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When a person throw a tennis ball in downward direction towards the surface with an anti-clock rotation, then when it comes up after striking to the surface the rotation is reversed. Why is that?

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    $\begingroup$ Really? You can do this? I tried bouncing a few tennis ball an I observed the rate of rotation was decreased but the direction was not reversed. $\endgroup$
    – M. Enns
    Apr 28, 2017 at 15:05

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Assume the contact area has a high friction and the ball is not sliding at the contact point. What is however still rotating is the remaining part of the ball (since it is not rigid), however not forever: Tension is increasing (like contracting a spring on one side of the ball and stretching on the other). At some point the contraction and stretching of the ball -- due to its initial rotation -- comes to a halt and the process reverses. Therefore, the reflected ball spins in the opposite direction.

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  • $\begingroup$ Exactly what i speculated. Thanks for the answer. $\endgroup$
    – Deiknymi
    Apr 28, 2017 at 15:29

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