Adefensive stroke where the ball is struck with a downward and forward motion with a short chopping motion

Back spin

Explanation:

A defensive stroke where the ball is struck with a downward and forward motion with a short chopping motion is called Back spin.Backspin is opposite to topspin. Direction of spin imparts and upward force that lift the ball, While a standard strike bounces far forward as up, backspin shots bounce upwards and downwards.

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the tires are rotating at 0.434 rpmlinear speed=45 m/sdiameter=0.550 mradius=0.275 mnow v= rωω= v/rω=45/0.275ω=163.6 rad/sω=163.6 rad/s (1rev/2π rad) (60s/1m)ω=1563 rpm