explain why a cricketer moves his hands backwards while catching a fast moving cricket ball.
A cricketer moves his hand backwards because by doing this he increses the time due to which the rate of change of momentum decreases. That means that the ball comes to rest gently and does not hurt the fielder. But, if does not move his hand backwards, then the ball would come to rest in a fraction of a second with a high rate of change of momentum. The ball will exert a lot of force on the hands of the fielder which will hurt him