Charge Transfer: Difference between revisions

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==Transfer Charges by Induction==
==Transfer Charges by Induction==


induction is the movement of electrons to one part of an object that is caused by the electric field of a second object. the electric field around the charged object attracts or repels electrons in the second object. polarizes
Unlike the transfer of charges by conduction, objects that becomes charged to each other do not require points of contact. When an object is charged, it has an electric field. This electric field will repel or attract electrons in another object. This electron movement is called transfer of charges by induction. A neutral object can be charged by another charged object through a process called '''polarization'''. This is when electrons in the object is repelled or attracted to one side of the object by the charged second object. For example, if a negatively charged sphere is placed near a neutral sphere, the electrons in the neutral sphere will be repelled by the charged sphere. The neutral sphere is now polarized, with one side of it being negatively charged and the other side being positively charged. The negatively charged side of the sphere can be removed through grounding or with a conductor. Once removed, the originally neutral sphere will now be positively charged. Another example of induction is the balloon and black pepper experiment. A balloon can be given a negative charge by rubbing it on hair. When the balloon is placed near grounded black pepper, the black pepper particles will be polarized so that it becomes positively charged on top and will be attracted to the negatively charged balloon.  
give neutral object a charge by moving a charged object near it, then grounding or taking away the other charge with hand or conductor, and then remove both so that resulting object is charged
example is rubbing balloon on hair to get negative charge, then put balloon close to black pepper, the black pepper particles will jump up and stick to the balloon because the particles were polarized so that it becomes positively charged on top and will be attracted the negatively charged balloon. electrons on the bottom of the black pepper will be grounded into the surface its sitting on, so that the black pepper particles become psotively charged.


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Revision as of 20:52, 5 December 2015

claimed by Lzhang375

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

Insulators vs Conductors

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

Charges transferred to an insulator remains at the location of transfer.

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

Transfer Charges by Conduction

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

Transfer Charges by Induction

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

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See also

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

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

Further reading

Books, Articles or other print media on this topic

External links

Internet resources on this topic:

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

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

References

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