1. The problem statement, all variables and given/known data Determine the total electrostatic potential energy of a nonconducting sphere of radius r0 carrying a total charge Q distributed uniformly throughout its volume. Express your answer in terms of the variables Q, r0, and appropriate constants. 2. Relevant equations V = kQ/r U = qV 3. The attempt at a solution Since the total amount of charge within the sphere is Q and the sphere has a radius of r0, we can make V = kQ/r0. Since U = qV, then U = kqQ/r0. However, I'm not sure how to express q in terms of Q.