Question

A 75-kilogram hockey player is skating across the

ice at a speed of 6.0 meters per second. What is
the magnitude of the average force required to
stop the player in 0.65 second?
(1) 120 N (3) 690 N
(2) 290 N (4) 920 N

Answer 1

I think it is (3) 690 N. You can use the theorem of Impulse and momentum where the impulse is equal to the change in momentum or:

`F \Delta t=m v_(f)-m v_(i)` (where f is for final and i for initial).
So you get:

`F*0.65=0-(75*6)`

`F=692 N`