Question

a ball of mass 150g and velocity 12m/s coming towards a bats man is hit by him with a force of 480 N IN SUCH A WAY THAT the ball moves with velocity 20m/s in the direction opposite to its original one. find the time of contact between the ball and the bat

Answer 1

Mass of ball, m = 150 g = 0.15 kg
Initial velocity, u = 12 m/s
Final velocity, v = -20 m/s (Negative sign is due to change in direction)
Time, t = ?
Force exerted by ball on bat, F = -450 N (Negative sign is due to change in direction)
We know that,
F = ma
or, F = m(v - u)/t
or, -450 = 0.15(-20 - 12)/t
or, t = 0.011 s.