Electric Field and Potential in a conductor

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Discussion Overview

The discussion revolves around the behavior of electric fields and potentials within conductors, specifically addressing a scenario involving a uniformly charged spherical shell. Participants explore the apparent contradiction between textbook statements and problem-solving outcomes related to electric fields inside conductors versus insulating shells.

Discussion Character

  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant cites a textbook claim that the electric field inside a conductor must be zero, as free charges would move to cancel any existing field.
  • The same participant notes a problem that suggests a non-zero electric field inside a uniformly charged spherical shell, leading to confusion.
  • Another participant argues that a uniformly charged shell cannot be a conductor, highlighting the contradiction in the original claim.
  • A further inquiry questions whether the shell is indeed uniformly charged or if it might be a uniformly charged sphere or a thick shell, suggesting the need for clarification on the problem statement.
  • One participant recommends posting the exact wording of the question to facilitate better understanding and resolution of the confusion.

Areas of Agreement / Disagreement

Participants express disagreement regarding the nature of the shell in question and its implications for the electric field. There is no consensus on the resolution of the apparent contradiction between the textbook statement and the problem's requirements.

Contextual Notes

Participants note that the distinction between a uniformly charged shell and a uniformly charged sphere is crucial to understanding the electric field behavior, but the specific details of the problem remain unclear.

bubblewrap
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So in my textbook (Introduction to Electrodynamics by Griffiths) it said that inside a conductor, the electric field E would have to zero, since if it wasn't the free charges would move accordingly and create a electric field that cancels the original field. But in a question that soon followed, it asked me to find the potential and electric field inside a uniformly charged spherical shell. This, according to the answers, which was very straightforward; using Gauss's law to calculate the electric field and so on; produced a electric field that was NOT 0 inside the conductor, rather something that was proportional to the inverse of the distance between the point of interest and the center of the sphere. Now these two obviously contradict each other, so I'm very confused right now.

Any help would be greatly appreciated. Thanks
 
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bubblewrap said:
But in a question that soon followed, it asked me to find the potential and electric field inside a uniformly charged spherical shell.
If it is uniformly charged then it is not a conductor. The proof is the very contradiction you noticed.
 
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Are you sure that is a shell and not an uniformly charged sphere? Or maybe a thick shell? What problem is that?
The field inside an uniformly charged thin shell is zero no matter if it's conductive or insulating.
 
bubblewrap said:
But in a question that soon followed,

I recommend posting the exact question word for word.
 
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