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jg370
jg370 said:I have an thin, hollow, non-conducting sphere with charge[tex]\sigma[/tex]. The magnitude of the electric field at the surface is [tex] \sigma[/tex]/[tex]\epsilon[/tex].
I am asked to show that if a tiny hole is made through the sphere, then the magnitude of the electric field in the hole is [tex] \sigma[/tex]/[tex]2\epsilon[/tex].
Here is my trial solution:
When a hole is made in the sphere, we no longer have a close surface. To find the magnitude of the electric field in the hole, let's imagine that we place a "plug" in the hole; then we have a closed surface and,
[tex]\int(sphere) E dS - \int(plug) E dS = \sigma/\epsilon[/tex].
However, this is not getting me the solution sought.
So, after thinking about this some more, I am wordering what happens to the charge on the sphere when a hole is made in it. The sphere is no longer a closed surface. Does the charge redistribute itself on the outside and inside?
However, the sphere is non-conducting, so there will not be any redistribution of charge. The only thing I can think of is that the field in the hole must be provided by the material near the hole.
Any comments that could help solve this problem?
Tks, JG