Two perfectly elastic small smooth spheres A and B have masses 3m and m respectively. They lie at rest on a smooth horizontal plane with B at a distance a from a smooth vertical barrier. The line of centres of the spheres is perpendicular to the barrier, and B is between A and the barrier (see diagram). Sphere A is projected towards sphere B with speed 11 and, after the collision between the spheres, B hits the barrier. The coefficient of restitution between B and the barrier is 1/2. Find the speeds of A and B immediately after they first collide, and the distance from the barrier of the point where they collide for the second time. 

Transcribed Image Text:

3m B