Gauss' Law Hollow Sphere with Charged Ball

AI Thread Summary
The discussion focuses on applying Gauss' Law to determine the electric field strength in various regions around a uniformly charged ball and a hollow metal shell. For r < a, the electric field is based solely on the charge of the ball, while for a < r < b, the electric field is zero since there is no net charge in the hollow region. In the range b < r < c, the electric field is influenced by the charge on the outer shell, and the same principles apply as with conductors. For r > c, the total charge enclosed, which includes both the hollow sphere and the ball, dictates the outward electric field. Clarifications on flux concepts and charge distribution are essential for understanding the electric field behavior in these scenarios.
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Homework Statement


A uniformly charged ball of radius a and charge -Q is at the center of a hollow metal shell with inner raduis b and outer radius c. \The hollow sphere has net charge +2Q.

Determine the Electric Field Strength at r when r is,

r < a
a < r < b
b< r < c
r > c


Homework Equations


I'm struggling with the flux concepts in this case.


The Attempt at a Solution


I guess the main concepts I need clarification on is:
in the hollow sphere, there is flux pointing out from the metal spherical surface, but is there flux pointing into the hollow sphere? (in that case would there be a net flux into the small ball?)
Inside the actual shell of a charged metal sphere ( or inside a charged slab/puck/etc.), what is the flux, is it 0?



Here's my analysis for the problem

So when r < a , the net flux at r only depends on the charge inside the small ball.

When a < r < b, ok so this is where I'm struggling, please tell me if my analysis is wrong,
r is the hollow part, since all the charge gathers on the surface, r has no net charge, so it has no net flux, so its E field is 0?

when b < r < c, this is IN the shell of the charged outer sphere, now I know how to deal with the flux at the surfaces of conductors, so would this be the same thing?

when r > c, this is at a point outside the large sphere, so the flux is related to the net charge of the sphere and the ball
 
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first of all, flux depends on total charge enclosed. So total charge of hollow sphere + ball = Q. So net flux is outwards.

for r<a, use uniformity of charge on ball, by finding charge density.
 
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