on chemical makeup of the materials involved in the process of charging by conduction. For example, when one is charging by conduction with plastic and wool – the plastic gains electrons to become negatively charged. But when one is charging by conduction using plastic and silk, the plastic loses electrons to become positively charged.

==Charging by Induction==

Charging by induction is all about using a charged object to separate mobile charged particles between two other neutral objects in contact with one another. First, the two neutral objects are in physical contact with each other outside the presence of the charged object. Next, the two objects are subject to the presence of a charged object, causing mobile charged particles to separate among the two connected objects, resulting in excess charge building up on the opposing surfaces of the two connected objects. Then, the two connected objects are separated while still subject to the presence of the charged object. Finally, the separated objects removed from the presence of the charged object and the excess charges distribute across the entire surfaces of each object, resulting in what were initially two neutral objects now being charged. This is all illustrated in the figure below. Here's a video that might also help explain charging by induction: https://www.youtube.com/watch?v=cMM6hZiWnig

==Discharging==

Discharging is the opposite of charging: the process by which charged objects lose their excess charge and become neutral. There are a number of ways in which charged objects can discharge. For example, charged tape can be discharged by water in the surrounding environment (over time) or by using your finger and touching the tape. When we touch charged tape, our bodies act as electrical grounds. An electrical ground is huge pool of charged particles that remains neutral when small amounts of charged particles are added or taken away

==Charging Insulators==

Insulators can only be charged by conduction. When an insulator is charged by conduction, the charged particles remain at the initial point of contact throughout time until the insulator is discharged.

When a charged object enters the immediate region of an insulator, the result is polarization of the atoms and molecules within the insulator as seen in the example below (only while in the presence of that charged object). Since insulators impede the movement of charged particles, two insulators cannot be charged by induction in the presence of a charged object.

Here’s a neat little simulator to see how an insulator (a balloon) can become charged by conduction and see what happens afterwards:
https://phet.colorado.edu/en/simulation/balloons-and-static-electricity

==Charging Conductors==

When conductors are charged by conduction, the excess charges distribute evenly across the entire surface of the conductor over time since conductors enable charged particles to move freely.

Remember how I kept using the word “object” when describing the neutral things needed in explaining charging by induction? Yea, so those objects are always going to be conductors. So charging by induction is always charging conductors by induction.

==Examples==
===Charge on a Conductor===

Note: Please forgive the huge images. As of 4/9/17 images cannot be uploaded properly.

[[File:conductor1.jpg]]
A conductor is an object that contains mobile charges which allow an electric current to flow through the material. An object made of a conducting material will permit charge to be transferred across the entire surface of the object. If charge is transferred to the object at a given location, that charge is quickly distributed across the entire surface of the object. The distribution of charge is the result of electron movement. Since conductors allow for electrons to be transported from particle to particle, a charged object will always distribute its charge until the overall repulsive forces between excess electrons is minimized. This occurs because of the polarization within the conductor.

[[File:conductor3.jpg|If the conductor is not spherical, surface charge density is higher where radius of curvature is smaller. (i.e on sharp points or corner of conductor.)]]

==Charge on an Insulator==

[[File:insulator1.jpg]]
In contrast to conductors, insulators are materials that impede the free flow of electrons from atom to atom and molecule to molecule. If charge is transferred to an insulator at a given location, the excess charge will remain at the initial location of charging. The particles of the insulator do not permit the free flow of electrons; subsequently charge is seldom distributed evenly across the surface of an insulator.

However, the atoms within an insulator do polarize to some extent. When exposed to an electric field, the atoms will remain stationary but polarize and orient themselves with the applied field.
[[File:insulator2.jpg]]

===Example Problem===

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]

===Solution===
[[File:example2.jpg|Conductor]]
[[File:example3insulator.jpg|Insulator]]

==Connectedness==

Okay, so I’m going to get super fan boy nerdy for a second and connect what we’ve learned about charging and discharging to my favorite cartoon of all time: Avatar The Last Airbender. For those of you not familiar with this amazing series – these resources might be help create some context (I highly recommend watching the original series and the spinoff with Avatar Korra): http://www.nick.com/avatar-the-last-airbender/

Within the world of Avatar and bending, each bending art has one or more specialized bending techniques that are considered to be very rare, highly coveted skills. Lightening bending (or lightning generation) is a special technique within the art of firebending. Lightning bending is an extremely difficult technique to master, as it requires the bender to be at total peace and void of all emotion (which is why it was always impossible for Zuko to learn from Uncle Iroh because that boy had so many emotional issues – which is completely understandable considering his circumstances).

Lightning bending connects to charging and discharging in a few ways. Lightning (and lightning generation) in and of itself alone is a representation of electrical discharge. Lightning is created when two dense pools of opposite charges reach out and connect to one another, creating a channel for electrical transfer of charge that results in each pool becoming neutral once that transfer is complete. Before we continue, please watch the following video: https://www.youtube.com/watch?v=6htOzNpBJv8

So let’s break down what we see in the video and how it relates to the physics of charging and discharging. Before we even see Uncle Iroh generate visible lightning, he “charges himself” by, “separating the energies of yin and yang” (according to Avatar mythology). In other words, Uncle Iroh separates mobile negatively charged particles (yin) from mobile positively charged particles (yang) within his body and immediate surroundings to set the stage for electrical charge transfer. When the amount of charge Uncle Iroh has built up in each pool is great enough to overcome the air and his body’s insulation of electric flow, this is the moment we begin to actually see lightning. The generated pools of charge connect and create a channel where charges begin to flow between pools in order for each pool to discharge and become neutral.

So all in all, in order for a firebender to lighting bend, the bender must be adept at charging and discharging to perform the technique. Once the lighting is generated, the bender then guides the discharging electric flow of energy in a desired direction (more than likely at an opponent in order to zap them).

Note: all representations of anything related to Avatar The Last Airbender are property of Nickelodeon and they rights are reserved.

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html]

Charged Conductor and Charged Insulator

2017-11-25T23:45:19Z

Awhite68:

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator.

==Charge on a Conductor==
[[File:conductor1.jpg]]
A conductor is an object that contains mobile charges which allow an electric current to flow through the material. An object made of a conducting material will permit charge to be transferred across the entire surface of the object. If charge is transferred to the object at a given location, that charge is quickly distributed across the entire surface of the object. The distribution of charge is the result of electron movement. Since conductors allow for electrons to be transported from particle to particle, a charged object will always distribute its charge until the overall repulsive forces between excess electrons is minimized. This occurs because of the polarization within the conductor.

[[File:conductor3.jpg|If the conductor is not spherical, surface charge density is higher where radius of curvature is smaller. (i.e on sharp points or corner of conductor.)]]

==Charge on an Insulator==
[[File:insulator1.jpg]]
In contrast to conductors, insulators are materials that impede the free flow of electrons from atom to atom and molecule to molecule. If charge is transferred to an insulator at a given location, the excess charge will remain at the initial location of charging. The particles of the insulator do not permit the free flow of electrons; subsequently charge is seldom distributed evenly across the surface of an insulator.

However, the atoms within an insulator do polarize to some extent. When exposed to an electric field, the atoms will remain stationary but polarize and orient themselves with the applied field.
[[File:insulator2.jpg]]

==Examples==

Note: Please forgive the huge images. As of 4/9/17 images cannot be uploaded properly.

A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]
===Solution===
[[File:example2.jpg|Conductor]]
[[File:example3insulator.jpg|Insulator]]

==Connectedness==

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html

Charge Transfer

2017-11-24T05:07:45Z

Awhite68:

claimed by Lzhang375

'''claimed by Andrew White Fall 17'''

If a charged conductor comes in contact, or is in close enough proximity, with another conductor, it is possible to transfer this charge to the second conductor. This process is called '''charge transfer'''. Charges cannot be created or destroyed; this is known as the ''Law of Conservation of Charge''. Therefore, in the transfer of charge between two objects, the amount of charge gained by one object is equal to the amount of charge loss by the other. There are multiple ways that charge can be transferred such as through direct contact and through inductance.

==Insulators vs Conductors==

In an '''insulator''', electrons are bounded tightly to atoms, which prevents charged particles from moving through the material. If charge is transferred to an insulator at a given location, the charge will remain at the location that the transfer occurred.

[[File:inschargedist.gif|thumb|180px|Charges transferred to an insulator remains at the location of transfer.]]

On the other hand, electrons are able to flow freely from particle to particle within '''conductors'''. When charge is transferred to a conductor, the charge is distributed evenly across the surface of the object via ''electron movement''. The electrons will be distributed until the repelling force between the excess electrons is minimized. This is the main difference between insulators and conductors: insulators do not have mobile charged particles whereas conductors have mobile charged particles that allow for charge transfer through the free movement of electrons. Examples of insulators include rubber and air and examples of conductors include metals and salt water.

==Transfer Charges by Conduction==

Electrons move from one object to another (especially with metals) through points of contact. An example of this is rubbing a glass rod with silk. The glass rod will become positively charged and the silk will become negatively charged; this means that electrons were transferred from the glass rod to the silk, since protons are not removed from the nuclei. Rubbing two objects together is not necessary for charge transfer, but because rubbing creates more points of contact between two objects, it facilitates charge transfer.

[[File:Conductiontransfer.gif]]

==Transfer Charges by Induction==

Unlike the transfer of charges by conduction, objects that becomes charged to each other do not require points of contact. When an object is charged, it has an electric field. This electric field will repel or attract electrons in another object. This electron movement is called transfer of charges by induction. A neutral object can be charged by another charged object through a process called '''polarization'''. This is when electrons in the object is repelled or attracted to one side of the object by the charged second object. For example, if a negatively charged sphere is placed near a neutral sphere, the electrons in the neutral sphere will be repelled by the charged sphere. The neutral sphere is now polarized, with one side of it being negatively charged and the other side being positively charged. The negatively charged side of the sphere can be removed through grounding or with a conductor. Once removed, the originally neutral sphere will now be positively charged. Another example of induction is the balloon and black pepper experiment. A balloon can be given a negative charge by rubbing it on hair. When the balloon is placed near grounded black pepper, the black pepper particles will be polarized so that it becomes positively charged on top and will be attracted to the negatively charged balloon.

[[File:Indtransfer.gif]]

== See also ==

http://www.physicsbook.gatech.edu/Charge_Motion_in_Metals

http://www.physicsbook.gatech.edu/Polarization

==References==

Internet resources on this topic:

http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators

http://www.physicsclassroom.com/class/estatics/Lesson-1/Charge-Interactions

Chabay, Ruth W., Bruce Sherwood. Matter and Interactions, Volume II: Electric and Magnetic Interactions, 4th Edition. Wiley, 19/2015. VitalBook file.

[[Category:Which Category did you place this in?]]

Charged Conductor and Charged Insulator

2017-11-24T03:58:10Z

Awhite68:

Edited Spring 2017 by Lily Masters '''Claimed by Andrew White Fall 17'''

Note: Please forgive the huge images. As of 4/9/17 images cannot be uploaded properly.

All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator.

==Charge on a Conductor==
[[File:conductor1.jpg]]
A conductor is an object that contains mobile charges which allow an electric current to flow through the material. An object made of a conducting material will permit charge to be transferred across the entire surface of the object. If charge is transferred to the object at a given location, that charge is quickly distributed across the entire surface of the object. The distribution of charge is the result of electron movement. Since conductors allow for electrons to be transported from particle to particle, a charged object will always distribute its charge until the overall repulsive forces between excess electrons is minimized. This occurs because of the polarization within the conductor.

[[File:conductor3.jpg|If the conductor is not spherical, surface charge density is higher where radius of curvature is smaller. (i.e on sharp points or corner of conductor.)]]

==Charge on an Insulator==
[[File:insulator1.jpg]]
In contrast to conductors, insulators are materials that impede the free flow of electrons from atom to atom and molecule to molecule. If charge is transferred to an insulator at a given location, the excess charge will remain at the initial location of charging. The particles of the insulator do not permit the free flow of electrons; subsequently charge is seldom distributed evenly across the surface of an insulator.

However, the atoms within an insulator do polarize to some extent. When exposed to an electric field, the atoms will remain stationary but polarize and orient themselves with the applied field.
[[File:insulator2.jpg]]

==Example==
A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]
===Solution===
[[File:example2.jpg|Conductor]]
[[File:example3insulator.jpg|Insulator]]

==Connectedness==

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html

Charged Conductor and Charged Insulator

2017-11-24T03:48:50Z

Awhite68:

Edited Spring 2017 by Lily Masters

Note: Please forgive the huge images. As of 4/9/17 images cannot be uploaded properly.

All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator.

==Charge on a Conductor==
[[File:conductor1.jpg]]
A conductor is an object that contains mobile charges which allow an electric current to flow through the material. An object made of a conducting material will permit charge to be transferred across the entire surface of the object. If charge is transferred to the object at a given location, that charge is quickly distributed across the entire surface of the object. The distribution of charge is the result of electron movement. Since conductors allow for electrons to be transported from particle to particle, a charged object will always distribute its charge until the overall repulsive forces between excess electrons is minimized. This occurs because of the polarization within the conductor.

[[File:conductor3.jpg|If the conductor is not spherical, surface charge density is higher where radius of curvature is smaller. (i.e on sharp points or corner of conductor.)]]

==Charge on an Insulator==
[[File:insulator1.jpg]]
In contrast to conductors, insulators are materials that impede the free flow of electrons from atom to atom and molecule to molecule. If charge is transferred to an insulator at a given location, the excess charge will remain at the initial location of charging. The particles of the insulator do not permit the free flow of electrons; subsequently charge is seldom distributed evenly across the surface of an insulator.

However, the atoms within an insulator do polarize to some extent. When exposed to an electric field, the atoms will remain stationary but polarize and orient themselves with the applied field.
[[File:insulator2.jpg]]

==Example==
A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]
===Solution===
[[File:example2.jpg|Conductor]]
[[File:example3insulator.jpg|Insulator]]

==Connectedness==

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html

Electric Dipole

2017-11-24T03:26:27Z

Awhite68:

Claimed by jmorton32 (2015) and edited by Shivani (Spring 2016)
and claimed by Hyder Hasnain (Fall 2016)

==Summary==

An electric dipole is made up of two point charges that have equal but opposite electric charges and are separated by a distance. The electric field is proportional to the cube of the distance from the dipole, and is dependent on whether you’re moving along the line separating the two charges or perpendicular to it. A dipole can be created, for example, when you place a neutral atom in an electric field, because the positively-charged parts of the atom will be pulled one way, and the negatively-charged parts the other way, creating a separation of charge in the direction of the field. However, electric dipoles are not limited to just atoms. Certain molecules in nature also experience the effects of electric dipoles. A prime example of this is the molecule for water, which forms a 105 degree angle between the two hydrogens connected to the oxygen. Since the oxygen has a greater electronegativity, it pulls more strongly on the electrons shared by the oxygen and hydrogen atoms and that end of the molecule becomes more negatively charged compared to the hydrogen end. Therefore, the net electric dipole points towards the oxygen atom. Therefore, there are two Electric dipoles are particularly useful in atoms and molecules where the effects of charge separation are measurable, but the distance between the particles is too small to quantify. An electric dipole faces a force of zero in a constant electric field. However, when a dipole moment is not aligned with the electric field, the dipole is acted on by a torque, which causes rotational movement.

==Mathematical Models==

===An Exact Model===
[[File:Dipole.png|300px|thumb|An Electric Dipole]]
An electric dipole is constructed from two point charges, one at position <math>[\frac{d}{2}, 0]</math> and one at position <math>[\frac{-d}{2}, 0]</math>. These point charges are of equal and opposite charge. We then wish to know the electric field due to the dipole at some point <math>p</math> in the plane (see the figure). <math>p</math> can be considered either a distance <math>[x_0, y_0]</math> from the midpoint of the dipole, or a distance <math>r</math> and an angle <math>\theta</math> as in the diagram.

We state that the net electric field at <math>p</math> is <math>E_{net}</math> and has an x and y component, <math>E_{net_x}</math> and <math>E_{net_y}</math>. Then we can individually calculate the x and y components. First we realize that since <math>E_{net} = E_{q_+} + E_{q_-}</math>, <math>E_{net_x} = E_{q_{+x}} + E_{q_{-x}}</math>, similarly for y <math>E_{net_y} = E_{q_{+y}} + E_{q_{-y}}</math>. At this point, its worth noting that <math>E_{q_{+y}} = E_{q_+} * cos(\theta_+)</math>, where <math>\theta_+</math> is the angle from <math>q_{+}</math> to <math>p</math>.

<math>\theta_+</math> and its counterpart <math>\theta_-</math> are not known. However, we can calculate them. We know <math>\theta_+</math> is formed by a triangle with one side length <math>p_y</math> and one side length <math>p_x - \frac{d}{2}</math>. Then <math>sin(\theta_+) = \frac{p_y}{\sqrt{(p_x - \frac{d}{2})^2+p_y^2}}</math>, from which you can calculate the angle. This looks disgusting, but a close inspection shows that <math>p_y</math> is the opposite side of the triangle, and the denominator is an expression forming the hypotenuse of the triangle (<math>r_+</math>) from known quantities. A similar method shows that <math>sin(\theta_-) = \frac{p_y}{\sqrt{(p_x + \frac{d}{2})^2+p_y^2}}</math>, where once again <math>\sqrt{(p_x + \frac{d}{2})^2+p_y^2} = |\vec r_-|</math>.

We now have values for <math> d, q, \theta_+, \theta_-, \vec r_+, \vec r_-</math>. This is enough to calculate <math>E_{net}</math> in both directions. The general formula for electric field strength from a [[Point Charge]] is <math>E = \frac{1}{4\pi\epsilon_0} \frac{q}{|\vec r|^2} \hat r</math>. Then <math>|E_+| = \frac{1}{4\pi\epsilon_0} \frac{q_+}{|\vec r_+|^2}</math> and <math>|E_-| = \frac{1}{4\pi\epsilon_0} \frac{q_-}{|\vec r_-|^2}</math>. We want solely the magnitude in this case because we can calculate direction and component forces using sin and cosine. Its worth noting that we can expand <math>r_+, r_-</math> to the form in the denominator of the sine and cosine. We will use this later.

First we calculate <math>E_{net_y}</math>. <math>E_{net_y} = E_{+_y} + E_{-_y} = \frac{1}{4\pi\epsilon_0} \frac{q_+}{|\vec r_+|^2} sin(\theta_+) + \frac{1}{4\pi\epsilon_0} \frac{q_-}{|\vec r_-|^2} sin(\theta_-)</math>.

Then we combine some terms, noting that <math> q_+ = -q_-</math>. <math>E_{net_y} = \frac{q_+}{4\pi\epsilon_0} * \Bigg(\frac{1}{|\vec r_+|^2}sin(\theta_+) + \frac{-1}{|\vec r_-|^2}sin(\theta_-)\Bigg)</math>

Now it gets ugly, we expand our radii and sines. To recap, <math>sin(\theta_+) = \frac{p_y}{\sqrt{(p_x - \frac{d}{2})^2+p_y^2}}</math>, <math>sin(\theta_-) = \frac{p_y}{\sqrt{(p_x + \frac{d}{2})^2+p_y^2}}</math>, <math>|r_+| = \sqrt{(p_x - \frac{d}{2})^2 +p_y^2}</math> and <math>|r_-| = \sqrt{(p_x + \frac{d}{2})^2 +p_y^2}</math>, giving us

<math>E_{net_y} =
\frac{q_+}{4\pi\epsilon_0} *
\Bigg(
\frac{1}{
(p_x - \frac{d}{2})^2 +p_y^2
}
\frac{p_y}{\sqrt{(p_x - \frac{d}{2})^2+p_y^2}} +
\frac{-1}{
(p_x + \frac{d}{2})^2 +p_y^2
}
\frac{p_y}{\sqrt{(p_x + \frac{d}{2})^2+p_y^2}}
\Bigg)</math>

Finally we can combine more terms, the denominators of the expanded sines are the square roots of the radii. We can also pull out the negative sign.

<math>E_{net_y} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{p_y}{
\Big((p_x - \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}
-
\frac{p_y}{
\Big((p_x + \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}

\Bigg)</math> That's as simplified as possible.

Much of the derivation for the x direction is similar. The major difference is that instead of calculating the sine, opposite over hypotenuse, we want cosine, adjacent over hypotenuse. That is, where <math>sin(\theta_+) = \frac{p_y}{\sqrt{(p_x - \frac{d}{2})^2+p_y^2}}</math>, <math>cos(\theta_+) = \frac{p_x - \frac{d}{2}}{\sqrt{(p_x - \frac{d}{2})^2+p_y^2}}</math>. By using this and its counterpart for <math>\theta_-</math>, the result is that

<math>E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{p_x - \frac{d}{2}}{
\Big((p_x - \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}
-
\frac{p_x + \frac{d}{2}}{
\Big((p_x + \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}

\Bigg)</math>. These provide exact formulae for the electric field due to an electric dipole anywhere on the two-dimensional plane, and they translate easily into 3-dimensions.

==Special Cases==
We can simplify the solution for many cases

===On the Parallel Axis===
On the parallel axis, we begin with the now known formula <math>E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{p_x - \frac{d}{2}}{
\Big((p_x - \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}
-
\frac{p_x + \frac{d}{2}}{
\Big((p_x + \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}

\Bigg)</math>. Since we are on the parallel axis, we know that <math>E_{net_y} = 0</math>, and <math>p_y = 0</math>.

Simplifies to

<math>E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{p_x - \frac{d}{2}}{
\Big((p_x - \frac{d}{2})^2 \Big)^\frac{3}{2}
}
-
\frac{p_x + \frac{d}{2}}{
\Big((p_x + \frac{d}{2})^2 \Big)^\frac{3}{2}
}

\Bigg)</math>.

Then, combining exponents and reducing the fraction:
<math>E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{1}{
(p_x - \frac{d}{2})^2
}
-
\frac{1}{
(p_x + \frac{d}{2})^2
}

\Bigg)</math>.

Then, we can combine these fractions. to simplify the calculations, replace <math>\frac{d}{2}</math> with <math>a</math>.

<math>E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{1}{
(p_x - a)^2
}
-
\frac{1}{
(p_x + a)^2
}

\Bigg) =

\frac{q_+}{4\pi\epsilon_0}
\Bigg(\frac{4p_x a}{(p_x^2 + a^2)^2}
\Bigg)

=

\frac{q_+ 4 a}{4\pi\epsilon_0}
\Bigg(\frac{p_x}{(p_x^2 + a^2)^2}
\Bigg)
</math>.

This is the formula. When <math>p_x >> a</math>, we can assume that <math>p_x^2 + a^2</math> is very close to <math>p_x^2</math>. Then

<math>E_{net_x} \approx
\frac{q_+ 4 a}{4\pi\epsilon_0}
\Bigg(\frac{p_x}{(p_x^2)^2}
\Bigg) =

\frac{q_+ 4 a}{4\pi\epsilon_0}
\Bigg(\frac{p_x}{p_x^4}
\Bigg)
=
\frac{1}{4\pi\epsilon_0}
\Bigg(\frac{4 a q_+}{p_x^3}
\Bigg)</math>

===On the Perpendicular Axis===
We can do a similar simplification for the perpendicular axis. We know that <math>E_{net_y} = 0</math> because the vertical forces from both point charges cancel, leaving only horizontal forces.

<math>
E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{p_x - \frac{d}{2}}{
\Big((p_x - \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}
-
\frac{p_x + \frac{d}{2}}{
\Big((p_x + \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}

\Bigg)</math>

In this case though, <math>p_x = 0</math>

<math>
E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{- \frac{d}{2}}{
\Big(( - \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}
-
\frac{\frac{d}{2}}{
\Big((\frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}

\Bigg)</math>

Once again, we say <math>a = \frac{d}{2}</math>.

<math>
E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{-a}{
\Big(( - a)^2 +p_y^2 \Big)^\frac{3}{2}
}
-
\frac{a}{
\Big(a^2 +p_y^2 \Big)^\frac{3}{2}
}

\Bigg)
=
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{-a}{
\Big(a^2 +p_y^2 \Big)^\frac{3}{2}
}
-
\frac{a}{
\Big(a^2 +p_y^2 \Big)^\frac{3}{2}
}

\Bigg)
=\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{-2a}{
\Big(a^2 +p_y^2 \Big)^\frac{3}{2}
}
\Bigg)
</math>

And this is our result.

Once again, when <math>d</math> is much smaller than <math> p_y</math>, <math>a</math> is also small, so we can assume that the denominator is just <math>p_y</math>. This allows us to simplify the resulting equation to

<math>E_{net_x} \approx \frac{q_+}{4\pi\epsilon_0} \frac{-2a}{p_y^3} </math>

==Examples==

===Simple===

A dipole is located at the origin, and is composed of charged particles with charge <math>+e</math> and <math>-e</math>, separated by a distance <math>9 \times10^{-10}</math> along the <math>y</math> axis. The <math>+e</math> charge is on the <math>+y</math> axis. Calculate the force on a proton due to this dipole at a location <math>< 0, 0, 3 \times 10^{-8} ></math> meters.

<div class="toccolours mw-collapsible mw-collapsed">
===Click for Solution===
<div class="mw-collapsible-content">
The center of the dipole is at the origin and there is a proton along the z axis. In this case, we apply the perpendicular from of the electric field equation. In this case, since <math>r >> d</math>, we can also use an approximate solution. Therefore, we apply the formula <math>E_{net} = \frac{q}{4\pi\epsilon_0} \frac{-2a}{r^3}</math>. Since <math>a = \frac{d}{2}</math>, and r is the distance to the proton, we can plug in the values and solve for the net electric field.

<math>1.6\times 10^{-19} \times 9 \times 10^9
\frac{-9 \times 10^{-10}}
{3 \times 10^{-8^3}} = -48000 \frac{N}{C}</math> on the y axis, as a vector: <math><0, -48000, 0></math>.

However, we aren't done since we want to know the force. We know that <math>F = qE</math> and in this case, both <math>q</math>, the charge on the proton and <math>E</math>, the electric field, are known. Thus the solution is <math>-48000 \times 1.6 \times 10^{-19} = -7.68 \times 10^{-15}</math> on the y axis, or <math><0, -7.68 \times 10^{-15}, 0></math>.
</div>
</div>

===Middling===
A ball of mass <math>M</math> and radius <math>R</math> is given an unknown negative charge spread uniformly over its surface. The ball is hanging from a thread and can move freely. A distance <math>L</math> directly below the center of the ball, a small permanent dipole is oriented such that the dipole axis is parallel with the center of the ball. The dipole has a dipole moment <math>p = qs</math>, with a distance <math>s</math> between the positive and negative charges of the dipole, and a mass <math>m</math>. The positive charge of the dipole is oriented closer to the center of the ball.

a) calculate the charge on the ping-pongball to levitate the dipole

b) the dipole is turned 90 degrees clockwise, without changing its position relative to the ball, what effect does this have on the ball?

<div class="toccolours mw-collapsible mw-collapsed">

===Click for Solutions===
<div class="mw-collapsible-content">
a) Because the dipole is small, we can assume that <math> s << L </math>. We wish to find the force on the dipole such that it can equal the force due to gravity. Once again, <math>F = qE</math> since by newton's third law, for a force exerted on the ball by the dipole, there is an equal and opposite for exerted on the dipole by the ball. That is <math>F_G = F_E</math>, so <math>qE = mg</math> (where <math>g</math> is the acceleration due to gravity). Therefore, in this case we wish to find the force on the ball, meaning the electric field from the dipole and the charge on the ball, <math>Q</math>. The field from the dipole is, since we are on the parallel axis, <math>E = \frac{1}{4\pi\epsilon_0} \frac{2p}{L^3}</math>. Putting this together, we get <math>mg = |Q| \frac{1}{4\pi\epsilon_0} \frac{2p}{L^3}</math>

Solving for <math>|Q|</math>: <math>|Q| = \Bigg(\frac{1}{4\pi\epsilon_0}\Bigg)^{-1} \frac{mgL^3}{2p}</math>.

However, we know that since the positive charge of the dipole is closer to the ball, the charge on the ball must be negative to create an attractive force. <math>|Q| > 0</math>, so our final answer is <math>Q = -\Bigg(\frac{1}{4\pi\epsilon_0}\Bigg)^{-1} \frac{mgL^3}{2p}</math>

b) By rotating the dipole clockwise the direction of the electric field at the location of the ping-pong ball changes. Since the positive end of the dipole is to the right, and the negative end to the left of the dipole, the electric field from the dipole acting on the ball is oriented toward the left. However, since the ball has negative charge, this results in a force on the ball to the right.
</div>
</div>

===Concept Question===
Is it possible for a permanent electric dipole to have a net (total) charge of zero?

<div class="toccolours mw-collapsible mw-collapsed">

===Click for Solution===
<div class="mw-collapsible-content">
Permanent dipoles occur when two atoms in a molecule have a great difference in their electronegativity; one atom attracts electrons more than the other, becoming more negative, while the other atom becomes more positive. A permanent magnet, such as a bar magnet, owes its magnetism to the magnetic dipole moment of the electron. A molecule with a permanent dipole moment is called a polar molecule. A molecule is polarized when it carries an induced dipole. A non-degenerate (S-state) atom can have only a zero permanent dipole.

</div>
</div>

==Electric Field of an Electric Dipole==
The electric field of an electric dipole can be constructed as a vector sum of the point charge fields of the two charges. As can be seen in the graphics, the electric field always points towards the negative particle and points away from the positive particle. This is an important characteristic which can be used to determine which end is positive and which is negative in a dipole.

Direction of electric dipole:

[[File:dipd.gif]]

Electric Field:

[[File:edip2.gif]]

==Electric Dipole Concept Map==
This concept map illustrates the other fields and forces caused by the electric dipole.

[[File:dipolecon.gif]]

==Connectedness==
Dipoles are incredibly common in physics, chemistry, and other natural sciences. While not specific to electric dipoles, much of the mathematics taught in advanced algorithms is relevant to the study of dipoles in nature, specifically certain randomized algorithms useful in computer science can be used to effectively simulate and predict natural phenomena having to do with dipole forces and the arrangement of many dipoles. Dipoles are useful in determining the behavior of certain molecules with each other. Polar molecules can act as electric dipoles, such as the water molecule mentioned earlier. This gives polar molecules certain properties when in a solution. Dipoles are the basis for polarity in molecules, which leads to other important properties such as hydrophilicity, which is very important in industry as well as in your body. The cells in the body are surrounded by a selectively permeable membrane. The outer and inner ends of this membrane are polar, while the middle part is non polar. This polarity is very important in determining which molecules enter and exit the cells in our body and therefore how the cells maintain homeostasis. Dipoles are also very common in regards to magnets, which have several applications including Maglev trains and even metal detectors.

==History==

Electric dipoles have been understood since the mid to late 1800s. However, atomic dipoles could only be understood after the discovery of the correct model of the atom by Bohr in 1913. Based on this knowledge, atomic dipoles were used in a lot of technology. Even though electric dipoles are a newer concept, the human understanding of magnetic dipoles goes way back to the ancient Greeks who discovered magnetite, which had magnetic properties.

== See also ==

[http://www.physicsbook.gatech.edu/Magnetic_Dipole Magnetic Dipole]

===External links===

[https://en.wikipedia.org/wiki/Electric_charge Electric Charge]

[https://en.wikibooks.org/wiki/Physics_Exercises/Electrostatics Additional Dipole Derivations]

[https://en.wikipedia.org/wiki/Electric_dipole_moment Electric Dipole Moment]

[https://en.wikipedia.org/wiki/Dipole Dipole]

==References==

[http://education.jlab.org/qa/historymag_01.html Magnet History]

[https://en.wikipedia.org/wiki/Bohr_model Bohr Model]

[http://hyperphysics.phy-astr.gsu.edu/hbase/electric/diph2o.html Electric Dipole]

[[Category:Fields]]

Charged Conductor and Charged Insulator

2017-11-24T03:26:10Z

Awhite68:

Edited Spring 2017 by Lily Masters (Claimed by Andrew White Fall 2017)

Note: Please forgive the huge images. As of 4/9/17 images cannot be uploaded properly.

All materials are made of atoms that contain positive and negative charges (protons and electrons). While all materials contain these two basic units, the charge distribution patterns change depending on the microscopic behavior of the atom's movement in an electric field. These differences have created two distinct classes of materials: conductors and insulators. This article will explore the differences between a charged conductor and a charged insulator.

==Charge on a Conductor==
[[File:conductor1.jpg]]
A conductor is an object that contains mobile charges which allow an electric current to flow through the material. An object made of a conducting material will permit charge to be transferred across the entire surface of the object. If charge is transferred to the object at a given location, that charge is quickly distributed across the entire surface of the object. The distribution of charge is the result of electron movement. Since conductors allow for electrons to be transported from particle to particle, a charged object will always distribute its charge until the overall repulsive forces between excess electrons is minimized. This occurs because of the polarization within the conductor.

[[File:conductor3.jpg|If the conductor is not spherical, surface charge density is higher where radius of curvature is smaller. (i.e on sharp points or corner of conductor.)]]

==Charge on an Insulator==
[[File:insulator1.jpg]]
In contrast to conductors, insulators are materials that impede the free flow of electrons from atom to atom and molecule to molecule. If charge is transferred to an insulator at a given location, the excess charge will remain at the initial location of charging. The particles of the insulator do not permit the free flow of electrons; subsequently charge is seldom distributed evenly across the surface of an insulator.

However, the atoms within an insulator do polarize to some extent. When exposed to an electric field, the atoms will remain stationary but polarize and orient themselves with the applied field.
[[File:insulator2.jpg]]

==Example==
A neutral metal sphere enters a capacitor, as shown. Show the charge distribution on the sphere. If the sphere was instead made of plastic, show the the charge distribution.
[[File:example1capacitor.jpg]]
===Solution===
[[File:example2.jpg|Conductor]]
[[File:example3insulator.jpg|Insulator]]

==Connectedness==

While insulators are not useful for transferring charge, they do serve a critical role in electrostatic experiments and demonstrations. Conductive objects are often mounted upon insulating objects. This arrangement of a conductor on top of an insulator prevents charge from being transferred from the conductive object to its surroundings.

==See also==
*[http://www.physicsbook.gatech.edu/Charge_Transfer Charge Transfer]
*[http://www.physicsbook.gatech.edu/Insulators Insulators]
*[http://www.physicsbook.gatech.edu/Conductivity Conductivity]
*[http://www.physicsbook.gatech.edu/Polarization_of_a_conductor Polarization of a Conductor]

===External links===
[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html Explanation of why charge concentrates at a point on a conductor]

==References==
[http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators http://www.physicsclassroom.com/class/estatics/Lesson-1/Conductors-and-Insulators]

[http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html http://www.schoolphysics.co.uk/age16-19/Electricity%20and%20magnetism/Electrostatics/text/Electric_charge_distribution/index.html

Electric Dipole

2017-11-24T03:14:33Z

Awhite68:

Claimed by jmorton32 (2015) and edited by Shivani (Spring 2016)
and claimed by Hyder Hasnain (Fall 2016)

'''Claimed by Andrew White (Fall 2017)'''

==Summary==

An electric dipole is made up of two point charges that have equal but opposite electric charges and are separated by a distance. The electric field is proportional to the cube of the distance from the dipole, and is dependent on whether you’re moving along the line separating the two charges or perpendicular to it. A dipole can be created, for example, when you place a neutral atom in an electric field, because the positively-charged parts of the atom will be pulled one way, and the negatively-charged parts the other way, creating a separation of charge in the direction of the field. However, electric dipoles are not limited to just atoms. Certain molecules in nature also experience the effects of electric dipoles. A prime example of this is the molecule for water, which forms a 105 degree angle between the two hydrogens connected to the oxygen. Since the oxygen has a greater electronegativity, it pulls more strongly on the electrons shared by the oxygen and hydrogen atoms and that end of the molecule becomes more negatively charged compared to the hydrogen end. Therefore, the net electric dipole points towards the oxygen atom. Therefore, there are two Electric dipoles are particularly useful in atoms and molecules where the effects of charge separation are measurable, but the distance between the particles is too small to quantify. An electric dipole faces a force of zero in a constant electric field. However, when a dipole moment is not aligned with the electric field, the dipole is acted on by a torque, which causes rotational movement.

==Mathematical Models==

===An Exact Model===
[[File:Dipole.png|300px|thumb|An Electric Dipole]]
An electric dipole is constructed from two point charges, one at position <math>[\frac{d}{2}, 0]</math> and one at position <math>[\frac{-d}{2}, 0]</math>. These point charges are of equal and opposite charge. We then wish to know the electric field due to the dipole at some point <math>p</math> in the plane (see the figure). <math>p</math> can be considered either a distance <math>[x_0, y_0]</math> from the midpoint of the dipole, or a distance <math>r</math> and an angle <math>\theta</math> as in the diagram.

We state that the net electric field at <math>p</math> is <math>E_{net}</math> and has an x and y component, <math>E_{net_x}</math> and <math>E_{net_y}</math>. Then we can individually calculate the x and y components. First we realize that since <math>E_{net} = E_{q_+} + E_{q_-}</math>, <math>E_{net_x} = E_{q_{+x}} + E_{q_{-x}}</math>, similarly for y <math>E_{net_y} = E_{q_{+y}} + E_{q_{-y}}</math>. At this point, its worth noting that <math>E_{q_{+y}} = E_{q_+} * cos(\theta_+)</math>, where <math>\theta_+</math> is the angle from <math>q_{+}</math> to <math>p</math>.

<math>\theta_+</math> and its counterpart <math>\theta_-</math> are not known. However, we can calculate them. We know <math>\theta_+</math> is formed by a triangle with one side length <math>p_y</math> and one side length <math>p_x - \frac{d}{2}</math>. Then <math>sin(\theta_+) = \frac{p_y}{\sqrt{(p_x - \frac{d}{2})^2+p_y^2}}</math>, from which you can calculate the angle. This looks disgusting, but a close inspection shows that <math>p_y</math> is the opposite side of the triangle, and the denominator is an expression forming the hypotenuse of the triangle (<math>r_+</math>) from known quantities. A similar method shows that <math>sin(\theta_-) = \frac{p_y}{\sqrt{(p_x + \frac{d}{2})^2+p_y^2}}</math>, where once again <math>\sqrt{(p_x + \frac{d}{2})^2+p_y^2} = |\vec r_-|</math>.

We now have values for <math> d, q, \theta_+, \theta_-, \vec r_+, \vec r_-</math>. This is enough to calculate <math>E_{net}</math> in both directions. The general formula for electric field strength from a [[Point Charge]] is <math>E = \frac{1}{4\pi\epsilon_0} \frac{q}{|\vec r|^2} \hat r</math>. Then <math>|E_+| = \frac{1}{4\pi\epsilon_0} \frac{q_+}{|\vec r_+|^2}</math> and <math>|E_-| = \frac{1}{4\pi\epsilon_0} \frac{q_-}{|\vec r_-|^2}</math>. We want solely the magnitude in this case because we can calculate direction and component forces using sin and cosine. Its worth noting that we can expand <math>r_+, r_-</math> to the form in the denominator of the sine and cosine. We will use this later.

First we calculate <math>E_{net_y}</math>. <math>E_{net_y} = E_{+_y} + E_{-_y} = \frac{1}{4\pi\epsilon_0} \frac{q_+}{|\vec r_+|^2} sin(\theta_+) + \frac{1}{4\pi\epsilon_0} \frac{q_-}{|\vec r_-|^2} sin(\theta_-)</math>.

Then we combine some terms, noting that <math> q_+ = -q_-</math>. <math>E_{net_y} = \frac{q_+}{4\pi\epsilon_0} * \Bigg(\frac{1}{|\vec r_+|^2}sin(\theta_+) + \frac{-1}{|\vec r_-|^2}sin(\theta_-)\Bigg)</math>

Now it gets ugly, we expand our radii and sines. To recap, <math>sin(\theta_+) = \frac{p_y}{\sqrt{(p_x - \frac{d}{2})^2+p_y^2}}</math>, <math>sin(\theta_-) = \frac{p_y}{\sqrt{(p_x + \frac{d}{2})^2+p_y^2}}</math>, <math>|r_+| = \sqrt{(p_x - \frac{d}{2})^2 +p_y^2}</math> and <math>|r_-| = \sqrt{(p_x + \frac{d}{2})^2 +p_y^2}</math>, giving us

<math>E_{net_y} =
\frac{q_+}{4\pi\epsilon_0} *
\Bigg(
\frac{1}{
(p_x - \frac{d}{2})^2 +p_y^2
}
\frac{p_y}{\sqrt{(p_x - \frac{d}{2})^2+p_y^2}} +
\frac{-1}{
(p_x + \frac{d}{2})^2 +p_y^2
}
\frac{p_y}{\sqrt{(p_x + \frac{d}{2})^2+p_y^2}}
\Bigg)</math>

Finally we can combine more terms, the denominators of the expanded sines are the square roots of the radii. We can also pull out the negative sign.

<math>E_{net_y} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{p_y}{
\Big((p_x - \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}
-
\frac{p_y}{
\Big((p_x + \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}

\Bigg)</math> That's as simplified as possible.

Much of the derivation for the x direction is similar. The major difference is that instead of calculating the sine, opposite over hypotenuse, we want cosine, adjacent over hypotenuse. That is, where <math>sin(\theta_+) = \frac{p_y}{\sqrt{(p_x - \frac{d}{2})^2+p_y^2}}</math>, <math>cos(\theta_+) = \frac{p_x - \frac{d}{2}}{\sqrt{(p_x - \frac{d}{2})^2+p_y^2}}</math>. By using this and its counterpart for <math>\theta_-</math>, the result is that

<math>E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{p_x - \frac{d}{2}}{
\Big((p_x - \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}
-
\frac{p_x + \frac{d}{2}}{
\Big((p_x + \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}

\Bigg)</math>. These provide exact formulae for the electric field due to an electric dipole anywhere on the two-dimensional plane, and they translate easily into 3-dimensions.

==Special Cases==
We can simplify the solution for many cases

===On the Parallel Axis===
On the parallel axis, we begin with the now known formula <math>E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{p_x - \frac{d}{2}}{
\Big((p_x - \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}
-
\frac{p_x + \frac{d}{2}}{
\Big((p_x + \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}

\Bigg)</math>. Since we are on the parallel axis, we know that <math>E_{net_y} = 0</math>, and <math>p_y = 0</math>.

Simplifies to

<math>E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{p_x - \frac{d}{2}}{
\Big((p_x - \frac{d}{2})^2 \Big)^\frac{3}{2}
}
-
\frac{p_x + \frac{d}{2}}{
\Big((p_x + \frac{d}{2})^2 \Big)^\frac{3}{2}
}

\Bigg)</math>.

Then, combining exponents and reducing the fraction:
<math>E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{1}{
(p_x - \frac{d}{2})^2
}
-
\frac{1}{
(p_x + \frac{d}{2})^2
}

\Bigg)</math>.

Then, we can combine these fractions. to simplify the calculations, replace <math>\frac{d}{2}</math> with <math>a</math>.

<math>E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{1}{
(p_x - a)^2
}
-
\frac{1}{
(p_x + a)^2
}

\Bigg) =

\frac{q_+}{4\pi\epsilon_0}
\Bigg(\frac{4p_x a}{(p_x^2 + a^2)^2}
\Bigg)

=

\frac{q_+ 4 a}{4\pi\epsilon_0}
\Bigg(\frac{p_x}{(p_x^2 + a^2)^2}
\Bigg)
</math>.

This is the formula. When <math>p_x >> a</math>, we can assume that <math>p_x^2 + a^2</math> is very close to <math>p_x^2</math>. Then

<math>E_{net_x} \approx
\frac{q_+ 4 a}{4\pi\epsilon_0}
\Bigg(\frac{p_x}{(p_x^2)^2}
\Bigg) =

\frac{q_+ 4 a}{4\pi\epsilon_0}
\Bigg(\frac{p_x}{p_x^4}
\Bigg)
=
\frac{1}{4\pi\epsilon_0}
\Bigg(\frac{4 a q_+}{p_x^3}
\Bigg)</math>

===On the Perpendicular Axis===
We can do a similar simplification for the perpendicular axis. We know that <math>E_{net_y} = 0</math> because the vertical forces from both point charges cancel, leaving only horizontal forces.

<math>
E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{p_x - \frac{d}{2}}{
\Big((p_x - \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}
-
\frac{p_x + \frac{d}{2}}{
\Big((p_x + \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}

\Bigg)</math>

In this case though, <math>p_x = 0</math>

<math>
E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{- \frac{d}{2}}{
\Big(( - \frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}
-
\frac{\frac{d}{2}}{
\Big((\frac{d}{2})^2 +p_y^2 \Big)^\frac{3}{2}
}

\Bigg)</math>

Once again, we say <math>a = \frac{d}{2}</math>.

<math>
E_{net_x} =
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{-a}{
\Big(( - a)^2 +p_y^2 \Big)^\frac{3}{2}
}
-
\frac{a}{
\Big(a^2 +p_y^2 \Big)^\frac{3}{2}
}

\Bigg)
=
\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{-a}{
\Big(a^2 +p_y^2 \Big)^\frac{3}{2}
}
-
\frac{a}{
\Big(a^2 +p_y^2 \Big)^\frac{3}{2}
}

\Bigg)
=\frac{q_+}{4\pi\epsilon_0}
\Bigg(
\frac{-2a}{
\Big(a^2 +p_y^2 \Big)^\frac{3}{2}
}
\Bigg)
</math>

And this is our result.

Once again, when <math>d</math> is much smaller than <math> p_y</math>, <math>a</math> is also small, so we can assume that the denominator is just <math>p_y</math>. This allows us to simplify the resulting equation to

<math>E_{net_x} \approx \frac{q_+}{4\pi\epsilon_0} \frac{-2a}{p_y^3} </math>

==Examples==

===Simple===

A dipole is located at the origin, and is composed of charged particles with charge <math>+e</math> and <math>-e</math>, separated by a distance <math>9 \times10^{-10}</math> along the <math>y</math> axis. The <math>+e</math> charge is on the <math>+y</math> axis. Calculate the force on a proton due to this dipole at a location <math>< 0, 0, 3 \times 10^{-8} ></math> meters.

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===Click for Solution===
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The center of the dipole is at the origin and there is a proton along the z axis. In this case, we apply the perpendicular from of the electric field equation. In this case, since <math>r >> d</math>, we can also use an approximate solution. Therefore, we apply the formula <math>E_{net} = \frac{q}{4\pi\epsilon_0} \frac{-2a}{r^3}</math>. Since <math>a = \frac{d}{2}</math>, and r is the distance to the proton, we can plug in the values and solve for the net electric field.

<math>1.6\times 10^{-19} \times 9 \times 10^9
\frac{-9 \times 10^{-10}}
{3 \times 10^{-8^3}} = -48000 \frac{N}{C}</math> on the y axis, as a vector: <math><0, -48000, 0></math>.

However, we aren't done since we want to know the force. We know that <math>F = qE</math> and in this case, both <math>q</math>, the charge on the proton and <math>E</math>, the electric field, are known. Thus the solution is <math>-48000 \times 1.6 \times 10^{-19} = -7.68 \times 10^{-15}</math> on the y axis, or <math><0, -7.68 \times 10^{-15}, 0></math>.
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===Middling===
A ball of mass <math>M</math> and radius <math>R</math> is given an unknown negative charge spread uniformly over its surface. The ball is hanging from a thread and can move freely. A distance <math>L</math> directly below the center of the ball, a small permanent dipole is oriented such that the dipole axis is parallel with the center of the ball. The dipole has a dipole moment <math>p = qs</math>, with a distance <math>s</math> between the positive and negative charges of the dipole, and a mass <math>m</math>. The positive charge of the dipole is oriented closer to the center of the ball.

a) calculate the charge on the ping-pongball to levitate the dipole

b) the dipole is turned 90 degrees clockwise, without changing its position relative to the ball, what effect does this have on the ball?

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===Click for Solutions===
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a) Because the dipole is small, we can assume that <math> s << L </math>. We wish to find the force on the dipole such that it can equal the force due to gravity. Once again, <math>F = qE</math> since by newton's third law, for a force exerted on the ball by the dipole, there is an equal and opposite for exerted on the dipole by the ball. That is <math>F_G = F_E</math>, so <math>qE = mg</math> (where <math>g</math> is the acceleration due to gravity). Therefore, in this case we wish to find the force on the ball, meaning the electric field from the dipole and the charge on the ball, <math>Q</math>. The field from the dipole is, since we are on the parallel axis, <math>E = \frac{1}{4\pi\epsilon_0} \frac{2p}{L^3}</math>. Putting this together, we get <math>mg = |Q| \frac{1}{4\pi\epsilon_0} \frac{2p}{L^3}</math>

Solving for <math>|Q|</math>: <math>|Q| = \Bigg(\frac{1}{4\pi\epsilon_0}\Bigg)^{-1} \frac{mgL^3}{2p}</math>.

However, we know that since the positive charge of the dipole is closer to the ball, the charge on the ball must be negative to create an attractive force. <math>|Q| > 0</math>, so our final answer is <math>Q = -\Bigg(\frac{1}{4\pi\epsilon_0}\Bigg)^{-1} \frac{mgL^3}{2p}</math>

b) By rotating the dipole clockwise the direction of the electric field at the location of the ping-pong ball changes. Since the positive end of the dipole is to the right, and the negative end to the left of the dipole, the electric field from the dipole acting on the ball is oriented toward the left. However, since the ball has negative charge, this results in a force on the ball to the right.
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===Concept Question===
Is it possible for a permanent electric dipole to have a net (total) charge of zero?

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===Click for Solution===
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Permanent dipoles occur when two atoms in a molecule have a great difference in their electronegativity; one atom attracts electrons more than the other, becoming more negative, while the other atom becomes more positive. A permanent magnet, such as a bar magnet, owes its magnetism to the magnetic dipole moment of the electron. A molecule with a permanent dipole moment is called a polar molecule. A molecule is polarized when it carries an induced dipole. A non-degenerate (S-state) atom can have only a zero permanent dipole.

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==Electric Field of an Electric Dipole==
The electric field of an electric dipole can be constructed as a vector sum of the point charge fields of the two charges. As can be seen in the graphics, the electric field always points towards the negative particle and points away from the positive particle. This is an important characteristic which can be used to determine which end is positive and which is negative in a dipole.

Direction of electric dipole:

[[File:dipd.gif]]

Electric Field:

[[File:edip2.gif]]

==Electric Dipole Concept Map==
This concept map illustrates the other fields and forces caused by the electric dipole.

[[File:dipolecon.gif]]

==Connectedness==
Dipoles are incredibly common in physics, chemistry, and other natural sciences. While not specific to electric dipoles, much of the mathematics taught in advanced algorithms is relevant to the study of dipoles in nature, specifically certain randomized algorithms useful in computer science can be used to effectively simulate and predict natural phenomena having to do with dipole forces and the arrangement of many dipoles. Dipoles are useful in determining the behavior of certain molecules with each other. Polar molecules can act as electric dipoles, such as the water molecule mentioned earlier. This gives polar molecules certain properties when in a solution. Dipoles are the basis for polarity in molecules, which leads to other important properties such as hydrophilicity, which is very important in industry as well as in your body. The cells in the body are surrounded by a selectively permeable membrane. The outer and inner ends of this membrane are polar, while the middle part is non polar. This polarity is very important in determining which molecules enter and exit the cells in our body and therefore how the cells maintain homeostasis. Dipoles are also very common in regards to magnets, which have several applications including Maglev trains and even metal detectors.

==History==

Electric dipoles have been understood since the mid to late 1800s. However, atomic dipoles could only be understood after the discovery of the correct model of the atom by Bohr in 1913. Based on this knowledge, atomic dipoles were used in a lot of technology. Even though electric dipoles are a newer concept, the human understanding of magnetic dipoles goes way back to the ancient Greeks who discovered magnetite, which had magnetic properties.

== See also ==

[http://www.physicsbook.gatech.edu/Magnetic_Dipole Magnetic Dipole]

===External links===

[https://en.wikipedia.org/wiki/Electric_charge Electric Charge]

[https://en.wikibooks.org/wiki/Physics_Exercises/Electrostatics Additional Dipole Derivations]

[https://en.wikipedia.org/wiki/Electric_dipole_moment Electric Dipole Moment]

[https://en.wikipedia.org/wiki/Dipole Dipole]

==References==

[http://education.jlab.org/qa/historymag_01.html Magnet History]

[https://en.wikipedia.org/wiki/Bohr_model Bohr Model]

[http://hyperphysics.phy-astr.gsu.edu/hbase/electric/diph2o.html Electric Dipole]

[[Category:Fields]]