In a common physics demonstration, two identical carts having rigid metal surfaces and equal speeds collide with each other. Each cart has a piece of Velcro® at one end and a spring at the other end, as is shown in Figure 8.51. For each collision shown in the figure, find the magnitude and direction of the velocity of each cart after the collision. Are both collisions elastic? What causes one of them to be inelastic, and what happens to the “lost” kinetic energy?
Figure 8.51
Problem 70.
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