Particle `A` having positive charges is moving directly head -on to wards initially stationary positively charged particle ` B`. At the instant when `A` and `B` are closest together .

Options

A. the momenta of A and B must be equal
B. the velocities of A and B must be equal
C. B would have gained less kinetic energy than A would have lost.
D. B would have gained the same momentum as A would have lost.

Answer

B, C, D