How Do You Calculate Charge Density in a Uniform Sphere?

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To calculate the charge density in a uniform sphere, the charge density ρ is defined as ρ = Q/V, where Q is the total charge and V is the volume of the sphere. The volume of a sphere is given by V = (4/3)πr³, leading to the expression ρ = Q/(4/3)πr³. This calculation assumes that the charge is uniformly distributed throughout the sphere. The discussion also suggests that Gauss's Law may be relevant for further analysis, although the basic formula for charge density is straightforward. Understanding these principles is essential for solving related physics problems.
TishBass
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Homework Statement


A charge Q is uniformly distributed throughout a nonconducting sphere of radius R. Write the expression of the charge density in the sphere?

Homework Equations


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

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.
 
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TishBass said:

Homework Statement


A charge Q is uniformly distributed throughout a nonconducting sphere of radius R. Write the expression of the charge density in the sphere?

Homework Equations


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

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.

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