Question

In a perfectly inelastic one-dimensional collision between two moving objects, what condition alone is necessary so that the final kinetic energy of the system is zero after the collision?

(a) The objects must have initial momenta with the same magnitude but opposite directions.

(b) The objects must have the same mass.

(c) The objects must have the same initial velocity. 

(d) The objects must have the same initial speed, with velocity vectors in opposite direction.