Two protons that are very far apart are hurled straight at each other, each with an initial kinetic energy of 0.19 MeV, where 1 mega electron volt is equal to 1106 (1.610-19) joules. What is the separation of the protons from each other when they momentarily come to a stop?
separation = 1 m

Maybe I'm just missing the necessary formula. Is there a way to incorporate Electric Potential Energy formula and the energy principle here?