Question

a cricket ball of mass 150 gram moving at 36 M per second strikes a back and returns back along the same lines at 21 m per second what is the change in momentum produced if that reminds in contact with the ball for 1 \ 20 seconds what is the average force exerted in Newton

Answer 1

Mass of the ball, m = 150 g = 0.15 kg

Initial speed of the ball, u = -36 m/s( it is taken as negative because one is going and other coming so inorder to accompany direction also)

Final speed of the bal after being hit, v = 21m/s

Impulse = change in momentum = final momentum - initial momentum

= Impulse = 0.15 × (21--36) = 0.15*57 = 8.55 Ns

force = impulse/time
=8.55/(1/20)
=8.55*20
=171 N