Compute all parts of given question:
Question: A railroad car of mass 2.6 104 kg moving at 5.00 m/s collides and couples with two coupled railroad cars, each of the same mass as the single car and moving in the same direction at 1.20 m/s.
Part A: What is the speed of the three coupled cars after the collision?
Part B: How much kinetic energy is lost in the collision?
I need help to determine the speed of the three coupled cars after the collision.