A hockey ball of mass 200 g travelling at 10 m `s^(-1)` is struck by a hockey stick so as to return it along its original path with a velocity at 5 m `s^(-1)`. Calculate the change of momentum occurred in the motion of the hockey ball by the force applied by the hockey stick.

Explanation

Initial momentum
` 0.2 xx 10 =2` kg m/s
Find momentum
` 0.2 xx -5`
` = -1` kg m/s
Change in momentum ` = -1 -2`
` = -3` kg m/s