Potential of a spherical shell (non-uniform charge density)

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SquidgyGuff
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Homework Statement


Given a spherical shell of radius R and the surface charge density
gif.gif
(
gif.gif
being the angle from the top of the sphere
gif.gif
and
gif.gif
being a constant) find the electric potential
gif.gif
and the electric field
gif.gif
inside and outside the sphere. Check that both the potential is continuous inside and outside the sphere and that
gif.gif
inside and out. I made this little diagram to illustrate.
sphere_by_k4l3b-d98wxw3.png


2. Homework Equations

gif.gif

gif.gif


The Attempt at a Solution


I can't even understand this problem. I feel like the point of interest shown in the diagram should be on the shell so that
gif.gif
can return a meaningful value, but I need to find the potential and electric field everywhere, so it can't be on the sphere.
 
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Hello Guff,

I notice that your problem statement mentions a charge distribution on the surface of the sphere, but that there is no equation where charge or charge density plays a role. Is there something you can add to your 'toolbox' ?
 
BvU said:
Hello Guff,

I notice that your problem statement mentions a charge distribution on the surface of the sphere, but that there is no equation where charge or charge density plays a role. Is there something you can add to your 'toolbox' ?
If I looked at the charge distribution a point charge the field would look like this
%5Cfrac%7B%28%5Csigma_%7B0%7Dcos%5Ctheta%29%284%5Cpi%20R%5E%7B2%7D%29%7D%7Br%5E2%7D%5Chat%7Br%7D.gif
, but I know that isn't correct because I believe the total charge is zero. because half of the values of
gif.gif
are negative and the other half are positive.