http://www.physicsbook.gatech.edu/api.php?action=feedcontributions&feedformat=atom&user=Nromer3Physics Book - User contributions [en]2026-04-29T16:23:45ZUser contributionsMediaWiki 1.42.7http://www.physicsbook.gatech.edu/index.php?title=Lenz%27s_Law&diff=31670Lenz's Law2018-04-18T22:06:13Z<p>Nromer3: </p>
<hr />
<div>'''Edited by Nicole Romer (Spring 2018)'''<br />
<br />
'''Claimed by Jenny Zang (Fall 2016)'''<br />
<br />
'''Edited by Halle Bryan (Fall 2016)'''<br />
<br />
Formulated in 1834, Lenz's Law helps determine the direction of current and the field is creates. When an induced current is generated by a change in magnetic flux, as stated by Farady's Law, the induced current will flow creating its own magnetic field that opposes the magnetic field that created it. Lenz's Law and Faraday's Law of Induction are highly connected, with the negative sign in Faraday's Law showing Lenz's Law. The current direction is important in the upholding of the conservation of energy. Lenz's Law is connected to this conservation and therefore Newton's Third Law as well. <br />
<br />
==The Main Idea==<br />
<br />
Lenz's Law makes sure that Faraday's Law follows the conservation of energy as stated by Newton's Third Law. According to Faraday's Law, any change in the magnetic field will cause an induced current (emf). Lenz's Law accounts for the direction of the induced current. The change can be caused by the strength of the magnetic field, the direction of the magnetic field, the position of a circuit, the shape of a circuit, or the orientation of a circuit. The induced magnetic field inside a loop of wires is created to keep the magnetic flux in the loop constant. Any change in magnetic flux results in an equal and opposite change in the loop which is why we use negative dB/dt. This graphic displays a basic understanding of how Lenz's Law could function in one example where the existing magnetic field is increasing:<br />
<br />
[[File:sc235.jpg]]<br />
<br />
===A Mathematical Model===<br />
<br />
Lenz's Law is mathematically modeled as part of Faraday's Law. The negative sign in the equation represents the opposing induced field. <br />
<math>\epsilon = -{\frac{d\phi}{dt}} </math> where '''<math>\epsilon</math>''' is the emf of the system and '''<math>d\phi</math>''' is the change in the magnetic field.<br />
<br />
===A Computational Model===<br />
<br />
https://www.youtube.com/watch?v=xxZenoBs2Pg This links to a video by Khan Academy that explains how Lenz's Law works through an example.<br />
<br />
https://www.youtube.com/watch?v=Vs3afgStVy4 This links to a video by Grand Illusions that displays Lenz's Law using a magnetic falling down a tube.<br />
<br />
==Examples==<br />
'''Example Using Right Hand Rule'''<br />
<br />
Use the right hand rule to find the non-coulombic electric field in the given situations.<br />
[[File:Non-Coulobmic_Fields.gif]]<br />
<br />
'''Solution'''<br />
<br />
To use the right hand rule: place your thumb in the direction of the <math> -dB </math>, then curl your fingers. The direction in which your fingers curl is the direction of the non-coulombic electric field. The non-coulombic field is represented by the pink arrows.<br />
<br />
===Simple===<br />
<br />
A solenoid has current <math> I_1 </math> flowing around it increasing from 0 to 40A. A plain loop of wire is placed around the solenoid, perpendicular to the axis of the solenoid. An emf is produced, therefore producing an <math> I_2 </math>. Are <math> I_1 </math> and <math> I_2 </math> flowing in the same direction or opposite?<br />
<br />
'''Solution'''<br />
The original current <math> I_1 </math> produced a magnetic field. In order to maintain the conservation of energy and Newton's Third Law, the magnetic field produced by <math> I_2 </math> must oppose this field. This is in accordance with Lenz's Law. Therefore, <math> I_2 </math> must oppose <math> I_1 </math> in direction.<br />
<br />
<br />
===Middling===<br />
<br />
An magnet is moving through a copper tube (velocity drawn). Find the direction of -dB/dt and the direction of the induced current. Remember to use the right hand rule.<br />
<br />
[[File:LenzLaw.jpg]]<br />
Graphic created by Nicole Romer<br />
<br />
'''Solution'''<br />
A)-y, clockwise B)+y, counterclockwise C)+y, counterclockwise D)-y, clockwise<br />
<br />
<br />
The magnetic field in this graphic is decreasing at a rate of 5.0mT/s. What is the direction of the current in the circle of wire?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
<br />
'''Solution'''<br />
The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. This is in accordance with Lenz's Law. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
===Difficult===<br />
The magnetic field is decreasing at a rate of 5.0mT/s. The radius of the loop of wire is 5.0m, and the resistance is 5 ohms. What is the magnitude and direction of the current?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
'''Solution'''<br />
<br />
To find the magnitude of the current we must first use the formula <math>\epsilon = -{\frac{d\phi}{dt}} </math> to find the <math>\epsilon</math> representing the emf of the system. We know, more specifically, that <math>\epsilon = -NAcos\theta{\frac{d\phi}{dt}} </math>. Therefore, <math>\epsilon = -1*5.0^2*\pi*1*-5*10^{-3} </math> which resolves to <math>\epsilon = .392699</math>. From there, to find the current we know that <math>I = {\frac{\epsilon}{R}}</math>. Plugging in the values we know we find, <math>I = {\frac{.392699}{5.0}} = .07854A</math>. That is the magnitude of the current. To find the direction we must use Lenz's Law. The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
==Connectedness==<br />
This topic has many applications in the real world that are very interesting. For example, an application for Lenz's Law is to cause rotation to create energy. In an industry setting, Lenz's Law can be applied to electric generators or electric motors. When a current is induced in a generator, the direction of the induced current will flow in opposition of the magnetic field that created it, causing rotation of the generator. <br />
[[File:use235.jpg]]<br />
<br />
Another real world application of Lenz's Law is in electromagnetic braking in vehicles. This process begins with electromagnets inducing eddy currents into the spinning rotor. Magnetic fields that oppose the initial change in magnetic flux are created from these eddy currents (Lenz's Law). This ultimately slows the rotor.<br />
<br />
[[File:engine.jpg]]<br />
<br />
Another example of Lenz's Law in the real world is in Induction stovetops. These cooktops heat up as a result of changing magnetic fields and eddy currents operating according to Lenz's Law.<br />
<br />
[[File:stovetop.jpg]]<br />
<br />
==History==<br />
<br />
Henrich Friefrich Emil Lenz (1804-1865), a Russian physicist of German origin was born in Dorpat, nowadays Tartu, Estonia. Henrich studied chemistry and physics at the University of Dorpat in 1820 after his secondary education. From 1823 to 1826, he traveled with the navigator, Otto von Kotzebue on his third expedition around the world. During this journey he studied climate conditions, and properties of seawater. After his travels, he worked at the University of St. Petersburg, Russia, where he later became the Dean of Mathematics and Physics from 1840 to 1863. In the year of 1831, he started studying electromagnetism, and soon after in 1835, what is known today as Lenz's Law was created. Lenz was also know for carefully checking his work, testing any variable that might effect his results. Lenz died on February 10, 1865, just two days before his 61st birthday, after suffering a stroke, while in Rome.<br />
<br />
== See also ==<br />
<br />
Since Lenz's Law and Farady's Law go hand in hand, Faraday's Law would be great supplemental information to read about. Newton's Third Law would also be a topic to read on for further understanding why Lenz's Law exists. <br />
<br />
===Further reading===<br />
<br />
Faraday's Law<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html]<br />
Conservation Laws<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html]<br />
<br />
==References==<br />
<br />
https://nationalmaglab.org/education/magnet-academy/history-of-electricity-magnetism/pioneers/heinrich-friedrich-emil-lenz<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html<br />
http://regentsprep.org/regents/physics/phys08/clenslaw/<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html<br />
http://farside.ph.utexas.edu/teaching/302l/lectures/node85.html<br />
http://www.electrical4u.com/lenz-law-of-electromagnetic-induction/<br />
<br />
[[Category:Which Category did you place this in?]]</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=Lenz%27s_Law&diff=31664Lenz's Law2018-04-18T22:02:32Z<p>Nromer3: /* Middling */</p>
<hr />
<div>'''Edited by Nicole Romer (Spring 2018)'''<br />
<br />
'''Claimed by Jenny Zang (Fall 2016)'''<br />
<br />
'''Edited by Halle Bryan (Fall 2016)'''<br />
<br />
Formulated in 1834, Lenz's Law helps determine the direction of current and the field is creates. When an induced current is generated by a change in magnetic flux, as stated by Farady's Law, the induced current will flow creating its own magnetic field that opposes the magnetic field that created it. Lenz's Law and Faraday's Law of Induction are highly connected, with the negative sign in Faraday's Law showing Lenz's Law. The current direction is important in the upholding of the conservation of energy. Lenz's Law is connected to this conservation and therefore Newton's Third Law as well. <br />
<br />
==The Main Idea==<br />
<br />
Lenz's Law makes sure that Faraday's Law follows the conservation of energy as stated by Newton's Third Law. According to Faraday's Law, any change in the magnetic field will cause an induced current (emf). Lenz's Law accounts for the direction of the induced current. The change can be caused by the strength of the magnetic field, the direction of the magnetic field, the position of a circuit, the shape of a circuit, or the orientation of a circuit. The induced magnetic field inside a loop of wires is created to keep the magnetic flux in the loop constant. Any change in magnetic flux results in an equal and opposite change in the loop which is why we use negative dB/dt. This graphic displays a basic understanding of how Lenz's Law could function in one example where the existing magnetic field is increasing:<br />
<br />
[[File:sc235.jpg]]<br />
<br />
===A Mathematical Model===<br />
<br />
Lenz's Law is mathematically modeled as part of Faraday's Law. The negative sign in the equation represents the opposing induced field. <br />
<math>\epsilon = -{\frac{d\phi}{dt}} </math> where '''<math>\epsilon</math>''' is the emf of the system and '''<math>d\phi</math>''' is the change in the magnetic field.<br />
<br />
===A Computational Model===<br />
<br />
https://www.youtube.com/watch?v=xxZenoBs2Pg This links to a video by Khan Academy that explains how Lenz's Law works through an example.<br />
<br />
https://www.youtube.com/watch?v=Vs3afgStVy4 This links to a video by Grand Illusions that displays Lenz's Law using a magnetic falling down a tube.<br />
<br />
==Examples==<br />
'''Example Using Right Hand Rule'''<br />
<br />
Use the right hand rule to find the non-coulombic electric field in the given situations.<br />
[[File:Non-Coulobmic_Fields.gif]]<br />
<br />
'''Solution'''<br />
<br />
To use the right hand rule: place your thumb in the direction of the <math> -dB </math>, then curl your fingers. The direction in which your fingers curl is the direction of the non-coulombic electric field. The non-coulombic field is represented by the pink arrows.<br />
<br />
===Simple===<br />
<br />
A solenoid has current <math> I_1 </math> flowing around it increasing from 0 to 40A. A plain loop of wire is placed around the solenoid, perpendicular to the axis of the solenoid. An emf is produced, therefore producing an <math> I_2 </math>. Are <math> I_1 </math> and <math> I_2 </math> flowing in the same direction or opposite?<br />
<br />
'''Solution'''<br />
The original current <math> I_1 </math> produced a magnetic field. In order to maintain the conservation of energy and Newton's Third Law, the magnetic field produced by <math> I_2 </math> must oppose this field. This is in accordance with Lenz's Law. Therefore, <math> I_2 </math> must oppose <math> I_1 </math> in direction.<br />
<br />
<br />
===Middling===<br />
<br />
An magnet is moving through a copper tube (velocity drawn). Find the direction of -dB/dt and the direction of the induced current. Remember to use the right hand rule.<br />
<br />
[[File:LenzLaw.jpg]]<br />
<br />
'''Solution'''<br />
A)-y, clockwise B)+y, counterclockwise C)+y, counterclockwise D)-y, clockwise<br />
<br />
<br />
The magnetic field in this graphic is decreasing at a rate of 5.0mT/s. What is the direction of the current in the circle of wire?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
<br />
'''Solution'''<br />
The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. This is in accordance with Lenz's Law. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
===Difficult===<br />
The magnetic field is decreasing at a rate of 5.0mT/s. The radius of the loop of wire is 5.0m, and the resistance is 5 ohms. What is the magnitude and direction of the current?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
'''Solution'''<br />
<br />
To find the magnitude of the current we must first use the formula <math>\epsilon = -{\frac{d\phi}{dt}} </math> to find the <math>\epsilon</math> representing the emf of the system. We know, more specifically, that <math>\epsilon = -NAcos\theta{\frac{d\phi}{dt}} </math>. Therefore, <math>\epsilon = -1*5.0^2*\pi*1*-5*10^{-3} </math> which resolves to <math>\epsilon = .392699</math>. From there, to find the current we know that <math>I = {\frac{\epsilon}{R}}</math>. Plugging in the values we know we find, <math>I = {\frac{.392699}{5.0}} = .07854A</math>. That is the magnitude of the current. To find the direction we must use Lenz's Law. The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
==Connectedness==<br />
This topic has many applications in the real world that are very interesting. For example, an application for Lenz's Law is to cause rotation to create energy. In an industry setting, Lenz's Law can be applied to electric generators or electric motors. When a current is induced in a generator, the direction of the induced current will flow in opposition of the magnetic field that created it, causing rotation of the generator. <br />
[[File:use235.jpg]]<br />
<br />
Another real world application of Lenz's Law is in electromagnetic braking in vehicles. This process begins with electromagnets inducing eddy currents into the spinning rotor. Magnetic fields that oppose the initial change in magnetic flux are created from these eddy currents (Lenz's Law). This ultimately slows the rotor.<br />
<br />
[[File:engine.jpg]]<br />
<br />
Another example of Lenz's Law in the real world is in Induction stovetops. These cooktops heat up as a result of changing magnetic fields and eddy currents operating according to Lenz's Law.<br />
<br />
[[File:stovetop.jpg]]<br />
<br />
==History==<br />
<br />
Henrich Friefrich Emil Lenz (1804-1865), a Russian physicist of German origin was born in Dorpat, nowadays Tartu, Estonia. Henrich studied chemistry and physics at the University of Dorpat in 1820 after his secondary education. From 1823 to 1826, he traveled with the navigator, Otto von Kotzebue on his third expedition around the world. During this journey he studied climate conditions, and properties of seawater. After his travels, he worked at the University of St. Petersburg, Russia, where he later became the Dean of Mathematics and Physics from 1840 to 1863. In the year of 1831, he started studying electromagnetism, and soon after in 1835, what is known today as Lenz's Law was created. Lenz was also know for carefully checking his work, testing any variable that might effect his results. Lenz died on February 10, 1865, just two days before his 61st birthday, after suffering a stroke, while in Rome.<br />
<br />
== See also ==<br />
<br />
Since Lenz's Law and Farady's Law go hand in hand, Faraday's Law would be great supplemental information to read about. Newton's Third Law would also be a topic to read on for further understanding why Lenz's Law exists. <br />
<br />
===Further reading===<br />
<br />
Faraday's Law<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html]<br />
Conservation Laws<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html]<br />
<br />
==References==<br />
<br />
https://nationalmaglab.org/education/magnet-academy/history-of-electricity-magnetism/pioneers/heinrich-friedrich-emil-lenz<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html<br />
http://regentsprep.org/regents/physics/phys08/clenslaw/<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html<br />
http://farside.ph.utexas.edu/teaching/302l/lectures/node85.html<br />
http://www.electrical4u.com/lenz-law-of-electromagnetic-induction/<br />
<br />
[[Category:Which Category did you place this in?]]</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=Lenz%27s_Law&diff=31663Lenz's Law2018-04-18T22:02:09Z<p>Nromer3: </p>
<hr />
<div>'''Edited by Nicole Romer (Spring 2018)'''<br />
<br />
'''Claimed by Jenny Zang (Fall 2016)'''<br />
<br />
'''Edited by Halle Bryan (Fall 2016)'''<br />
<br />
Formulated in 1834, Lenz's Law helps determine the direction of current and the field is creates. When an induced current is generated by a change in magnetic flux, as stated by Farady's Law, the induced current will flow creating its own magnetic field that opposes the magnetic field that created it. Lenz's Law and Faraday's Law of Induction are highly connected, with the negative sign in Faraday's Law showing Lenz's Law. The current direction is important in the upholding of the conservation of energy. Lenz's Law is connected to this conservation and therefore Newton's Third Law as well. <br />
<br />
==The Main Idea==<br />
<br />
Lenz's Law makes sure that Faraday's Law follows the conservation of energy as stated by Newton's Third Law. According to Faraday's Law, any change in the magnetic field will cause an induced current (emf). Lenz's Law accounts for the direction of the induced current. The change can be caused by the strength of the magnetic field, the direction of the magnetic field, the position of a circuit, the shape of a circuit, or the orientation of a circuit. The induced magnetic field inside a loop of wires is created to keep the magnetic flux in the loop constant. Any change in magnetic flux results in an equal and opposite change in the loop which is why we use negative dB/dt. This graphic displays a basic understanding of how Lenz's Law could function in one example where the existing magnetic field is increasing:<br />
<br />
[[File:sc235.jpg]]<br />
<br />
===A Mathematical Model===<br />
<br />
Lenz's Law is mathematically modeled as part of Faraday's Law. The negative sign in the equation represents the opposing induced field. <br />
<math>\epsilon = -{\frac{d\phi}{dt}} </math> where '''<math>\epsilon</math>''' is the emf of the system and '''<math>d\phi</math>''' is the change in the magnetic field.<br />
<br />
===A Computational Model===<br />
<br />
https://www.youtube.com/watch?v=xxZenoBs2Pg This links to a video by Khan Academy that explains how Lenz's Law works through an example.<br />
<br />
https://www.youtube.com/watch?v=Vs3afgStVy4 This links to a video by Grand Illusions that displays Lenz's Law using a magnetic falling down a tube.<br />
<br />
==Examples==<br />
'''Example Using Right Hand Rule'''<br />
<br />
Use the right hand rule to find the non-coulombic electric field in the given situations.<br />
[[File:Non-Coulobmic_Fields.gif]]<br />
<br />
'''Solution'''<br />
<br />
To use the right hand rule: place your thumb in the direction of the <math> -dB </math>, then curl your fingers. The direction in which your fingers curl is the direction of the non-coulombic electric field. The non-coulombic field is represented by the pink arrows.<br />
<br />
===Simple===<br />
<br />
A solenoid has current <math> I_1 </math> flowing around it increasing from 0 to 40A. A plain loop of wire is placed around the solenoid, perpendicular to the axis of the solenoid. An emf is produced, therefore producing an <math> I_2 </math>. Are <math> I_1 </math> and <math> I_2 </math> flowing in the same direction or opposite?<br />
<br />
'''Solution'''<br />
The original current <math> I_1 </math> produced a magnetic field. In order to maintain the conservation of energy and Newton's Third Law, the magnetic field produced by <math> I_2 </math> must oppose this field. This is in accordance with Lenz's Law. Therefore, <math> I_2 </math> must oppose <math> I_1 </math> in direction.<br />
<br />
<br />
===Middling===<br />
<br />
An magnet is moving through a copper tube (velocity drawn). Find the direction of -dB/dt and the direction of the induced current. Remember to use the right hand rule.<br />
[[File:LenzLaw.jpg]]<br />
<br />
'''Solution'''<br />
A)-y, clockwise B)+y, counterclockwise C)+y, counterclockwise D)-y, clockwise<br />
<br />
<br />
The magnetic field in this graphic is decreasing at a rate of 5.0mT/s. What is the direction of the current in the circle of wire?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
<br />
'''Solution'''<br />
The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. This is in accordance with Lenz's Law. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
===Difficult===<br />
The magnetic field is decreasing at a rate of 5.0mT/s. The radius of the loop of wire is 5.0m, and the resistance is 5 ohms. What is the magnitude and direction of the current?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
'''Solution'''<br />
<br />
To find the magnitude of the current we must first use the formula <math>\epsilon = -{\frac{d\phi}{dt}} </math> to find the <math>\epsilon</math> representing the emf of the system. We know, more specifically, that <math>\epsilon = -NAcos\theta{\frac{d\phi}{dt}} </math>. Therefore, <math>\epsilon = -1*5.0^2*\pi*1*-5*10^{-3} </math> which resolves to <math>\epsilon = .392699</math>. From there, to find the current we know that <math>I = {\frac{\epsilon}{R}}</math>. Plugging in the values we know we find, <math>I = {\frac{.392699}{5.0}} = .07854A</math>. That is the magnitude of the current. To find the direction we must use Lenz's Law. The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
==Connectedness==<br />
This topic has many applications in the real world that are very interesting. For example, an application for Lenz's Law is to cause rotation to create energy. In an industry setting, Lenz's Law can be applied to electric generators or electric motors. When a current is induced in a generator, the direction of the induced current will flow in opposition of the magnetic field that created it, causing rotation of the generator. <br />
[[File:use235.jpg]]<br />
<br />
Another real world application of Lenz's Law is in electromagnetic braking in vehicles. This process begins with electromagnets inducing eddy currents into the spinning rotor. Magnetic fields that oppose the initial change in magnetic flux are created from these eddy currents (Lenz's Law). This ultimately slows the rotor.<br />
<br />
[[File:engine.jpg]]<br />
<br />
Another example of Lenz's Law in the real world is in Induction stovetops. These cooktops heat up as a result of changing magnetic fields and eddy currents operating according to Lenz's Law.<br />
<br />
[[File:stovetop.jpg]]<br />
<br />
==History==<br />
<br />
Henrich Friefrich Emil Lenz (1804-1865), a Russian physicist of German origin was born in Dorpat, nowadays Tartu, Estonia. Henrich studied chemistry and physics at the University of Dorpat in 1820 after his secondary education. From 1823 to 1826, he traveled with the navigator, Otto von Kotzebue on his third expedition around the world. During this journey he studied climate conditions, and properties of seawater. After his travels, he worked at the University of St. Petersburg, Russia, where he later became the Dean of Mathematics and Physics from 1840 to 1863. In the year of 1831, he started studying electromagnetism, and soon after in 1835, what is known today as Lenz's Law was created. Lenz was also know for carefully checking his work, testing any variable that might effect his results. Lenz died on February 10, 1865, just two days before his 61st birthday, after suffering a stroke, while in Rome.<br />
<br />
== See also ==<br />
<br />
Since Lenz's Law and Farady's Law go hand in hand, Faraday's Law would be great supplemental information to read about. Newton's Third Law would also be a topic to read on for further understanding why Lenz's Law exists. <br />
<br />
===Further reading===<br />
<br />
Faraday's Law<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html]<br />
Conservation Laws<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html]<br />
<br />
==References==<br />
<br />
https://nationalmaglab.org/education/magnet-academy/history-of-electricity-magnetism/pioneers/heinrich-friedrich-emil-lenz<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html<br />
http://regentsprep.org/regents/physics/phys08/clenslaw/<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html<br />
http://farside.ph.utexas.edu/teaching/302l/lectures/node85.html<br />
http://www.electrical4u.com/lenz-law-of-electromagnetic-induction/<br />
<br />
[[Category:Which Category did you place this in?]]</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=Lenz%27s_Law&diff=31662Lenz's Law2018-04-18T22:01:47Z<p>Nromer3: Minor fix</p>
<hr />
<div>'''Claimed by Nicole Romer (Spring 2018)'''<br />
<br />
'''Claimed by Jenny Zang (Fall 2016)'''<br />
<br />
'''Edited by Halle Bryan (Fall 2016)'''<br />
<br />
Formulated in 1834, Lenz's Law helps determine the direction of current and the field is creates. When an induced current is generated by a change in magnetic flux, as stated by Farady's Law, the induced current will flow creating its own magnetic field that opposes the magnetic field that created it. Lenz's Law and Faraday's Law of Induction are highly connected, with the negative sign in Faraday's Law showing Lenz's Law. The current direction is important in the upholding of the conservation of energy. Lenz's Law is connected to this conservation and therefore Newton's Third Law as well. <br />
<br />
==The Main Idea==<br />
<br />
Lenz's Law makes sure that Faraday's Law follows the conservation of energy as stated by Newton's Third Law. According to Faraday's Law, any change in the magnetic field will cause an induced current (emf). Lenz's Law accounts for the direction of the induced current. The change can be caused by the strength of the magnetic field, the direction of the magnetic field, the position of a circuit, the shape of a circuit, or the orientation of a circuit. The induced magnetic field inside a loop of wires is created to keep the magnetic flux in the loop constant. Any change in magnetic flux results in an equal and opposite change in the loop which is why we use negative dB/dt. This graphic displays a basic understanding of how Lenz's Law could function in one example where the existing magnetic field is increasing:<br />
<br />
[[File:sc235.jpg]]<br />
<br />
===A Mathematical Model===<br />
<br />
Lenz's Law is mathematically modeled as part of Faraday's Law. The negative sign in the equation represents the opposing induced field. <br />
<math>\epsilon = -{\frac{d\phi}{dt}} </math> where '''<math>\epsilon</math>''' is the emf of the system and '''<math>d\phi</math>''' is the change in the magnetic field.<br />
<br />
===A Computational Model===<br />
<br />
https://www.youtube.com/watch?v=xxZenoBs2Pg This links to a video by Khan Academy that explains how Lenz's Law works through an example.<br />
<br />
https://www.youtube.com/watch?v=Vs3afgStVy4 This links to a video by Grand Illusions that displays Lenz's Law using a magnetic falling down a tube.<br />
<br />
==Examples==<br />
'''Example Using Right Hand Rule'''<br />
<br />
Use the right hand rule to find the non-coulombic electric field in the given situations.<br />
[[File:Non-Coulobmic_Fields.gif]]<br />
<br />
'''Solution'''<br />
<br />
To use the right hand rule: place your thumb in the direction of the <math> -dB </math>, then curl your fingers. The direction in which your fingers curl is the direction of the non-coulombic electric field. The non-coulombic field is represented by the pink arrows.<br />
<br />
===Simple===<br />
<br />
A solenoid has current <math> I_1 </math> flowing around it increasing from 0 to 40A. A plain loop of wire is placed around the solenoid, perpendicular to the axis of the solenoid. An emf is produced, therefore producing an <math> I_2 </math>. Are <math> I_1 </math> and <math> I_2 </math> flowing in the same direction or opposite?<br />
<br />
'''Solution'''<br />
The original current <math> I_1 </math> produced a magnetic field. In order to maintain the conservation of energy and Newton's Third Law, the magnetic field produced by <math> I_2 </math> must oppose this field. This is in accordance with Lenz's Law. Therefore, <math> I_2 </math> must oppose <math> I_1 </math> in direction.<br />
<br />
<br />
===Middling===<br />
<br />
An magnet is moving through a copper tube (velocity drawn). Find the direction of -dB/dt and the direction of the induced current. Remember to use the right hand rule.<br />
[[File:LenzLaw.jpg]]<br />
<br />
'''Solution'''<br />
A)-y, clockwise B)+y, counterclockwise C)+y, counterclockwise D)-y, clockwise<br />
<br />
<br />
The magnetic field in this graphic is decreasing at a rate of 5.0mT/s. What is the direction of the current in the circle of wire?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
<br />
'''Solution'''<br />
The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. This is in accordance with Lenz's Law. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
===Difficult===<br />
The magnetic field is decreasing at a rate of 5.0mT/s. The radius of the loop of wire is 5.0m, and the resistance is 5 ohms. What is the magnitude and direction of the current?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
'''Solution'''<br />
<br />
To find the magnitude of the current we must first use the formula <math>\epsilon = -{\frac{d\phi}{dt}} </math> to find the <math>\epsilon</math> representing the emf of the system. We know, more specifically, that <math>\epsilon = -NAcos\theta{\frac{d\phi}{dt}} </math>. Therefore, <math>\epsilon = -1*5.0^2*\pi*1*-5*10^{-3} </math> which resolves to <math>\epsilon = .392699</math>. From there, to find the current we know that <math>I = {\frac{\epsilon}{R}}</math>. Plugging in the values we know we find, <math>I = {\frac{.392699}{5.0}} = .07854A</math>. That is the magnitude of the current. To find the direction we must use Lenz's Law. The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
==Connectedness==<br />
This topic has many applications in the real world that are very interesting. For example, an application for Lenz's Law is to cause rotation to create energy. In an industry setting, Lenz's Law can be applied to electric generators or electric motors. When a current is induced in a generator, the direction of the induced current will flow in opposition of the magnetic field that created it, causing rotation of the generator. <br />
[[File:use235.jpg]]<br />
<br />
Another real world application of Lenz's Law is in electromagnetic braking in vehicles. This process begins with electromagnets inducing eddy currents into the spinning rotor. Magnetic fields that oppose the initial change in magnetic flux are created from these eddy currents (Lenz's Law). This ultimately slows the rotor.<br />
<br />
[[File:engine.jpg]]<br />
<br />
Another example of Lenz's Law in the real world is in Induction stovetops. These cooktops heat up as a result of changing magnetic fields and eddy currents operating according to Lenz's Law.<br />
<br />
[[File:stovetop.jpg]]<br />
<br />
==History==<br />
<br />
Henrich Friefrich Emil Lenz (1804-1865), a Russian physicist of German origin was born in Dorpat, nowadays Tartu, Estonia. Henrich studied chemistry and physics at the University of Dorpat in 1820 after his secondary education. From 1823 to 1826, he traveled with the navigator, Otto von Kotzebue on his third expedition around the world. During this journey he studied climate conditions, and properties of seawater. After his travels, he worked at the University of St. Petersburg, Russia, where he later became the Dean of Mathematics and Physics from 1840 to 1863. In the year of 1831, he started studying electromagnetism, and soon after in 1835, what is known today as Lenz's Law was created. Lenz was also know for carefully checking his work, testing any variable that might effect his results. Lenz died on February 10, 1865, just two days before his 61st birthday, after suffering a stroke, while in Rome.<br />
<br />
== See also ==<br />
<br />
Since Lenz's Law and Farady's Law go hand in hand, Faraday's Law would be great supplemental information to read about. Newton's Third Law would also be a topic to read on for further understanding why Lenz's Law exists. <br />
<br />
===Further reading===<br />
<br />
Faraday's Law<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html]<br />
Conservation Laws<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html]<br />
<br />
==References==<br />
<br />
https://nationalmaglab.org/education/magnet-academy/history-of-electricity-magnetism/pioneers/heinrich-friedrich-emil-lenz<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html<br />
http://regentsprep.org/regents/physics/phys08/clenslaw/<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html<br />
http://farside.ph.utexas.edu/teaching/302l/lectures/node85.html<br />
http://www.electrical4u.com/lenz-law-of-electromagnetic-induction/<br />
<br />
[[Category:Which Category did you place this in?]]</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=File:LenzLaw.jpg&diff=31659File:LenzLaw.jpg2018-04-18T21:59:55Z<p>Nromer3: Nromer3 uploaded a new version of &quot;File:LenzLaw.jpg&quot;</p>
<hr />
<div>Example problem</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=File:LenzLaw.jpg&diff=31658File:LenzLaw.jpg2018-04-18T21:57:59Z<p>Nromer3: Nromer3 uploaded a new version of &quot;File:LenzLaw.jpg&quot;</p>
<hr />
<div>Example problem</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=Lenz%27s_Law&diff=31657Lenz's Law2018-04-18T21:56:36Z<p>Nromer3: Fixing minor errors</p>
<hr />
<div>'''Claimed by Nicole Romer (Spring 2018)'''<br />
<br />
'''Claimed by Jenny Zang (Fall 2016)'''<br />
<br />
'''Edited by Halle Bryan (Fall 2016)'''<br />
<br />
Formulated in 1834, Lenz's Law helps determine the direction of current and the field is creates. When an induced current is generated by a change in magnetic flux, as stated by Farady's Law, the induced current will flow creating its own magnetic field that opposes the magnetic field that created it. Lenz's Law and Faraday's Law of Induction are highly connected, with the negative sign in Faraday's Law showing Lenz's Law. The current direction is important in the upholding of the conservation of energy. Lenz's Law is connected to this conservation and therefore Newton's Third Law as well. <br />
<br />
==The Main Idea==<br />
<br />
Lenz's Law makes sure that Faraday's Law follows the conservation of energy as stated by Newton's Third Law. According to Faraday's Law, any change in the magnetic field will cause an induced current (emf). Lenz's Law accounts for the direction of the induced current. The change can be caused by the strength of the magnetic field, the direction of the magnetic field, the position of a circuit, the shape of a circuit, or the orientation of a circuit. The induced magnetic field inside a loop of wires is created to keep the magnetic flux in the loop constant. Any change in magnetic flux results in an equal and opposite change in the loop which is why we use negative dB/dt. This graphic displays a basic understanding of how Lenz's Law could function in one example where the existing magnetic field is increasing:<br />
<br />
[[File:sc235.jpg]]<br />
<br />
===A Mathematical Model===<br />
<br />
Lenz's Law is mathematically modeled as part of Faraday's Law. The negative sign in the equation represents the opposing induced field. <br />
<math>\epsilon = -{\frac{d\phi}{dt}} </math> where '''<math>\epsilon</math>''' is the emf of the system and '''<math>d\phi</math>''' is the change in the magnetic field.<br />
<br />
===A Computational Model===<br />
<br />
https://www.youtube.com/watch?v=xxZenoBs2Pg This links to a video by Khan Academy that explains how Lenz's Law works through an example.<br />
<br />
https://www.youtube.com/watch?v=Vs3afgStVy4 This links to a video by Grand Illusions that displays Lenz's Law using a magnetic falling down a tube.<br />
<br />
==Examples==<br />
'''Example Using Right Hand Rule'''<br />
<br />
Use the right hand rule to find the non-coulombic electric field in the given situations.<br />
[[File:Non-Coulobmic_Fields.gif]]<br />
<br />
'''Solution'''<br />
<br />
To use the right hand rule: place your thumb in the direction of the <math> -dB </math>, then curl your fingers. The direction in which your fingers curl is the direction of the non-coulombic electric field. The non-coulombic field is represented by the pink arrows.<br />
<br />
===Simple===<br />
<br />
A solenoid has current <math> I_1 </math> flowing around it increasing from 0 to 40A. A plain loop of wire is placed around the solenoid, perpendicular to the axis of the solenoid. An emf is produced, therefore producing an <math> I_2 </math>. Are <math> I_1 </math> and <math> I_2 </math> flowing in the same direction or opposite?<br />
<br />
'''Solution'''<br />
The original current <math> I_1 </math> produced a magnetic field. In order to maintain the conservation of energy and Newton's Third Law, the magnetic field produced by <math> I_2 </math> must oppose this field. This is in accordance with Lenz's Law. Therefore, <math> I_2 </math> must oppose <math> I_1 </math> in direction.<br />
<br />
<br />
===Middling===<br />
<br />
An magnet is moving through a copper tube (velocity drawn). Find the direction of -dB/dt and the direction of the induced current. Remember to use the right hand rule.<br />
[[File:LenzLaw.jpg]]<br />
<br />
'''Solution'''<br />
A)-y, clockwise B)+y, counterclockwise C)+y, counterclockwise D)-y, clockwise<br />
<br />
<br />
The magnetic field in this graphic is decreasing at a rate of 5.0mT/s. What is the direction of the current in the circle of wire?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
<br />
'''Solution'''<br />
The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. This is in accordance with Lenz's Law. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
===Difficult===<br />
The magnetic field is decreasing at a rate of 5.0mT/s. The radius of the loop of wire is 5.0m, and the resistance is 5 ohms. What is the magnitude and direction of the current?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
'''Solution'''<br />
<br />
To find the magnitude of the current we must first use the formula <math>\epsilon = -{\frac{d\phi}{dt}} </math> to find the <math>\epsilon</math> representing the emf of the system. We know, more specifically, that <math>\epsilon = -NAcos\theta{\frac{d\phi}{dt}} </math>. Therefore, <math>\epsilon = -1*5.0^2*\pi*1*-5*10^{-3} </math> which resolves to <math>\epsilon = .392699</math>. From there, to find the current we know that <math>I = {\frac{\epsilon}{R}}</math>. Plugging in the values we know we find, <math>I = {\frac{.392699}{5.0}} = .07854A</math>. That is the magnitude of the current. To find the direction we must use Lenz's Law. The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
==Connectedness==<br />
This topic has many applications in the real world that are very interesting. For example, an application for Lenz's Law is to cause rotation to create energy. In an industry setting, Lenz's Law can be applied to electric generators or electric motors. When a current is induced in a generator, the direction of the induced current will flow in opposition of the magnetic field that created it, causing rotation of the generator. <br />
[[File:use235.jpg]]<br />
<br />
Another real world application of Lenz's Law is in electromagnetic braking in vehicles. This process begins with electromagnets inducing eddy currents into the spinning rotor. Magnetic fields that oppose the initial change in magnetic flux are created from these eddy currents (Lenz's Law). This ultimately slows the rotor.<br />
<br />
[[File:engine.jpg]]<br />
<br />
Another example of Lenz's Law in the real world is in Induction stovetops. These cooktops heat up as a result of changing magnetic fields and eddy currents operating according to Lenz's Law.<br />
<br />
[[File:stovetop.jpg]]<br />
<br />
==History==<br />
<br />
Henrich Friefrich Emil Lenz (1804-1865), a Russian physicist of German origin was born in Dorpat, nowadays Tartu, Estonia. Henrich studied chemistry and physics at the University of Dorpat in 1820 after his secondary education. From 1823 to 1826, he traveled with the navigator, Otto von Kotzebue on his third expedition around the world. During this journey he studied climate conditions, and properties of seawater. After his travels, he worked at the University of St. Petersburg, Russia, where he later became the Dean of Mathematics and Physics from 1840 to 1863. In the year of 1831, he started studying electromagnetism, and soon after in 1835, what is known today as Lenz's Law was created. Lenz died on February 10, 1865, just two days before his 61st birthday, after suffering a stroke, while in Rome.<br />
<br />
== See also ==<br />
<br />
Since Lenz's Law and Farady's Law go hand in hand, Faraday's Law would be great supplemental information to read about. Newton's Third Law would also be a topic to read on for further understanding why Lenz's Law exists. <br />
<br />
===Further reading===<br />
<br />
Faraday's Law<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html]<br />
Conservation Laws<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html]<br />
<br />
==References==<br />
<br />
https://nationalmaglab.org/education/magnet-academy/history-of-electricity-magnetism/pioneers/heinrich-friedrich-emil-lenz<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html<br />
http://regentsprep.org/regents/physics/phys08/clenslaw/<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html<br />
http://farside.ph.utexas.edu/teaching/302l/lectures/node85.html<br />
http://www.electrical4u.com/lenz-law-of-electromagnetic-induction/<br />
<br />
[[Category:Which Category did you place this in?]]</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=File:LenzLaw.jpg&diff=31655File:LenzLaw.jpg2018-04-18T21:55:46Z<p>Nromer3: Example problem</p>
<hr />
<div>Example problem</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=Lenz%27s_Law&diff=31652Lenz's Law2018-04-18T21:50:40Z<p>Nromer3: Fixed a few small errors and added another example</p>
<hr />
<div>'''Claimed by Nicole Romer (Spring 2018)'''<br />
<br />
'''Claimed by Jenny Zang (Fall 2016)'''<br />
<br />
'''Edited by Halle Bryan (Fall 2016)'''<br />
<br />
Formulated in 1834, Lenz's Law helps determine the direction of current and the field is creates. When an induced current is generated by a change in magnetic flux, as stated by Farady's Law, the induced current will flow creating its own magnetic field that opposes the magnetic field that created it. Lenz's Law and Faraday's Law of Induction are highly connected, with the negative sign in Faraday's Law showing Lenz's Law. The current direction is important in the upholding of the conservation of energy. Lenz's Law is connected to this conservation and therefore Newton's Third Law as well. <br />
<br />
==The Main Idea==<br />
<br />
Lenz's Law makes sure that Faraday's Law follows the conservation of energy as stated by Newton's Third Law. According to Faraday's Law, any change in the magnetic field will cause an induced current (emf). Lenz's Law accounts for the direction of the induced current. The change can be caused by the strength of the magnetic field, the direction of the magnetic field, the position of a circuit, the shape of a circuit, or the orientation of a circuit. The induced magnetic field inside a loop of wires is created to keep the magnetic flux in the loop constant. Any change in magnetic flux results in an equal and opposite change in the loop which is why we use negative dB/dt. This graphic displays a basic understanding of how Lenz's Law could function in one example where the existing magnetic field is increasing:<br />
<br />
[[File:sc235.jpg]]<br />
<br />
===A Mathematical Model===<br />
<br />
Lenz's Law is mathematically modeled as part of Faraday's Law. The negative sign in the equation represents the opposing induced field. <br />
<math>\epsilon = -{\frac{d\phi}{dt}} </math> where '''<math>\epsilon</math>''' is the emf of the system and '''<math>d\phi</math>''' is the change in the magnetic field.<br />
<br />
===A Computational Model===<br />
<br />
https://www.youtube.com/watch?v=xxZenoBs2Pg This links to a video by Khan Academy that explains how Lenz's Law works through an example.<br />
<br />
https://www.youtube.com/watch?v=Vs3afgStVy4 This links to a video by Grand Illusions that displays Lenz's Law using a magnetic falling down a tube.<br />
<br />
==Examples==<br />
'''Example Using Right Hand Rule'''<br />
<br />
Use the right hand rule to find the non-coulombic electric field in the given situations.<br />
[[File:Non-Coulobmic_Fields.gif]]<br />
<br />
'''Solution'''<br />
<br />
To use the right hand rule: place your thumb in the direction of the <math> -dB </math>, then curl your fingers. The direction in which your fingers curl is the direction of the non-coulombic electric field. The non-coulombic field is represented by the pink arrows.<br />
<br />
===Simple===<br />
<br />
A solenoid has current <math> I_1 </math> flowing around it increasing from 0 to 40A. A plain loop of wire is placed around the solenoid, perpendicular to the axis of the solenoid. An emf is produced, therefore producing an <math> I_2 </math>. Are <math> I_1 </math> and <math> I_2 </math> flowing in the same direction or opposite?<br />
<br />
'''Solution'''<br />
The original current <math> I_1 </math> produced a magnetic field. In order to maintain the conservation of energy and Newton's Third Law, the magnetic field produced by <math> I_2 </math> must oppose this field. This is in accordance with Lenz's Law. Therefore, <math> I_2 </math> must oppose <math> I_1 </math> in direction.<br />
<br />
<br />
===Middling===<br />
<br />
An magnet is moving through a copper tube (velocity drawn). Find the direction of -dB/dt and the direction of the induced current. Remember to use the right hand rule.<br />
[[File:lenzLaw.jpg]]<br />
<br />
'''Solution'''<br />
A)-y, clockwise B)+y, counterclockwise C)+y, counterclockwise D)-y, clockwise<br />
<br />
The magnetic field in this graphic is decreasing at a rate of 5.0mT/s. What is the direction of the current in the circle of wire?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
<br />
'''Solution'''<br />
The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. This is in accordance with Lenz's Law. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
===Difficult===<br />
The magnetic field is decreasing at a rate of 5.0mT/s. The radius of the loop of wire is 5.0m, and the resistance is 5 ohms. What is the magnitude and direction of the current?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
'''Solution'''<br />
<br />
To find the magnitude of the current we must first use the formula <math>\epsilon = -{\frac{d\phi}{dt}} </math> to find the <math>\epsilon</math> representing the emf of the system. We know, more specifically, that <math>\epsilon = -NAcos\theta{\frac{d\phi}{dt}} </math>. Therefore, <math>\epsilon = -1*5.0^2*\pi*1*-5*10^{-3} </math> which resolves to <math>\epsilon = .392699</math>. From there, to find the current we know that <math>I = {\frac{\epsilon}{R}}</math>. Plugging in the values we know we find, <math>I = {\frac{.392699}{5.0}} = .07854A</math>. That is the magnitude of the current. To find the direction we must use Lenz's Law. The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
==Connectedness==<br />
This topic has many applications in the real world that are very interesting. For example, an application for Lenz's Law is to cause rotation to create energy. In an industry setting, Lenz's Law can be applied to electric generators or electric motors. When a current is induced in a generator, the direction of the induced current will flow in opposition of the magnetic field that created it, causing rotation of the generator. <br />
[[File:use235.jpg]]<br />
<br />
Another real world application of Lenz's Law is in electromagnetic braking in vehicles. This process begins with electromagnets inducing eddy currents into the spinning rotor. Magnetic fields that oppose the initial change in magnetic flux are created from these eddy currents (Lenz's Law). This ultimately slows the rotor.<br />
<br />
[[File:engine.jpg]]<br />
<br />
Another example of Lenz's Law in the real world is in Induction stovetops. These cooktops heat up as a result of changing magnetic fields and eddy currents operating according to Lenz's Law.<br />
<br />
[[File:stovetop.jpg]]<br />
<br />
==History==<br />
<br />
Henrich Friefrich Emil Lenz (1804-1865), a Russian physicist of German origin was born in Dorpat, nowadays Tartu, Estonia. Henrich studied chemistry and physics at the University of Dorpat in 1820 after his secondary education. From 1823 to 1826, he traveled with the navigator, Otto von Kotzebue on his third expedition around the world. During this journey he studied climate conditions, and properties of seawater. After his travels, he worked at the University of St. Petersburg, Russia, where he later became the Dean of Mathematics and Physics from 1840 to 1863. In the year of 1831, he started studying electromagnetism, and soon after in 1835, what is known today as Lenz's Law was created. Lenz died on February 10, 1865, just two days before his 61st birthday, after suffering a stroke, while in Rome.<br />
<br />
== See also ==<br />
<br />
Since Lenz's Law and Farady's Law go hand in hand, Faraday's Law would be great supplemental information to read about. Newton's Third Law would also be a topic to read on for further understanding why Lenz's Law exists. <br />
<br />
===Further reading===<br />
<br />
Faraday's Law<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html]<br />
Conservation Laws<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html]<br />
<br />
==References==<br />
<br />
https://nationalmaglab.org/education/magnet-academy/history-of-electricity-magnetism/pioneers/heinrich-friedrich-emil-lenz<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html<br />
http://regentsprep.org/regents/physics/phys08/clenslaw/<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html<br />
http://farside.ph.utexas.edu/teaching/302l/lectures/node85.html<br />
http://www.electrical4u.com/lenz-law-of-electromagnetic-induction/<br />
<br />
[[Category:Which Category did you place this in?]]</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=Lenz%27s_Law&diff=31455Lenz's Law2018-04-18T16:55:41Z<p>Nromer3: </p>
<hr />
<div>'''Claimed by Nicole Romer (Spring 2018)'''<br />
<br />
'''Claimed by Jenny Zang (Fall 2016)'''<br />
<br />
'''Edited by Halle Bryan (Fall 2016)'''<br />
<br />
Formulated in 1834, Lenz's Law helps determine the direction of current and the field is creates. When an induced current is generated by a change in magnetic flux, as stated by Farady's Law, the induced current will flow creating its own magnetic field that opposes the magnetic field that created it. Lenz's Law and Faraday's Law of Induction are highly connected, with the negative sign in Faraday's Law showing Lenz's Law. The current direction is important in the upholding of the conservation of energy. Lenz's Law is connected to this conservation and therefore Newton's Third Law as well. <br />
<br />
==The Main Idea==<br />
<br />
Lenz's Law makes sure that Faraday's Law follows the conservation of energy as stated by Newton's Third Law. According to Faraday's Law, any change a the magnetic field will cause an induced current (emf). Lenz's Law accounts for the direction of the induced current. The change can be caused by the strength of the magnetic field, the direction of the magnetic field, the position of a circuit, the shape of a circuit, or the orientation of a circuit. The induced magnetic field inside a loop of wires is created to keep the magnetic flux in the loop constant. This graphic displays a basic understanding of how Lenz's Law could function in one example where the existing magnetic field is increasing:<br />
<br />
[[File:sc235.jpg]]<br />
<br />
===A Mathematical Model===<br />
<br />
Lenz's Law is mathematically modeled as part of Faraday's Law. The negative sign in the equation represents the opposing induced field. <br />
<math>\epsilon = -{\frac{d\phi}{dt}} </math> where '''<math>\epsilon</math>''' is the emf of the system and '''<math>d\phi</math>''' is the change in the magnetic field.<br />
<br />
===A Computational Model===<br />
<br />
https://www.youtube.com/watch?v=xxZenoBs2Pg This links to a video by Khan Academy that explains how Lenz's Law works through an example.<br />
<br />
https://www.youtube.com/watch?v=Vs3afgStVy4 This links to a video by Grand Illusions that displays Lenz's Law using a magnetic falling down a tube.<br />
<br />
==Examples==<br />
'''Example Using Right Hand Rule'''<br />
<br />
Use the right hand rule to find the non-coulombic electric field in the given situations.<br />
[[File:Non-Coulobmic_Fields.gif]]<br />
<br />
'''Solution'''<br />
<br />
To use the right hand rule: place your thumb in the direction of the <math> -dB </math>, then curl your fingers. The direction in which your fingers curl is the direction of the non-coulombic electric field. The non-coulombic field is represented by the pink arrows.<br />
<br />
===Simple===<br />
<br />
A solenoid has current <math> I_1 </math> flowing around it increasing from 0 to 40A. A plain loop of wire is placed around the solenoid, perpendicular to the axis of the solenoid. An emf is produced, therefore producing an <math> I_2 </math>. Are <math> I_1 </math> and <math> I_2 </math> flowing in the same direction or opposite?<br />
<br />
'''Solution'''<br />
The original current <math> I_1 </math> produced a magnetic field. In order to maintain the conservation of energy and Newton's Third Law, the magnetic field produced by <math> I_2 </math> must oppose this field. This is in accordance with Lenz's Law. Therefore, <math> I_2 </math> must oppose <math> I_1 </math> in direction.<br />
<br />
===Middling===<br />
The magnetic field in this graphic is decreasing at a rate of 5.0mT/s. What is the direction of the current in the circle of wire?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
<br />
'''Solution'''<br />
The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. This is in accordance with Lenz's Law. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
===Difficult===<br />
The magnetic field is decreasing at a rate of 5.0mT/s. The radius of the loop of wire is 5.0m, and the resistance is 5 ohms. What is the magnitude and direction of the current?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
'''Solution'''<br />
<br />
To find the magnitude of the current we must first use the formula <math>\epsilon = -{\frac{d\phi}{dt}} </math> to find the <math>\epsilon</math> representing the emf of the system. We know, more specifically, that <math>\epsilon = -NAcos\theta{\frac{d\phi}{dt}} </math>. Therefore, <math>\epsilon = -1*5.0^2*\pi*1*-5*10^{-3} </math> which resolves to <math>\epsilon = .392699</math>. From there, to find the current we know that <math>I = {\frac{\epsilon}{R}}</math>. Plugging in the values we know we find, <math>I = {\frac{.392699}{5.0}} = .07854A</math>. That is the magnitude of the current. To find the direction we must use Lenz's Law. The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
==Connectedness==<br />
This topic has many applications in the real world that are very interesting. For example, an application for Lenz's Law is to cause rotation to create energy. In an industry setting, Lenz's Law can be applied to electric generators or electric motors. When a current is induced in a generator, the direction of the induced current will flow in opposition of the magnetic field that created it, causing rotation of the generator. <br />
[[File:use235.jpg]]<br />
<br />
Another real world application of Lenz's Law is in electromagnetic braking in vehicles. This process begins with electromagnets inducing eddy currents into the spinning rotor. Magnetic fields that oppose the initial change in magnetic flux are created from these eddy currents (Lenz's Law). This ultimately slows the rotor.<br />
<br />
[[File:engine.jpg]]<br />
<br />
Another example of Lenz's Law in the real world is in Induction stovetops. These cooktops heat up as a result of changing magnetic fields and eddy currents operating according to Lenz's Law.<br />
<br />
[[File:stovetop.jpg]]<br />
<br />
==History==<br />
<br />
Henrich Friefrich Emil Lenz (1804-1865), a Russian physicist of German origin was born in Dorpat, nowadays Tartu, Estonia. Henrich studied chemistry and physics at the University of Dorpat in 1820 after his secondary education. From 1823 to 1826, he traveled with the navigator, Otto von Kotzebue on his third expedition around the world. During this journey he studied climate conditions, and properties of seawater. After his travels, he worked at the University of St. Petersburg, Russia, where he later became the Dean of Mathematics and Physics from 1840 to 1863. In the year of 1831, he started studying electromagnetism, and soon after in 1835, what is known today as Lenz's Law was created. Lenz died on February 10, 1865, just two days before his 61st birthday, after suffering a stroke, while in Rome.<br />
<br />
== See also ==<br />
<br />
Since Lenz's Law and Farady's Law go hand in hand, Faraday's Law would be great supplemental information to read about. Newton's Third Law would also be a topic to read on for further understanding why Lenz's Law exists. <br />
<br />
===Further reading===<br />
<br />
Faraday's Law<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html]<br />
Conservation Laws<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html]<br />
<br />
==References==<br />
<br />
https://nationalmaglab.org/education/magnet-academy/history-of-electricity-magnetism/pioneers/heinrich-friedrich-emil-lenz<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html<br />
http://regentsprep.org/regents/physics/phys08/clenslaw/<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html<br />
http://farside.ph.utexas.edu/teaching/302l/lectures/node85.html<br />
http://www.electrical4u.com/lenz-law-of-electromagnetic-induction/<br />
<br />
[[Category:Which Category did you place this in?]]</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=Lenz%27s_Law&diff=31454Lenz's Law2018-04-18T16:55:29Z<p>Nromer3: </p>
<hr />
<div>'''Claimed by Nicole Romer (Spring 2018)'''<br />
'''Claimed by Jenny Zang (Fall 2016)'''<br />
<br />
'''Edited by Halle Bryan (Fall 2016)'''<br />
<br />
Formulated in 1834, Lenz's Law helps determine the direction of current and the field is creates. When an induced current is generated by a change in magnetic flux, as stated by Farady's Law, the induced current will flow creating its own magnetic field that opposes the magnetic field that created it. Lenz's Law and Faraday's Law of Induction are highly connected, with the negative sign in Faraday's Law showing Lenz's Law. The current direction is important in the upholding of the conservation of energy. Lenz's Law is connected to this conservation and therefore Newton's Third Law as well. <br />
<br />
==The Main Idea==<br />
<br />
Lenz's Law makes sure that Faraday's Law follows the conservation of energy as stated by Newton's Third Law. According to Faraday's Law, any change a the magnetic field will cause an induced current (emf). Lenz's Law accounts for the direction of the induced current. The change can be caused by the strength of the magnetic field, the direction of the magnetic field, the position of a circuit, the shape of a circuit, or the orientation of a circuit. The induced magnetic field inside a loop of wires is created to keep the magnetic flux in the loop constant. This graphic displays a basic understanding of how Lenz's Law could function in one example where the existing magnetic field is increasing:<br />
<br />
[[File:sc235.jpg]]<br />
<br />
===A Mathematical Model===<br />
<br />
Lenz's Law is mathematically modeled as part of Faraday's Law. The negative sign in the equation represents the opposing induced field. <br />
<math>\epsilon = -{\frac{d\phi}{dt}} </math> where '''<math>\epsilon</math>''' is the emf of the system and '''<math>d\phi</math>''' is the change in the magnetic field.<br />
<br />
===A Computational Model===<br />
<br />
https://www.youtube.com/watch?v=xxZenoBs2Pg This links to a video by Khan Academy that explains how Lenz's Law works through an example.<br />
<br />
https://www.youtube.com/watch?v=Vs3afgStVy4 This links to a video by Grand Illusions that displays Lenz's Law using a magnetic falling down a tube.<br />
<br />
==Examples==<br />
'''Example Using Right Hand Rule'''<br />
<br />
Use the right hand rule to find the non-coulombic electric field in the given situations.<br />
[[File:Non-Coulobmic_Fields.gif]]<br />
<br />
'''Solution'''<br />
<br />
To use the right hand rule: place your thumb in the direction of the <math> -dB </math>, then curl your fingers. The direction in which your fingers curl is the direction of the non-coulombic electric field. The non-coulombic field is represented by the pink arrows.<br />
<br />
===Simple===<br />
<br />
A solenoid has current <math> I_1 </math> flowing around it increasing from 0 to 40A. A plain loop of wire is placed around the solenoid, perpendicular to the axis of the solenoid. An emf is produced, therefore producing an <math> I_2 </math>. Are <math> I_1 </math> and <math> I_2 </math> flowing in the same direction or opposite?<br />
<br />
'''Solution'''<br />
The original current <math> I_1 </math> produced a magnetic field. In order to maintain the conservation of energy and Newton's Third Law, the magnetic field produced by <math> I_2 </math> must oppose this field. This is in accordance with Lenz's Law. Therefore, <math> I_2 </math> must oppose <math> I_1 </math> in direction.<br />
<br />
===Middling===<br />
The magnetic field in this graphic is decreasing at a rate of 5.0mT/s. What is the direction of the current in the circle of wire?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
<br />
'''Solution'''<br />
The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. This is in accordance with Lenz's Law. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
===Difficult===<br />
The magnetic field is decreasing at a rate of 5.0mT/s. The radius of the loop of wire is 5.0m, and the resistance is 5 ohms. What is the magnitude and direction of the current?<br />
<br />
[[File:hm235.jpg]]<br />
<br />
'''Solution'''<br />
<br />
To find the magnitude of the current we must first use the formula <math>\epsilon = -{\frac{d\phi}{dt}} </math> to find the <math>\epsilon</math> representing the emf of the system. We know, more specifically, that <math>\epsilon = -NAcos\theta{\frac{d\phi}{dt}} </math>. Therefore, <math>\epsilon = -1*5.0^2*\pi*1*-5*10^{-3} </math> which resolves to <math>\epsilon = .392699</math>. From there, to find the current we know that <math>I = {\frac{\epsilon}{R}}</math>. Plugging in the values we know we find, <math>I = {\frac{.392699}{5.0}} = .07854A</math>. That is the magnitude of the current. To find the direction we must use Lenz's Law. The current in the circle of wire will produce a magnetic field that needs to supplement the existing diminishing field. Therefore, the magnetic field produced needs to be into the page. Using the right hand rule, to produce a field going into the page the current in the circle of the wire must be in the clockwise direction.<br />
<br />
==Connectedness==<br />
This topic has many applications in the real world that are very interesting. For example, an application for Lenz's Law is to cause rotation to create energy. In an industry setting, Lenz's Law can be applied to electric generators or electric motors. When a current is induced in a generator, the direction of the induced current will flow in opposition of the magnetic field that created it, causing rotation of the generator. <br />
[[File:use235.jpg]]<br />
<br />
Another real world application of Lenz's Law is in electromagnetic braking in vehicles. This process begins with electromagnets inducing eddy currents into the spinning rotor. Magnetic fields that oppose the initial change in magnetic flux are created from these eddy currents (Lenz's Law). This ultimately slows the rotor.<br />
<br />
[[File:engine.jpg]]<br />
<br />
Another example of Lenz's Law in the real world is in Induction stovetops. These cooktops heat up as a result of changing magnetic fields and eddy currents operating according to Lenz's Law.<br />
<br />
[[File:stovetop.jpg]]<br />
<br />
==History==<br />
<br />
Henrich Friefrich Emil Lenz (1804-1865), a Russian physicist of German origin was born in Dorpat, nowadays Tartu, Estonia. Henrich studied chemistry and physics at the University of Dorpat in 1820 after his secondary education. From 1823 to 1826, he traveled with the navigator, Otto von Kotzebue on his third expedition around the world. During this journey he studied climate conditions, and properties of seawater. After his travels, he worked at the University of St. Petersburg, Russia, where he later became the Dean of Mathematics and Physics from 1840 to 1863. In the year of 1831, he started studying electromagnetism, and soon after in 1835, what is known today as Lenz's Law was created. Lenz died on February 10, 1865, just two days before his 61st birthday, after suffering a stroke, while in Rome.<br />
<br />
== See also ==<br />
<br />
Since Lenz's Law and Farady's Law go hand in hand, Faraday's Law would be great supplemental information to read about. Newton's Third Law would also be a topic to read on for further understanding why Lenz's Law exists. <br />
<br />
===Further reading===<br />
<br />
Faraday's Law<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html]<br />
Conservation Laws<br />
[http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html]<br />
<br />
==References==<br />
<br />
https://nationalmaglab.org/education/magnet-academy/history-of-electricity-magnetism/pioneers/heinrich-friedrich-emil-lenz<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/conser.html<br />
http://regentsprep.org/regents/physics/phys08/clenslaw/<br />
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html<br />
http://farside.ph.utexas.edu/teaching/302l/lectures/node85.html<br />
http://www.electrical4u.com/lenz-law-of-electromagnetic-induction/<br />
<br />
[[Category:Which Category did you place this in?]]</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=Reciprocity&diff=28478Reciprocity2017-04-10T00:25:25Z<p>Nromer3: /* Difficult */</p>
<hr />
<div><br />
claimed by Nicole Romer (Spring 2017)<br />
<br />
This topic covers why forces on each other are equal in magnitude. <br />
<br />
[[File:BookForce.JPG|thumb|This is an example of reciprocity. The book is exerting a contact force on the table and the table is exerting a contact force on the book.]]<br />
<br />
==The Main Idea==<br />
<br />
Reciprocity is the idea that the force object 1 exerts on object 2 is the same as the force object 2 exerts on object 1. This idea comes from Newton's Third Law of Motion. Every action has an equal and opposite reaction. Forces are results of interactions. If I put my hand on a table, I am exerting a contact force on the table, but at the same time the table is using a exerting force on me. Though it seems like I am putting in more effort, the forces are the same. Forces come in pairs. The two forces are called "action" and "reaction" pairs. When forces are in these pairs, the magnitude of the two forces equal each other. However, in vector form, the two forces would be in opposite directions of each other, so one force would have a negative sign on it. This applies, to gravitational and electrical forces but not magnetic forces. Contact forces are actually due to electrical forces at the atomic level.<br />
<br />
It is important to remember that because the forces are equal, so are the changes in momentum. Two planets exerting attractive forces on each other will have the same change in momentum over the same amount of time. However if one planet is much larger it will have a much smaller change in velocity then the smaller planet. This is because p = mv and v=p/m. So even though the forces will be the same, they may appear unequal. This is why when we solve problems including objects near earth's surface we often exclude the forces on the earth because compared to the small system they make an extremely small difference in the earth's movement.<br />
<br />
===A Mathematical Model===<br />
<br />
Here is a formulaic representation of reciprocity. <br />
<br />
F1on2=-F2on1. <br />
<br />
The vector form of reciprocity is this:<br />
<br />
<F,0,0> is one force.<br />
<br />
<-F,0,0> is the exact same force but in the opposite direction.<br />
<br />
<br />
This is the equation in vector format. When the vector of one force is in one direction. Usually, the vector is in the other direction<br />
<br />
This equation on the left side. shows that object one is acting on object 2. The equation on the right side shows the reverse.<br />
<br />
==Examples==<br />
<br />
Be sure to show all steps in your solution and include diagrams whenever possible<br />
<br />
===Simple===<br />
<br />
If you exert 20 N on the table, what would be the normal force of the table on you?<br />
<br />
Since you are exerting 20 Newtons, due to reciprocity the table will be exerting a normal force of '''20''' Newtons.<br />
<br />
<br />
If push a box with a force of 15 N, what is the reciprocal force of the box on you?<br />
<br />
The box exerts a force of 15 N on you, in the opposite direction of your force on the box.<br />
<br />
===Middling===<br />
<br />
A 60 kilogram man stands on the surface of the Earth. What is the force Earth exerts on the man? What is the force the man exerts on the Earth?<br />
<br />
60x9.8=588N. Due to reciprocity 588 is the force on both Earth and the man.<br />
<br />
<br />
A box is sitting on Earth's surface. The Earth exerts a force of 196 N on the box. What is the force on the Earth? How much does the box weigh?<br />
<br />
196N/9.8 = 20 kg. Due to reciprocity, the box exerts 196N of force on the earth.<br />
<br />
===Difficult===<br />
<br />
This problem is from our test.<br />
<br />
Two blocks of mass m1(under rod) and m3(above rod) are connected by a rod of mass m2. A constant unknown force F pulls upward on the top block while both blocks and the rod move upward at a constant velocity v near the surface of the Earth. The direction of the gravitational force on each block points down. Find F1on2, the force exerted by the bottom block on the rod.<br />
<br />
Fnet1=0 due to constant v<br />
<br />
F2on1-m1gy=0<br />
<br />
F2on1=m1gy<br />
<br />
F1on2=-m1gy<br />
<br />
<br />
You are pulling a rope with a force of 15 N. The rope is connected to a box on a frictionless surface. The rope and box are moving at a constant rate. Find the force of the rope of the block, the block on the rope, and the rope on you.<br />
<br />
Fnet = 0 (because constant velocity)<br />
<br />
The Force of the rope on you is -15 N (reciprocity)<br />
<br />
The Force of the rope on the box is 15 N<br />
<br />
The Force of the box on the rope is -15 N<br />
<br />
==Connectedness==<br />
# The first physics I ever learned was Newtons laws. Before heading into any science class, I always thought, every reaction gets an equal and opposite reaction. I didnt really understand it. That is a fundamental principle that we use in almost all physics problems. It has been test questions and homework questions. The thing that intrigues me the most is how an ant can be pushing against a rhino and though the rhino is so much bigger, they are still exerting the same force.<br />
#I am an industrial engineering major and though there is very minimal use of physics in that field, I do believe it is something that will help us go about our days knowing that force isn't how much effort you put in but about the action reaction pairs.<br />
#Forces are something we deal with everyday. Everything we touch, me typing this page right now is all the result of forces. An important industry that deals with this is the automobile industry. If we understand the forces of the wheels on the road, we will know how to make wheels that best suit an automobile. <br />
<br />
#This topics is one of the fundamental underlying principles of physics. It applies to pretty much everything in physics.<br />
#Physics applies to almost any major. As an Environmental Engineer reciprocity is important to remember reciprocity, specifically in waste water management. Water pressure (force from water on pipe and force from pipe on water) is important when designing water infrastructure.<br />
#Reciprocity is important to remember in buildings. When creating a structure that can sustain a storm, you have to think about how high winds will change how parts of the structure interact with each other.<br />
<br />
==History==<br />
<br />
Isaac Newton was born in Woolsthorpe, England. When he was a child, one day he was resting under an apple tree when suddenly an apple fell on his head. He thought about why things fall down and not fall back up. He spent years figuring out the phenomenon. After all this, he came up with three laws of motion. This is when he discovered gravitation as a force. Where Newton's Law comes into play is that the Earth is exerting a force on us to stay with it since closer objects exert stronger forces on each other. We are also exerting a force on Earth so that we stay on the ground and don't go flying off. The date of this story is not known, and some even believe it to be a myth. However William Stukeley, author of ''Memoirs of Sir Isaac Newton's Life'' noted that he had a conversation with Newton and Newton talked about why an apple falls to the ground due to gravitational interaction.<br />
<br />
== See also ==<br />
<br />
===Further reading===<br />
<br />
:'''1:'''http://www.physicsclassroom.com/class/newtlaws/Lesson-4/Newton-s-Third-Law<br />
<br />
:'''2:'''Matter and Interactions By Ruth W. Chabay, Bruce A. Sherwood - Chapter 3.4<br />
<br />
===External links===<br />
<br />
https://www.youtube.com/watch?v=NfuKfbpkIrQ<br />
<br />
==References==<br />
<br />
:'''1:''' http://www.mainlesson.com/display.php?author=baldwin&book=thirty&story=newton<br />
<br />
:'''2:''' https://www.newscientist.com/blogs/culturelab/2010/01/newtons-apple-the-real-story.html<br />
<br />
:'''3:''' http://www.physicsclassroom.com/class/newtlaws/Lesson-4/Newton-s-Third-Law<br />
<br />
:'''4:''' Matter and Interactions By Ruth W. Chabay, Bruce A. Sherwood - Chapter 3.4<br />
<br />
[[Category:Which Category did you place this in?]]</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=Reciprocity&diff=28453Reciprocity2017-04-10T00:14:37Z<p>Nromer3: /* Simple */</p>
<hr />
<div><br />
claimed by Nicole Romer (Spring 2017)<br />
<br />
This topic covers why forces on each other are equal in magnitude. <br />
<br />
[[File:BookForce.JPG|thumb|This is an example of reciprocity. The book is exerting a contact force on the table and the table is exerting a contact force on the book.]]<br />
<br />
==The Main Idea==<br />
<br />
Reciprocity is the idea that the force object 1 exerts on object 2 is the same as the force object 2 exerts on object 1. This idea comes from Newton's Third Law of Motion. Every action has an equal and opposite reaction. Forces are results of interactions. If I put my hand on a table, I am exerting a contact force on the table, but at the same time the table is using a exerting force on me. Though it seems like I am putting in more effort, the forces are the same. Forces come in pairs. The two forces are called "action" and "reaction" pairs. When forces are in these pairs, the magnitude of the two forces equal each other. However, in vector form, the two forces would be in opposite directions of each other, so one force would have a negative sign on it. This applies, to gravitational and electrical forces but not magnetic forces. Contact forces are actually due to electrical forces at the atomic level.<br />
<br />
It is important to remember that because the forces are equal, so are the changes in momentum. Two planets exerting attractive forces on each other will have the same change in momentum over the same amount of time. However if one planet is much larger it will have a much smaller change in velocity then the smaller planet. This is because p = mv and v=p/m. So even though the forces will be the same, they may appear unequal. This is why when we solve problems including objects near earth's surface we often exclude the forces on the earth because compared to the small system they make an extremely small difference in the earth's movement.<br />
<br />
===A Mathematical Model===<br />
<br />
Here is a formulaic representation of reciprocity. <br />
<br />
F1on2=-F2on1. <br />
<br />
The vector form of reciprocity is this:<br />
<br />
<F,0,0> is one force.<br />
<br />
<-F,0,0> is the exact same force but in the opposite direction.<br />
<br />
<br />
This is the equation in vector format. When the vector of one force is in one direction. Usually, the vector is in the other direction<br />
<br />
This equation on the left side. shows that object one is acting on object 2. The equation on the right side shows the reverse.<br />
<br />
==Examples==<br />
<br />
Be sure to show all steps in your solution and include diagrams whenever possible<br />
<br />
===Simple===<br />
<br />
If you exert 20 N on the table, what would be the normal force of the table on you?<br />
<br />
Since you are exerting 20 Newtons, due to reciprocity the table will be exerting a normal force of '''20''' Newtons.<br />
<br />
<br />
If push a box with a force of 15 N, what is the reciprocal force of the box on you?<br />
<br />
The box exerts a force of 15 N on you, in the opposite direction of your force on the box.<br />
<br />
===Middling===<br />
<br />
A 60 kilogram man stands on the surface of the Earth. What is the force Earth exerts on the man? What is the force the man exerts on the Earth?<br />
<br />
60x9.8=588N. Due to reciprocity 588 is the force on both Earth and the man.<br />
<br />
<br />
A box is sitting on Earth's surface. The Earth exerts a force of 196 N on the box. What is the force on the Earth? How much does the box weigh?<br />
<br />
196N/9.8 = 20 kg. Due to reciprocity, the box exerts 196N of force on the earth.<br />
<br />
===Difficult===<br />
<br />
This problem is from our test.<br />
<br />
Two blocks of mass m1(under rod) and m3(above rod) are connected by a rod of mass m2. A constant unknown force F pulls upward on the top block while both blocks and the rod move upward at a constant velocity v near the surface of the Earth. The direction of the gravitational force on each block points down. Find F1on2, the force exerted by the bottom block on the rod.<br />
<br />
Fnet1=0 due to constant v<br />
<br />
F2on1-m1gy=0<br />
<br />
F2on1=m1gy<br />
<br />
F1on2=-m1gy<br />
<br />
<br />
<br />
==Connectedness==<br />
# The first physics I ever learned was Newtons laws. Before heading into any science class, I always thought, every reaction gets an equal and opposite reaction. I didnt really understand it. That is a fundamental principle that we use in almost all physics problems. It has been test questions and homework questions. The thing that intrigues me the most is how an ant can be pushing against a rhino and though the rhino is so much bigger, they are still exerting the same force.<br />
#I am an industrial engineering major and though there is very minimal use of physics in that field, I do believe it is something that will help us go about our days knowing that force isn't how much effort you put in but about the action reaction pairs.<br />
#Forces are something we deal with everyday. Everything we touch, me typing this page right now is all the result of forces. An important industry that deals with this is the automobile industry. If we understand the forces of the wheels on the road, we will know how to make wheels that best suit an automobile. <br />
<br />
#This topics is one of the fundamental underlying principles of physics. It applies to pretty much everything in physics.<br />
#Physics applies to almost any major. As an Environmental Engineer reciprocity is important to remember reciprocity, specifically in waste water management. Water pressure (force from water on pipe and force from pipe on water) is important when designing water infrastructure.<br />
#Reciprocity is important to remember in buildings. When creating a structure that can sustain a storm, you have to think about how high winds will change how parts of the structure interact with each other.<br />
<br />
==History==<br />
<br />
Isaac Newton was born in Woolsthorpe, England. When he was a child, one day he was resting under an apple tree when suddenly an apple fell on his head. He thought about why things fall down and not fall back up. He spent years figuring out the phenomenon. After all this, he came up with three laws of motion. This is when he discovered gravitation as a force. Where Newton's Law comes into play is that the Earth is exerting a force on us to stay with it since closer objects exert stronger forces on each other. We are also exerting a force on Earth so that we stay on the ground and don't go flying off. The date of this story is not known, and some even believe it to be a myth. However William Stukeley, author of ''Memoirs of Sir Isaac Newton's Life'' noted that he had a conversation with Newton and Newton talked about why an apple falls to the ground due to gravitational interaction.<br />
<br />
== See also ==<br />
<br />
===Further reading===<br />
<br />
:'''1:'''http://www.physicsclassroom.com/class/newtlaws/Lesson-4/Newton-s-Third-Law<br />
<br />
:'''2:'''Matter and Interactions By Ruth W. Chabay, Bruce A. Sherwood - Chapter 3.4<br />
<br />
===External links===<br />
<br />
https://www.youtube.com/watch?v=NfuKfbpkIrQ<br />
<br />
==References==<br />
<br />
:'''1:''' http://www.mainlesson.com/display.php?author=baldwin&book=thirty&story=newton<br />
<br />
:'''2:''' https://www.newscientist.com/blogs/culturelab/2010/01/newtons-apple-the-real-story.html<br />
<br />
:'''3:''' http://www.physicsclassroom.com/class/newtlaws/Lesson-4/Newton-s-Third-Law<br />
<br />
:'''4:''' Matter and Interactions By Ruth W. Chabay, Bruce A. Sherwood - Chapter 3.4<br />
<br />
[[Category:Which Category did you place this in?]]</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=Reciprocity&diff=28440Reciprocity2017-04-10T00:08:05Z<p>Nromer3: /* Middling */</p>
<hr />
<div><br />
claimed by Nicole Romer (Spring 2017)<br />
<br />
This topic covers why forces on each other are equal in magnitude. <br />
<br />
[[File:BookForce.JPG|thumb|This is an example of reciprocity. The book is exerting a contact force on the table and the table is exerting a contact force on the book.]]<br />
<br />
==The Main Idea==<br />
<br />
Reciprocity is the idea that the force object 1 exerts on object 2 is the same as the force object 2 exerts on object 1. This idea comes from Newton's Third Law of Motion. Every action has an equal and opposite reaction. Forces are results of interactions. If I put my hand on a table, I am exerting a contact force on the table, but at the same time the table is using a exerting force on me. Though it seems like I am putting in more effort, the forces are the same. Forces come in pairs. The two forces are called "action" and "reaction" pairs. When forces are in these pairs, the magnitude of the two forces equal each other. However, in vector form, the two forces would be in opposite directions of each other, so one force would have a negative sign on it. This applies, to gravitational and electrical forces but not magnetic forces. Contact forces are actually due to electrical forces at the atomic level.<br />
<br />
It is important to remember that because the forces are equal, so are the changes in momentum. Two planets exerting attractive forces on each other will have the same change in momentum over the same amount of time. However if one planet is much larger it will have a much smaller change in velocity then the smaller planet. This is because p = mv and v=p/m. So even though the forces will be the same, they may appear unequal. This is why when we solve problems including objects near earth's surface we often exclude the forces on the earth because compared to the small system they make an extremely small difference in the earth's movement.<br />
<br />
===A Mathematical Model===<br />
<br />
Here is a formulaic representation of reciprocity. <br />
<br />
F1on2=-F2on1. <br />
<br />
The vector form of reciprocity is this:<br />
<br />
<F,0,0> is one force.<br />
<br />
<-F,0,0> is the exact same force but in the opposite direction.<br />
<br />
<br />
This is the equation in vector format. When the vector of one force is in one direction. Usually, the vector is in the other direction<br />
<br />
This equation on the left side. shows that object one is acting on object 2. The equation on the right side shows the reverse.<br />
<br />
==Examples==<br />
<br />
Be sure to show all steps in your solution and include diagrams whenever possible<br />
<br />
===Simple===<br />
<br />
If you exert 20 N on the table, what would be the normal force of the table on you?<br />
<br />
Since you are exerting 20 Newtons, due to reciprocity the table will be exerting a normal force of '''20''' Newtons.<br />
<br />
===Middling===<br />
<br />
A 60 kilogram man stands on the surface of the Earth. What is the force Earth exerts on the man? What is the force the man exerts on the Earth?<br />
<br />
60x9.8=588N. Due to reciprocity 588 is the force on both Earth and the man.<br />
<br />
<br />
A box is sitting on Earth's surface. The Earth exerts a force of 196 N on the box. What is the force on the Earth? How much does the box weigh?<br />
<br />
196N/9.8 = 20 kg. Due to reciprocity, the box exerts 196N of force on the earth.<br />
<br />
===Difficult===<br />
<br />
This problem is from our test.<br />
<br />
Two blocks of mass m1(under rod) and m3(above rod) are connected by a rod of mass m2. A constant unknown force F pulls upward on the top block while both blocks and the rod move upward at a constant velocity v near the surface of the Earth. The direction of the gravitational force on each block points down. Find F1on2, the force exerted by the bottom block on the rod.<br />
<br />
Fnet1=0 due to constant v<br />
<br />
F2on1-m1gy=0<br />
<br />
F2on1=m1gy<br />
<br />
F1on2=-m1gy<br />
<br />
<br />
<br />
==Connectedness==<br />
# The first physics I ever learned was Newtons laws. Before heading into any science class, I always thought, every reaction gets an equal and opposite reaction. I didnt really understand it. That is a fundamental principle that we use in almost all physics problems. It has been test questions and homework questions. The thing that intrigues me the most is how an ant can be pushing against a rhino and though the rhino is so much bigger, they are still exerting the same force.<br />
#I am an industrial engineering major and though there is very minimal use of physics in that field, I do believe it is something that will help us go about our days knowing that force isn't how much effort you put in but about the action reaction pairs.<br />
#Forces are something we deal with everyday. Everything we touch, me typing this page right now is all the result of forces. An important industry that deals with this is the automobile industry. If we understand the forces of the wheels on the road, we will know how to make wheels that best suit an automobile. <br />
<br />
#This topics is one of the fundamental underlying principles of physics. It applies to pretty much everything in physics.<br />
#Physics applies to almost any major. As an Environmental Engineer reciprocity is important to remember reciprocity, specifically in waste water management. Water pressure (force from water on pipe and force from pipe on water) is important when designing water infrastructure.<br />
#Reciprocity is important to remember in buildings. When creating a structure that can sustain a storm, you have to think about how high winds will change how parts of the structure interact with each other.<br />
<br />
==History==<br />
<br />
Isaac Newton was born in Woolsthorpe, England. When he was a child, one day he was resting under an apple tree when suddenly an apple fell on his head. He thought about why things fall down and not fall back up. He spent years figuring out the phenomenon. After all this, he came up with three laws of motion. This is when he discovered gravitation as a force. Where Newton's Law comes into play is that the Earth is exerting a force on us to stay with it since closer objects exert stronger forces on each other. We are also exerting a force on Earth so that we stay on the ground and don't go flying off. The date of this story is not known, and some even believe it to be a myth. However William Stukeley, author of ''Memoirs of Sir Isaac Newton's Life'' noted that he had a conversation with Newton and Newton talked about why an apple falls to the ground due to gravitational interaction.<br />
<br />
== See also ==<br />
<br />
===Further reading===<br />
<br />
:'''1:'''http://www.physicsclassroom.com/class/newtlaws/Lesson-4/Newton-s-Third-Law<br />
<br />
:'''2:'''Matter and Interactions By Ruth W. Chabay, Bruce A. Sherwood - Chapter 3.4<br />
<br />
===External links===<br />
<br />
https://www.youtube.com/watch?v=NfuKfbpkIrQ<br />
<br />
==References==<br />
<br />
:'''1:''' http://www.mainlesson.com/display.php?author=baldwin&book=thirty&story=newton<br />
<br />
:'''2:''' https://www.newscientist.com/blogs/culturelab/2010/01/newtons-apple-the-real-story.html<br />
<br />
:'''3:''' http://www.physicsclassroom.com/class/newtlaws/Lesson-4/Newton-s-Third-Law<br />
<br />
:'''4:''' Matter and Interactions By Ruth W. Chabay, Bruce A. Sherwood - Chapter 3.4<br />
<br />
[[Category:Which Category did you place this in?]]</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=Reciprocity&diff=28425Reciprocity2017-04-10T00:02:40Z<p>Nromer3: </p>
<hr />
<div><br />
claimed by Nicole Romer (Spring 2017)<br />
<br />
This topic covers why forces on each other are equal in magnitude. <br />
<br />
[[File:BookForce.JPG|thumb|This is an example of reciprocity. The book is exerting a contact force on the table and the table is exerting a contact force on the book.]]<br />
<br />
==The Main Idea==<br />
<br />
Reciprocity is the idea that the force object 1 exerts on object 2 is the same as the force object 2 exerts on object 1. This idea comes from Newton's Third Law of Motion. Every action has an equal and opposite reaction. Forces are results of interactions. If I put my hand on a table, I am exerting a contact force on the table, but at the same time the table is using a exerting force on me. Though it seems like I am putting in more effort, the forces are the same. Forces come in pairs. The two forces are called "action" and "reaction" pairs. When forces are in these pairs, the magnitude of the two forces equal each other. However, in vector form, the two forces would be in opposite directions of each other, so one force would have a negative sign on it. This applies, to gravitational and electrical forces but not magnetic forces. Contact forces are actually due to electrical forces at the atomic level.<br />
<br />
It is important to remember that because the forces are equal, so are the changes in momentum. Two planets exerting attractive forces on each other will have the same change in momentum over the same amount of time. However if one planet is much larger it will have a much smaller change in velocity then the smaller planet. This is because p = mv and v=p/m. So even though the forces will be the same, they may appear unequal. This is why when we solve problems including objects near earth's surface we often exclude the forces on the earth because compared to the small system they make an extremely small difference in the earth's movement.<br />
<br />
===A Mathematical Model===<br />
<br />
Here is a formulaic representation of reciprocity. <br />
<br />
F1on2=-F2on1. <br />
<br />
The vector form of reciprocity is this:<br />
<br />
<F,0,0> is one force.<br />
<br />
<-F,0,0> is the exact same force but in the opposite direction.<br />
<br />
<br />
This is the equation in vector format. When the vector of one force is in one direction. Usually, the vector is in the other direction<br />
<br />
This equation on the left side. shows that object one is acting on object 2. The equation on the right side shows the reverse.<br />
<br />
==Examples==<br />
<br />
Be sure to show all steps in your solution and include diagrams whenever possible<br />
<br />
===Simple===<br />
<br />
If you exert 20 N on the table, what would be the normal force of the table on you?<br />
<br />
Since you are exerting 20 Newtons, due to reciprocity the table will be exerting a normal force of '''20''' Newtons.<br />
<br />
===Middling===<br />
<br />
A 60 kilogram man stands on the surface of the Earth. What is the force Earth exerts on the man? What is the force the man exerts on the Earth?<br />
<br />
60x9.8=588N. Due to reciprocity 588 is the force on both Earth and the man.<br />
<br />
===Difficult===<br />
<br />
This problem is from our test.<br />
<br />
Two blocks of mass m1(under rod) and m3(above rod) are connected by a rod of mass m2. A constant unknown force F pulls upward on the top block while both blocks and the rod move upward at a constant velocity v near the surface of the Earth. The direction of the gravitational force on each block points down. Find F1on2, the force exerted by the bottom block on the rod.<br />
<br />
Fnet1=0 due to constant v<br />
<br />
F2on1-m1gy=0<br />
<br />
F2on1=m1gy<br />
<br />
F1on2=-m1gy<br />
<br />
<br />
<br />
==Connectedness==<br />
# The first physics I ever learned was Newtons laws. Before heading into any science class, I always thought, every reaction gets an equal and opposite reaction. I didnt really understand it. That is a fundamental principle that we use in almost all physics problems. It has been test questions and homework questions. The thing that intrigues me the most is how an ant can be pushing against a rhino and though the rhino is so much bigger, they are still exerting the same force.<br />
#I am an industrial engineering major and though there is very minimal use of physics in that field, I do believe it is something that will help us go about our days knowing that force isn't how much effort you put in but about the action reaction pairs.<br />
#Forces are something we deal with everyday. Everything we touch, me typing this page right now is all the result of forces. An important industry that deals with this is the automobile industry. If we understand the forces of the wheels on the road, we will know how to make wheels that best suit an automobile. <br />
<br />
#This topics is one of the fundamental underlying principles of physics. It applies to pretty much everything in physics.<br />
#Physics applies to almost any major. As an Environmental Engineer reciprocity is important to remember reciprocity, specifically in waste water management. Water pressure (force from water on pipe and force from pipe on water) is important when designing water infrastructure.<br />
#Reciprocity is important to remember in buildings. When creating a structure that can sustain a storm, you have to think about how high winds will change how parts of the structure interact with each other.<br />
<br />
==History==<br />
<br />
Isaac Newton was born in Woolsthorpe, England. When he was a child, one day he was resting under an apple tree when suddenly an apple fell on his head. He thought about why things fall down and not fall back up. He spent years figuring out the phenomenon. After all this, he came up with three laws of motion. This is when he discovered gravitation as a force. Where Newton's Law comes into play is that the Earth is exerting a force on us to stay with it since closer objects exert stronger forces on each other. We are also exerting a force on Earth so that we stay on the ground and don't go flying off. The date of this story is not known, and some even believe it to be a myth. However William Stukeley, author of ''Memoirs of Sir Isaac Newton's Life'' noted that he had a conversation with Newton and Newton talked about why an apple falls to the ground due to gravitational interaction.<br />
<br />
== See also ==<br />
<br />
===Further reading===<br />
<br />
:'''1:'''http://www.physicsclassroom.com/class/newtlaws/Lesson-4/Newton-s-Third-Law<br />
<br />
:'''2:'''Matter and Interactions By Ruth W. Chabay, Bruce A. Sherwood - Chapter 3.4<br />
<br />
===External links===<br />
<br />
https://www.youtube.com/watch?v=NfuKfbpkIrQ<br />
<br />
==References==<br />
<br />
:'''1:''' http://www.mainlesson.com/display.php?author=baldwin&book=thirty&story=newton<br />
<br />
:'''2:''' https://www.newscientist.com/blogs/culturelab/2010/01/newtons-apple-the-real-story.html<br />
<br />
:'''3:''' http://www.physicsclassroom.com/class/newtlaws/Lesson-4/Newton-s-Third-Law<br />
<br />
:'''4:''' Matter and Interactions By Ruth W. Chabay, Bruce A. Sherwood - Chapter 3.4<br />
<br />
[[Category:Which Category did you place this in?]]</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=Reciprocity&diff=28388Reciprocity2017-04-09T23:52:09Z<p>Nromer3: </p>
<hr />
<div><br />
claimed by Nicole Romer (Spring 2017)<br />
<br />
This topic covers why forces on each other are equal in magnitude. <br />
<br />
[[File:BookForce.JPG|thumb|This is an example of reciprocity. The book is exerting a contact force on the table and the table is exerting a contact force on the book.]]<br />
<br />
==The Main Idea==<br />
<br />
Reciprocity is the idea that the force object 1 exerts on object 2 is the same as the force object 2 exerts on object 1. This idea comes from Newton's Third Law of Motion. Every action has an equal and opposite reaction. Forces are results of interactions. If I put my hand on a table, I am exerting a contact force on the table, but at the same time the table is using a exerting force on me. Though it seems like I am putting in more effort, the forces are the same. Forces come in pairs. The two forces are called "action" and "reaction" pairs. When forces are in these pairs, the magnitude of the two forces equal each other. However, in vector form, the two forces would be in opposite directions of each other, so one force would have a negative sign on it. This applies, to every kind of force, gravitational, electrical, ect.<br />
<br />
It is important to remember that because the forces are equal, so are the changes in momentum. Two planets exerting attractive forces on each other will have the same change in momentum over the same amount of time. However if one planet is much larger it will have a much smaller change in velocity then the smaller planet. This is because p = mv and v=p/m. So even though the forces will be the same, they may appear unequal. This is why when we solve problems including objects near earth's surface we often exclude the forces on the earth because compared to the small system they make an extremely small difference in the earth's movement.<br />
<br />
===A Mathematical Model===<br />
<br />
Here is a formulaic representation of reciprocity. <br />
<br />
F1on2=-F2on1. <br />
<br />
The vector form of reciprocity is this:<br />
<br />
<F,0,0> is one force.<br />
<br />
<-F,0,0> is the exact same force but in the opposite direction.<br />
<br />
<br />
This is the equation in vector format. When the vector of one force is in one direction. Usually, the vector is in the other direction<br />
<br />
This equation on the left side. shows that object one is acting on object 2. The equation on the right side shows the reverse.<br />
<br />
==Examples==<br />
<br />
Be sure to show all steps in your solution and include diagrams whenever possible<br />
<br />
===Simple===<br />
<br />
If you exert 20 N on the table, what would be the normal force of the table on you?<br />
<br />
Since you are exerting 20 Newtons, due to reciprocity the table will be exerting a normal force of '''20''' Newtons.<br />
<br />
===Middling===<br />
<br />
A 60 kilogram man stands on the surface of the Earth. What is the force Earth exerts on the man? What is the force the man exerts on the Earth?<br />
<br />
60x9.8=588N. Due to reciprocity 588 is the force on both Earth and the man.<br />
<br />
===Difficult===<br />
<br />
This problem is from our test.<br />
<br />
Two blocks of mass m1(under rod) and m3(above rod) are connected by a rod of mass m2. A constant unknown force F pulls upward on the top block while both blocks and the rod move upward at a constant velocity v near the surface of the Earth. The direction of the gravitational force on each block points down. Find F1on2, the force exerted by the bottom block on the rod.<br />
<br />
Fnet1=0 due to constant v<br />
<br />
F2on1-m1gy=0<br />
<br />
F2on1=m1gy<br />
<br />
F1on2=-m1gy<br />
<br />
<br />
<br />
==Connectedness==<br />
# The first physics I ever learned was Newtons laws. Before heading into any science class, I always thought, every reaction gets an equal and opposite reaction. I didnt really understand it. That is a fundamental principle that we use in almost all physics problems. It has been test questions and homework questions. The thing that intrigues me the most is how an ant can be pushing against a rhino and though the rhino is so much bigger, they are still exerting the same force.<br />
#I am an industrial engineering major and though there is very minimal use of physics in that field, I do believe it is something that will help us go about our days knowing that force isn't how much effort you put in but about the action reaction pairs.<br />
#Forces are something we deal with everyday. Everything we touch, me typing this page right now is all the result of forces. An important industry that deals with this is the automobile industry. If we understand the forces of the wheels on the road, we will know how to make wheels that best suit an automobile. <br />
<br />
==History==<br />
<br />
Isaac Newton was born in Woolsthorpe, England. When he was a child, one day he was resting under an apple tree when suddenly an apple fell on his head. He thought about why things fall down and not fall back up. He spent years figuring out the phenomenon. After all this, he came up with three laws of motion. This is when he discovered gravitation as a force. Where Newton's Law comes into play is that the Earth is exerting a force on us to stay with it since closer objects exert stronger forces on each other. We are also exerting a force on Earth so that we stay on the ground and don't go flying off. The date of this story is not known, and some even believe it to be a myth. However William Stukeley, author of ''Memoirs of Sir Isaac Newton's Life'' noted that he had a conversation with Newton and Newton talked about why an apple falls to the ground due to gravitational interaction.<br />
<br />
== See also ==<br />
<br />
===Further reading===<br />
<br />
:'''1:'''http://www.physicsclassroom.com/class/newtlaws/Lesson-4/Newton-s-Third-Law<br />
<br />
:'''2:'''Matter and Interactions By Ruth W. Chabay, Bruce A. Sherwood - Chapter 3.4<br />
<br />
===External links===<br />
<br />
https://www.youtube.com/watch?v=NfuKfbpkIrQ<br />
<br />
==References==<br />
<br />
:'''1:''' http://www.mainlesson.com/display.php?author=baldwin&book=thirty&story=newton<br />
<br />
:'''2:''' https://www.newscientist.com/blogs/culturelab/2010/01/newtons-apple-the-real-story.html<br />
<br />
:'''3:''' http://www.physicsclassroom.com/class/newtlaws/Lesson-4/Newton-s-Third-Law<br />
<br />
:'''4:''' Matter and Interactions By Ruth W. Chabay, Bruce A. Sherwood - Chapter 3.4<br />
<br />
[[Category:Which Category did you place this in?]]</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=Reciprocity&diff=28379Reciprocity2017-04-09T23:49:37Z<p>Nromer3: </p>
<hr />
<div><br />
claimed by Nicole Romer (Spring 2017)<br />
<br />
This topic covers why forces on each other are equal in magnitude. <br />
<br />
[[File:BookForce.JPG|thumb|This is an example of reciprocity. The book is exerting a contact force on the table and the table is exerting a contact force on the book.]]<br />
<br />
==The Main Idea==<br />
<br />
Reciprocity is the idea that the force object 1 exerts on object 2 is the same as the force object 2 exerts on object 1. This idea comes from Newton's Third Law of Motion. Every action has an equal and opposite reaction. Forces are results of interactions. If I put my hand on a table, I am exerting a contact force on the table, but at the same time the table is using a exerting force on me. Though it seems like I am putting in more effort, the forces are the same. Forces come in pairs. The two forces are called "action" and "reaction" pairs. When forces are in these pairs, the magnitude of the two forces equal each other. However, in vector form, the two forces would be in opposite directions of each other, so one force would have a negative sign on it. <br />
<br />
It is important to remember that because the forces are equal, so are the changes in momentum. Two planets exerting attractive forces on each other will have the same change in momentum over the same amount of time. However if one planet is much larger it will have a much smaller change in velocity then the smaller planet. This is because p = mv and v=p/m. So even though the forces will be the same, they may appear unequal. This is why when we solve problems including objects near earth's surface we often exclude the forces on the earth because compared to the small system they make an extremely small difference in the earth's movement.<br />
<br />
===A Mathematical Model===<br />
<br />
Here is a formulaic representation of reciprocity. <br />
<br />
F1on2=-F2on1. <br />
<br />
The vector form of reciprocity is this:<br />
<br />
<F,0,0> is one force.<br />
<br />
<-F,0,0> is the exact same force but in the opposite direction.<br />
<br />
<br />
This is the equation in vector format. When the vector of one force is in one direction. Usually, the vector is in the other direction<br />
<br />
This equation on the left side. shows that object one is acting on object 2. The equation on the right side shows the reverse.<br />
<br />
==Examples==<br />
<br />
Be sure to show all steps in your solution and include diagrams whenever possible<br />
<br />
===Simple===<br />
<br />
If you exert 20 N on the table, what would be the normal force of the table on you?<br />
<br />
Since you are exerting 20 Newtons, due to reciprocity the table will be exerting a normal force of '''20''' Newtons.<br />
<br />
===Middling===<br />
<br />
A 60 kilogram man stands on the surface of the Earth. What is the force Earth exerts on the man? What is the force the man exerts on the Earth?<br />
<br />
60x9.8=588N. Due to reciprocity 588 is the force on both Earth and the man.<br />
<br />
===Difficult===<br />
<br />
This problem is from our test.<br />
<br />
Two blocks of mass m1(under rod) and m3(above rod) are connected by a rod of mass m2. A constant unknown force F pulls upward on the top block while both blocks and the rod move upward at a constant velocity v near the surface of the Earth. The direction of the gravitational force on each block points down. Find F1on2, the force exerted by the bottom block on the rod.<br />
<br />
Fnet1=0 due to constant v<br />
<br />
F2on1-m1gy=0<br />
<br />
F2on1=m1gy<br />
<br />
F1on2=-m1gy<br />
<br />
<br />
<br />
==Connectedness==<br />
# The first physics I ever learned was Newtons laws. Before heading into any science class, I always thought, every reaction gets an equal and opposite reaction. I didnt really understand it. That is a fundamental principle that we use in almost all physics problems. It has been test questions and homework questions. The thing that intrigues me the most is how an ant can be pushing against a rhino and though the rhino is so much bigger, they are still exerting the same force.<br />
#I am an industrial engineering major and though there is very minimal use of physics in that field, I do believe it is something that will help us go about our days knowing that force isn't how much effort you put in but about the action reaction pairs.<br />
#Forces are something we deal with everyday. Everything we touch, me typing this page right now is all the result of forces. An important industry that deals with this is the automobile industry. If we understand the forces of the wheels on the road, we will know how to make wheels that best suit an automobile. <br />
<br />
==History==<br />
<br />
Isaac Newton was born in Woolsthorpe, England. When he was a child, one day he was resting under an apple tree when suddenly an apple fell on his head. He thought about why things fall down and not fall back up. He spent years figuring out the phenomenon. After all this, he came up with three laws of motion. This is when he discovered gravitation as a force. Where Newton's Law comes into play is that the Earth is exerting a force on us to stay with it since closer objects exert stronger forces on each other. We are also exerting a force on Earth so that we stay on the ground and don't go flying off. The date of this story is not known, and some even believe it to be a myth. However William Stukeley, author of ''Memoirs of Sir Isaac Newton's Life'' noted that he had a conversation with Newton and Newton talked about why an apple falls to the ground due to gravitational interaction.<br />
<br />
== See also ==<br />
<br />
===Further reading===<br />
<br />
:'''1:'''http://www.physicsclassroom.com/class/newtlaws/Lesson-4/Newton-s-Third-Law<br />
<br />
:'''2:'''Matter and Interactions By Ruth W. Chabay, Bruce A. Sherwood - Chapter 3.4<br />
<br />
===External links===<br />
<br />
https://www.youtube.com/watch?v=NfuKfbpkIrQ<br />
<br />
==References==<br />
<br />
:'''1:''' http://www.mainlesson.com/display.php?author=baldwin&book=thirty&story=newton<br />
<br />
:'''2:''' https://www.newscientist.com/blogs/culturelab/2010/01/newtons-apple-the-real-story.html<br />
<br />
:'''3:''' http://www.physicsclassroom.com/class/newtlaws/Lesson-4/Newton-s-Third-Law<br />
<br />
:'''4:''' Matter and Interactions By Ruth W. Chabay, Bruce A. Sherwood - Chapter 3.4<br />
<br />
[[Category:Which Category did you place this in?]]</div>Nromer3http://www.physicsbook.gatech.edu/index.php?title=Reciprocity&diff=28244Reciprocity2017-04-09T22:08:08Z<p>Nromer3: </p>
<hr />
<div><br />
claimed by Nicole Romer (Spring 2017)<br />
<br />
This topic covers why forces on each other are equal in magnitude. <br />
<br />
[[File:BookForce.JPG|thumb|This is an example of reciprocity. The book is exerting a contact force on the table and the table is exerting a contact force on the book.]]<br />
<br />
==The Main Idea==<br />
<br />
Reciprocity is the idea that the force object 1 exerts on object 2 is the same as the force object 2 exerts on object 1. This idea comes from Newton's Third Law of Motion. Every action has an equal and opposite reaction. Forces are results of interactions. If I put my hand on a table, I am exerting a contact force on the table, but at the same time the table is using a exerting force on me. Though it seems like I am putting in more effort, the forces are the same. Forces come in pairs. The two forces are called "action" and "reaction" pairs. When forces are in these pairs, the magnitude of the two forces equal each other. However, in vector form, the two forces would be in opposite directions of each other, so one force would have a negative sign on it. <br />
<br />
===A Mathematical Model===<br />
<br />
Here is a formulaic representation of reciprocity. <br />
<br />
F1on2=-F2on1. <br />
<br />
The vector form of reciprocity is this:<br />
<br />
<F,0,0> is one force.<br />
<br />
<-F,0,0> is the exact same force but in the opposite direction.<br />
<br />
<br />
This is the equation in vector format. When the vector of one force is in one direction. Usually, the vector is in the other direction<br />
<br />
This equation on the left side. shows that object one is acting on object 2. The equation on the right side shows the reverse.<br />
<br />
==Examples==<br />
<br />
Be sure to show all steps in your solution and include diagrams whenever possible<br />
<br />
===Simple===<br />
<br />
If you exert 20 N on the table, what would be the normal force of the table on you?<br />
<br />
Since you are exerting 20 Newtons, due to reciprocity the table will be exerting a normal force of '''20''' Newtons.<br />
<br />
===Middling===<br />
<br />
A 60 kilogram man stands on the surface of the Earth. What is the force Earth exerts on the man? What is the force the man exerts on the Earth?<br />
<br />
60x9.8=588N. Due to reciprocity 588 is the force on both Earth and the man.<br />
<br />
===Difficult===<br />
<br />
This problem is from our test.<br />
<br />
Two blocks of mass m1(under rod) and m3(above rod) are connected by a rod of mass m2. A constant unknown force F pulls upward on the top block while both blocks and the rod move upward at a constant velocity v near the surface of the Earth. The direction of the gravitational force on each block points down. Find F1on2, the force exerted by the bottom block on the rod.<br />
<br />
Fnet1=0 due to constant v<br />
<br />
F2on1-m1gy=0<br />
<br />
F2on1=m1gy<br />
<br />
F1on2=-m1gy<br />
<br />
<br />
<br />
==Connectedness==<br />
# The first physics I ever learned was Newtons laws. Before heading into any science class, I always thought, every reaction gets an equal and opposite reaction. I didnt really understand it. That is a fundamental principle that we use in almost all physics problems. It has been test questions and homework questions. The thing that intrigues me the most is how an ant can be pushing against a rhino and though the rhino is so much bigger, they are still exerting the same force.<br />
#I am an industrial engineering major and though there is very minimal use of physics in that field, I do believe it is something that will help us go about our days knowing that force isn't how much effort you put in but about the action reaction pairs.<br />
#Forces are something we deal with everyday. Everything we touch, me typing this page right now is all the result of forces. An important industry that deals with this is the automobile industry. If we understand the forces of the wheels on the road, we will know how to make wheels that best suit an automobile. <br />
<br />
==History==<br />
<br />
Isaac Newton was born in Woolsthorpe, England. When he was a child, one day he was resting under an apple tree when suddenly an apple fell on his head. He thought about why things fall down and not fall back up. He spent years figuring out the phenomenon. After all this, he came up with three laws of motion. This is when he discovered gravitation as a force. Where Newton's Law comes into play is that the Earth is exerting a force on us to stay with it since closer objects exert stronger forces on each other. We are also exerting a force on Earth so that we stay on the ground and don't go flying off. The date of this story is not known, and some even believe it to be a myth. However William Stukeley, author of ''Memoirs of Sir Isaac Newton's Life'' noted that he had a conversation with Newton and Newton talked about why an apple falls to the ground due to gravitational interaction.<br />
<br />
== See also ==<br />
<br />
===Further reading===<br />
<br />
:'''1:'''http://www.physicsclassroom.com/class/newtlaws/Lesson-4/Newton-s-Third-Law<br />
<br />
:'''2:'''Matter and Interactions By Ruth W. Chabay, Bruce A. Sherwood - Chapter 3.4<br />
<br />
===External links===<br />
<br />
https://www.youtube.com/watch?v=NfuKfbpkIrQ<br />
<br />
==References==<br />
<br />
:'''1:''' http://www.mainlesson.com/display.php?author=baldwin&book=thirty&story=newton<br />
<br />
:'''2:''' https://www.newscientist.com/blogs/culturelab/2010/01/newtons-apple-the-real-story.html<br />
<br />
:'''3:''' http://www.physicsclassroom.com/class/newtlaws/Lesson-4/Newton-s-Third-Law<br />
<br />
:'''4:''' Matter and Interactions By Ruth W. Chabay, Bruce A. Sherwood - Chapter 3.4<br />
<br />
[[Category:Which Category did you place this in?]]</div>Nromer3