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When you drop a tennis ball, it hits the floor and bounces back up. But, it does not reach the same height as before and each time bounce is smaller than the previous one. However, you notice the tennis ball is slightly warmer after it finishes bouncing. Explain how the law of conservation of energy is obeyed.
What is During each bounce, some of the kinetic energy of the ball in transfered into thermal energy. As a result, energy is not created or destroyed, but only changes form so that the law of conservation of energy is obeyed.