# Hey! Why did you collide when I was resting?

Particle A and B lie along same straight line. Mass of particle A is $$2.5$$ kg and of B is $$22.5$$ kg. Particle A is travelling with intial velocity u = $$375$$ m/s while B is at rest. Then after sometime they both collide head on elastically. The total linear momentum of system is conserved. Then find the velocity of particle B after collision in m/s .

×