Bound and Free Charge in conductor and dielectric

AI Thread Summary
The discussion focuses on understanding the concepts of bound and free charge in conductors and dielectrics. Free charges can move freely in response to external forces, while bound charges are confined to small movements around their respective atoms or molecules. A user seeks clarification on the relationship between bound and free charges, particularly in the context of a wire with an insulating dielectric. They mention using Gauss's law to derive the equality of bound charges on the surfaces of the insulator but struggle with the concept of enclosed free charge. The conversation emphasizes the importance of grasping these fundamental electrostatic principles for better comprehension.
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I am reading an electrodynamics book to grasp the concept of bound and free charge, esp in conductor and dielectric. I got lost with the text on the book. Can anyone please help me understand the concept well?
 
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I bet some people here could help... what specific questions do you have?
 
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A free charge can move in response to an externally supplied force while a bound charge cannot.
 
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Free charges are free to move about the entire medium, while bound charges are restricted to moving in small 'loops' around whichever molecule/ atom they are bound to.
 
gabbagabbahey said:
Free charges are free to move about the entire medium, while bound charges are restricted to moving in small 'loops' around whichever molecule/ atom they are bound to.

For a bit more detail, click free charge for the PF Library item :smile:
 
thanks

in case of a wire carrying a certain amount of charge, say Q, which is insulated by a insulator (dielectric), I read that the bound charge on the outer surface and inner surface of the insulator is equal to each other in magnitude. But I could not derive it myself. My approach was to use Guass's law for D, but i did not get what enclosed free charge was. In such a case, how does the equation \rho = \rhob + \rhof hold true?
 
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