일반물리학 1 — Center of Mass and Linear Momentum: Problem 65

65 Particle 1 with mass m and velocity v and particle 2 with mass 2m and velocity -2v are moving toward each other along an x axis when they undergo a one-dimensional elastic collision. After the collision, what are the velocities of (a) particle 1 and (b) particle 2? What is the velocity of the center of mass of the two-particle system (c) before and (d) after the collision?