1. The problem statement, all variables and given/known data In a model for the hydrogen atom, an electron is in circular orbit at mean distance Ro from the nucleus. Sketch U as a function of seperation distance r. Write an algebraic expression for the electric potential energy U for a model of this system, i.e. charges +e and -e seperated by distance Ro. Be sure to state the reference you have used for zero potential energy. The attempt at a solution The only relevant (?) formula I could find is this one: V=q/(4pi*εo*r) How I can sketch the function or write the algebraic expression from that is beyond me though..