Concept explainers
Tennis Ball Testing
A tennis ball bouncing on a hard surface compresses and then rebounds. The details of the rebound are specified in tennis regulations. Tennis balls, to be acceptable for tournament play, must have a mass of 57.5 g. When dropped from a height of 2.5 m onto a concrete surface, a ball must rebound to a height of 1.4 m. During impact, the ball compresses by approximately 6 mm.
81. How fast is the ball moving when it hits the concrete surface? (Ignore air resistance.)
A. 5 m/s
B. 7 m/s
C. 25 m/s
D. 50 m/s
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