- #1
EricVT
- 166
- 6
Homework Statement
An electric field in the region r > a is given by
E,r = 2*A*cos(theda)/r^3
E,theda = A*sin(theda)/r^3
E,phi = 0
A = constant
Find the volume charge density in this region.
E,r and E,theda and E,phi are the components of E in the r, theda, and phi directions, respectively.
Homework Equations
div E = p/eo
p = volume charge density
E = electric field
eo = permittivity of free space
div is divergence
The Attempt at a Solution
Well, I started by calculating the divergence of E in spherical coordinates and got that it is equal to zero. So p/eo = 0 ==> p = 0?
This isn't correct, so I'm confused on what I need to do. Does r > a have some significance? It gives no information about what sort of volume this is or what a is, and there are no diagrams or anything.
Thanks for any help.