## Divergence Theorem on a Cylinder

Can someone help me with how to do the following:

A thin column of radius $a$ and charge density $\rho_c$ surronds the $z$ axis

$\rho_c(R) = \{\begin{array}{cc}\rho_{0},&
R\leq a\\0, & R>a\end{array}$

(a) In cylindrical coordinates the electric field is $\underline{E} = E_R(R)\underline{{e_R}}$. Apply the divergence theorem to a cylinder of radius $R > a$ amd of UNIT length in $z$ to demonstrate that

${E_R}(R) = \frac{\rho_0a^2}{2\epsilon_0R}$
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I know that $\nabla \cdot E = \frac{\rho_c}{\epsilon}$

and I know the divergence theorem but I can't figure out how to do this

- Jason