1. The problem statement, all variables and given/known data I want to derive the following equation. It is the potential energy of an electron inside a nucleus assumed to be a uniformly charged sphere of R. 2. Relevant equations V'(r) =( -Ze2/4∏ε0R)(3/2 - (1/2)(r/R)^2) 3. The attempt at a solution I get E = Ze2r/(4∏ε0R3) But I am having problem in integration limits and hence going towards final required result!