Question

a fielder pulls his hands gradually with the moving ball while holding a catch. Why?

Answer 1

by increasing the impulsive time effect of impulse decreases

Answer 2

By the 2nd law of Newton, the rate of change momentum is directly proportional to the force. Thus the fielder pulls his hand back to reduce the time in which the velocity of fast ball reduces to 0. This increases the time reducing the rate of change of momentum, n thus reduces the force in the fielders palm. This his hand doesn't hurt