Question

A hockey ball of mass 200g travelling at 10m/s is struck by a hockey stick so as to return it along its original path with a velocity at m/s.Calculate the change of linear momentum occurred in the motion of the hockey ball by the force applied by the hockey stick.

Answer 1

Mass of the hockey ball, m = 200 g = 0.2 kg

Hockey ball travels with velocity, v1 = 10 m/s

Initial momentum = mv1

Hockey ball travels in the opposite direction with velocity, v2 = ˆ’5 m/s

Final momentum = mv2

Change in momentum = mv1 ˆ’ mv2 = 0.2 [10 ˆ’ (ˆ’5)] = 0.2 (15) = 3 kg m sˆ’1

Hence, the change in momentum of the hockey ball is 3 kg m sˆ’1.