[SOLVED] Conservation of Energy 1. The problem statement, all variables and given/known data A proton (charge e, mass = 1.67 * 10^-27 kg) accelerates from rest by crossing a potential difference V = 3.00 V a.) Find the velocity v_0 it acquires? (Suppose this proton, having initial velocity v_0 from part (a), moves from very away directly towards a stationary heavy ion which is singly charged, i.e. having the same charge as the proton, +e.) b.) Find the distance r_min between the proton and the ion at the moment of closest approach? c.) Find velocity v of a proton when it is at a distance r = 2r_min from the ion 2. Relevant equations a = (q/m)E V = kQ/r V = E*d (parallel plate) 3. The attempt at a solution I am literally stuck for part a into determining what it could be, it seems something is missing in the problem. Please help. Thanks!