Why does the tennis ball bounce best on a tennis racquet?

Answer 1

A tennis ball, when impacted, dissipates about 45% of the energy applied to it. This means that it only absorbs and returns 55% of that energy. That is why in the test standard for tennis balls, dropping it from 100 inches, it only rebounds 53 to 58 inches. It is returning that much energy. The strings of the racket, however, return 90% of the energy they are impacted with. So, when the tennis ball hits the strings and they stretch (absorb the energy), they will return 90% of that force in the return of the ball. When a ball hits strings with a higher tension, the force is exerted on the ball, instead of the strings, and the energy return is closer to the 55% range.