Total Charge (Spheres and Potential)

jrc5135
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Homework Statement


A conducting sphere of radius a, at potential V0, is surrounded by a thin concentric spherical shell of radius b over which someone has glued a surface charge. sigma = kcos(theta) where k is a constant

i know V(r, theta) and induced surface charge on the conductor


Homework Equations



Q = integral (sigma) da

The Attempt at a Solution


trying to use equation 1 but I'm not sure first off the limits on r for each
 
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da is the infinitesimal area element of the surface...the entire surface is at r=b...what is your expression for da?
 
but what about the charge coming from the inner sphere at Vo my da is going to rdrdtheta
 
why is there a dr term in your da, isn't r constant over a spherical surface?

Are you trying to compute the total charge on the outer shell, or the conductor, or both?
 
trying to find the charge for both
 
Well, you'll have to compute the charge of each individually and then add them up.
 

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