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shinobi20
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Homework Statement
A sphere with radius R has a spherically symmetric charge density that varies as 1/r. What is the electric field outside and inside the sphere?
Homework Equations
E=kQ/r^2, ε=permitivity of free space, Q=total charge, ρ=charge density, dτ=infinitesimal volume
The Attempt at a Solution
For the case (outside), due to the concept that we can treat the sphere as a point charge, E = (1/4*pi*e)(Q/r^2).
For the case (inside), by using a Gaussian surface, we have E (4πr^2) = Q/ε. By evaluating Q = ∫ ρ dτ. I got E = (R^2)/(2εr^2).
Is this correct? Or am I missing something?
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