# Homework Help: Charge Density Expression

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1. Dec 8, 2018

### TishBass

1. The problem statement, all variables and given/known data
A charge Q is uniformly distributed throughout a nonconducting sphere of radius R. Write the expression of the charge density in the sphere?

2. Relevant equations
Charge density ρ=dQ/dV
Gauss's Law ∫EdA = E(4ϖr^2)

3. The attempt at a solution
If Q is uniform then ρ=Q/dV and the volume of a sphere is 4/3ϖr^3 then I think charge density would just be ρ=Q/(4/3ϖr^3).
This is suspiciously simple so I would just like external input on the problem. I have a feeling that I may need to use Gauss's Law somehow.

2. Dec 8, 2018

### PeroK

That's all there is to it. $Q$ could be anything uniformly distributed across volume $V$ and the density is, by definition, $Q/V$.