# Electric Flux on the surface of a sphere

1. Apr 23, 2013

### NWNINA

1. The problem statement, all variables and given/known data

I'm trying to figure out an equation for finding the net flux that abandons the surface of a sphere which contains a line charge distribution an a charge density. The problem is:

A line charge distribution of 0.6m long with a charge density equal to 5C/m, is contained inside a sphere with radius of 5m. Find the net flux that abandons the surface of the sphere.

2. Relevant equations

What I have done is the following
ψ=DA
D= εE
ψ=εEA=ε(ρ/(2∏εr)(4∏r^2)
∴ψ =2 ρ r

3. The attempt at a solution

ψ= 2(5C/m)(5m) = 50C

I really don't know if this is the correct approach. Any help would be great.

Last edited by a moderator: Apr 24, 2013
2. Apr 23, 2013

### NWNINA

So I've decided to take a different approach
ψ= ∫∫∫ ρ rdrd∅dθ
not sure if i should use d∅ or dz. maybe the first one because it is spherical.
what limits should I use?

3. Apr 23, 2013

### SammyS

Staff Emeritus
Use Gauss's Law.

Calculating the flux directly by means of a surface integral will be a mess.