Why Does Charge Only Distribute on the Outer Surface of a Conducting Shell?

AI Thread Summary
Excess charge on a conducting shell only resides on the outer surface due to the principles of electrostatics, specifically Gauss's Law. When charge is placed on the inner surface, the mutual repulsion among charged particles creates a net outward force, pushing them to the outer surface. The inner surface experiences no electric field from the uniformly charged outer surface, which prevents charge from accumulating there. Thus, the inner surface cannot support a stable charge distribution without an external electric field. Ultimately, the behavior of charges in a conductor leads to the conclusion that all excess charge must reside on the outer surface.
pixel
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It’s been a long time since I took E&M courses and even thought about these things, but a current thread has led me to question the location of excess charge on a conducting shell. Given that there are two surfaces to which charge can move, why doesn’t some charge also locate on the inner surface? Other than that it is on the outside, what makes the outer surface different from the inner surface as far as determining where charge locates?

I know from Gauss’s Law that the charge must be on the outer surface. I’m just looking for a physical/intuitive reason, hence the B prefix on this thread.
 
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Intuitive reason? Imagine that we were to place charged particles on the inner surface in such a way that there was a uniform charge density on the inner surface. The charged particles would all be repelling one another, so they would experience a net outwards force... And that pushes them to the outer surface.
 
Nugatory said:
Intuitive reason? Imagine that we were to place charged particles on the inner surface in such a way that there was a uniform charge density on the inner surface. The charged particles would all be repelling one another, so they would experience a net outwards force... And that pushes them to the outer surface.

Yes, so charge can't just be on inner surface. But couldn't we still consider charge on both the inner and outer surfaces such that the mutual repulsion was keeping them separated?
 
pixel said:
But couldn't we still consider charge on both the inner and outer surfaces such that the mutual repulsion was keeping them separated?
You won't get any repulsion unless there is a non-zero electrical field. All points on the interior surface are inside of the uniform spherical distribution of charge on the exterior surface. What is the electrical field inside of a uniform spherical charge distribution?
 
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