13. A hockey ball of mass 200 g travelling at 10 ms–1 is struck by a

1.	13. A hockey ball of mass 200 g travelling at 10 ms–1 is struck by a hockey stick so as to return it along its original path with a velocity at 5 ms–1. Calculate the magnitude of change of momentum occurred in the motion of the hockey ball by the force applied by the hockey stick.
Answer» ANSWER: CHANGE in MOMENTUM= ∆ (mv) or m∆v and since velocity changes it direction therefore ∆ v = V2 - V1 ∆ v = V2 - (- V1) ∆ v = V2+ V1 ∆ v = 15 therefore change in momentum= 0.2(kg) × 15 which is equal to 3 kg m/s

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

Answer»

or m∆v

and since velocity changes it direction

therefore

∆ v = V2 - V1

∆ v = V2 - (- V1)

∆ v = V2+ V1

∆ v = 15

therefore

change in momentum= 0.2(kg) × 15

which is equal to 3 kg m/s