Consider a sphere with uniform charge density , and radius R. A small circular p
ID: 1706258 • Letter: C
Question
Consider a sphere with uniform charge density , and radius R. A small circular piece with radius ra is removed from the sphere. Find the potential at the centre of the opening in the sphere.
I think I understand how to find the potential of a standard sphere at some point. But I'm confused as to if this is just a spherical shell, and there is a circular hole in it. Which, from gauss's law, I was under the impression that the potential would be zero at the center of the hole, because there is no charge enclosed? But that just doesn't seem like a reasonable answer. So then I thought it might be a full sphere, with a circular tube cut out of it, but again, it doesn't say how deep, so I doubt that works.
I'm just confused as to how I should approach this!
Explanation / Answer
It would have been great if you posted a picture. I wonder why it's a surface density while it would be more reasonable if it was volume density (ro - ). The approch to solving this problem is by substituting the charge Q with A and not forgetting to subtract the A' for the little piece. Hope this helps :)