Question

A cricket ball of mass 0.15 kg is moving with a velocity of 12 ms^-1 and is hit by a bat so that the ball is turned back with a velocity of 20 ms^-1. If the force of blow acts for 0.01 s, find the average force exerted on the ball by the bat.

Answer 1

Initial velocity u = 12 ms^-1

Final velocity v = 20 ms^-1

Change in velocity = 20 – (- 12)

= 20 + 12

= 32 ms^-1

(-ve sign is taken because initial and final velocities are in opposite direction)

Time for which force is acting, t = 0.01 s

∴ acceleration a = (change in velocity/time)

= 32/0.01

= 3200 ms^-2

Force F = ma

= 0.15 × 3200

= 480 N.