Say you have a spherical conductor of radius a located inside the cavity of a larger spherical conductor of radius b, and that the larger sphere's outer radius is c(adsbygoogle = window.adsbygoogle || []).push({});

If you charge the inner conductor at a to a charge Q, the inside part of the outer conductor becomes charged -Q and the outer outer part with Q again, ok, I got that

then it wanted the potential anywhere. I understand the potential outside the whole thing, the potential between b and c, but when r is from a to b I had trouble. I had the answer beforehand, which is kQ/(rbc)*[bc-r(b-c)] or I may've mixed that up

I see that if you unsimplify that it's like a sum of potentials. It's the potential between a and b, kQ/r, minus the potential AT the surface b(well, the Q is negative there so I guess you can just say plus the potential at b)plus the potential at c

Simple question: Why is it like that? Is there a more systematic way of reaching that answer? oh and of course the answer from a to b is like that one with r=a

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# Homework Help: Question involving potentials and spherical conductors/capacitors/things

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