Hurling protons at one another to find where they stop

[HellaciousD]

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 (1*10^6)*(1.6*10^-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?

 

[willem2]

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 (1*10^6)*(1.6*10^-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?

Certainly. The protons will stop when all their kinetic energy is converted to electric potential energy.
Both of the protons have kinetic energy at the start. The potential energy $$\frac {k q_1 q_2} {r}$$ is shared by both protons.