Does an electric field go through a conductor ?

  • Thread starter jaredvert
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I know there is no net flux in a conductor but do they go through the conductor? Say you have a positive q charge inside a hollow sphere that's charged pos q as well. Well that charge from the inner shell should keep penetrating space until it hits a negative charge which implies it goes through the conductor meaning the electric field in a conductor isn't zero. Just that the same number in go out as well. Am I correct? Thanks
 

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  • #2
Nugatory
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I know there is no net flux in a conductor but do they go through the conductor? Say you have a positive q charge inside a hollow sphere that's charged pos q as well. Well that charge from the inner shell should keep penetrating space until it hits a negative charge which implies it goes through the conductor meaning the electric field in a conductor isn't zero. Just that the same number in go out as well. Am I correct?

No. What happens is that the negative charges in the conductor are attracted by the electrical field of the positive charge in the center, so they move to the inside surface of the shell (it's a conductor, so they can move around freely within it). That leaves the outside surface of the shell with a net positive charge.

We end up with the positive charge in the center generating an electric field throughout the interior of the shell; this field is stopped cold at the inner surface of the shell where negative charges have piled up to cancel it; then no field at all between the inner and outer surfaces of the shell; then the positive charge on the outer surface of the shell filling the entire universe outside the shell with an electrical field.

The only way you could tell the difference between what actually happens (field stops at the inner surface of the shell and starts up again at the outer surface) and what you describe (field passes through the conductive shell, same out as in) is by measuring the field between the inner and outer surfaces of the shell.. This has been done, and it comes out zero.
 
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I understood the original question differently.
What if we have a +q charge inside the shell, but the shell on its own also has a +q charge?
Would the inside charge also attract electrons leaving the outside of the shell still more positive?
Then there would still be no field inside the conductor but outside we would measure a +2q charge, right?
 
  • #4
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I understood the original question differently.
What if we have a +q charge inside the shell, but the shell on its own also has a +q charge?
Would the inside charge also attract electrons leaving the outside of the shell still more positive?
Then there would still be no field inside the conductor but outside we would measure a +2q charge, right?

Right. And in the hollow interior of the shell we'd just see the field from the single +q in the center.
 

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