[QUE/EM-04006] --- EM-PROBLEM --- Potential of a conducting disk

Show that the potential due to a conducting disk of radius \(a\) and charge \(q\) is \begin{equation}  \phi(r,z) = \frac{q}{4\pi\epsilon_0 a}\int_0^\infty e^{-k|z|} J_0(kr)  \frac{\sin ka }{k}\, dk \end{equation}