Two particles with mass m1 = 2.0 kg and m2 = 5.0 kg can slide on a frictionless rod. A spring with k = 1000 N/m is attached to m2. The velocity of the first ball is v1= 14 m/s and the second is at rest.
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a. What is the maximum compression of the spring when the particles collide?
b. What are the velocities of the particles after the collision?