- #1
an_single_egg
- 10
- 0
Homework Statement
A nonconducting sphere of radius r0 carries a total charge Q. The charge density ρE increases as the square of the distance from the center of the sphere, and ρE=0 at the center.
a) Determine the electric potential as a function of the distance r from the center of the sphere for r > r0. Take V=0 for r=∞.
b) Determine the electric potential as a function of the distance r from the center of the sphere for r < r0.
Homework Equations
[/B]
Vb-Va = -∫E⋅dl
The Attempt at a Solution
[/B]
a) Because it is a sphere with total charge Q,
E=kQ/r2
From ∞ to r,
-∫kQ/r2 dr
=-kQ * [-1/r](∞→r)
= kQ/r
Part a I think I understand OK.
b) I don't know where to begin here really. Because r<r0, I can't use E=kQ/r^2.
The question (I think) is saying that Q isn't distributed evenly.
So would ρE = dQ/dV?
How do I find E with a changing charge AND changing radius?
Let me know if any of my formatting is weird, this is only my second time trying to post something.