This is a past paper question from FM Mechanics. It's been an hour and I cannot figure out a solution to this question:
Particles of masses m1 and m2 lie at rest on a smooth horizontal plane. Each particle is given a horizontal impulse of magnitude I towards the other particle so that the particles collide directly. Given that the collision is perfectly elastic, find the speeds of the particles after the collision.
Spoilers ahead! - The velocity (answer) of each particle is given in terms of the respective mass of the particle.