What is the Charge Distribution on Concentric Spherical Shells?

[veronicak5678]

Homework Statement

You have two concentric conducting sherical shells. the net charge in the inner shell is -8 C and the outer shell is neutral. In the inner hollow is placed a 2C point charge. Using Gauss's Law, find the charge on all 4 surfaces of the shells.

Homework Equations

Econductor = 0

The Attempt at a Solution

Inner radius of inner shell: -2C
Outer radius of inner shell: -6C
Inner radius of outer shell: 0
Outer radius of outer shell: 0

Not sure how to use Gauss's law here, or if the answers for the outer shell are right.

 

[ideasrule]

Try envisioning a Gaussian sphere that lies outside the inner radius of the inner sphere but inside the outer radius. Do the same for the outer sphere.

 

[veronicak5678]

I think this means the inner shell answers are correct, but not the outer. Is the outer shell going to have a -8 charge on the inner radius and a positive 8 charge on the outer?

 

[ideasrule]

Not -8. Think about how much charge there is inside the outer shell.

 

[veronicak5678]

Oh! There is -6C inside the outer shell. So 6C on the inner and -6 on the outer.