Dynamic properties of tennis balls
نویسنده
چکیده
Measurements are presented on the dynamic properties of several different tennis balls, during impacts on a force plate. The force on a tennis ball rises rapidly to about half its maximum value in the ®rst 200 ls of the impact due to compression of the cloth cover and the rubber wall near the impact point. The wall then collapses inwards, resulting in a sudden decrease in ball stiffness. Results are presented on the force waveform, the impact duration, ball compression and coef®cient of restitution as a function of ball speed.
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