# Homework Help: The electric potential of 2 hollow concentric spherical shells

1. Jan 26, 2010

### Figigaly

1. The problem statement, all variables and given/known data
Consider two concentric conductive hollow spherical shells. The inner shell has radius R1 and holds the charge +q. The outer shell has charge R2 and holds charge -q. Determine an expression for the potential difference between the shells.

2. Relevant equations

V = q / (4 pi ε0 r) when r greater or equal to the radius of the shell

V = q / (4 pi ε0 R) when r is less than the radius (R) of the shell

3. The attempt at a solution

I said due to fact that electric potential has superposition principle. The total electric potential between the shells:
therefore: V = q / (4 pi ε0) (1/r - 1/R2)
I am unsure if this is true or not any help would be appreciated, Thanks

2. Jan 26, 2010

### ideasrule

Yup, looks right to me.