Electric Field and Potential in a conductor

In summary: Based on the conversation, it seems that there is a contradiction between the concept of the electric field being zero inside a conductor and the calculation of the electric field inside a uniformly charged spherical shell. This could be due to the fact that the shell is not a perfect conductor and therefore, the electric field is not zero inside. It is important to clarify the exact question and context in order to fully understand the discrepancy.
  • #1
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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  • #2
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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  • #3
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.
 
  • #4
bubblewrap said:
But in a question that soon followed,

I recommend posting the exact question word for word.
 
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FAQ: Electric Field and Potential in a conductor

1. What is an electric field in a conductor?

An electric field in a conductor is a region in which electric charges experience a force. In a conductor, the electric field is created by the presence of other charges and is responsible for the movement of charges within the conductor.

2. How is the electric field related to the potential in a conductor?

The electric field and potential in a conductor are closely related. The potential in a conductor is a measure of the electric potential energy per unit charge, while the electric field is the force per unit charge. In a conductor, the electric field is directly proportional to the potential gradient.

3. Can an electric field exist inside a conductor?

No, an electric field cannot exist inside a conductor. This is because the free charges in a conductor will always move in such a way as to cancel out any electric field within the conductor. This is known as the Faraday cage effect.

4. How does the shape of a conductor affect the electric field and potential?

The shape of a conductor can have a significant impact on the electric field and potential within it. The electric field is strongest at sharp points and is weaker at rounded edges. The potential is also higher at sharp points and decreases as the distance from the point increases.

5. What is the difference between an electric field in a conductor and an insulator?

The main difference between an electric field in a conductor and an insulator is that in a conductor, the electric field is distributed evenly throughout the material, while in an insulator, the electric field is concentrated near the surface of the material. This is because conductors allow for the free movement of charges, while insulators do not.

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