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

A hockey ball of mass 200 g travelling at 10ms-1 is struck by a hocke

1.	A hockey ball of mass 200 g travelling at 10ms-1 is struck by a hockey stick so as to return it along its original path with a velocity at 5ms-1 Calculate the change of momentum occurred in the motion of the hockey ball by the force applied by the hockey stick.
Answer» Mass of hockey ball m = 200 g = 0.2 Kg Initial velocity u = 10ms^-1 Final velocity v = 5 ms^-1 (Since the momentum of the ball = Final momentum – initial momentum = mv – mu = m (v – u) = -0.2 (-5 – 10) = 0.2 × -15 = -3 Kgms^-1.