Question

A ball of mass 100g approaching a tennis player with a velocity of 10m/s, is hit back in the opposite direction with a velocity of 15m/s. If the time of impact between the racket and the ball is 0.01s. calculate the magnitude of the force with which the ball is hit.

Answer 1

Force = rate of change of momentum = change of momentum / time
change of momentum = 0.100 kg * (15 - -10) = .1*25 = 2.5 kg m/s
change of momentum / time = 2.5 kg m /s / 0.01 s = 250 kg m /s^2 = 250 Newtons