1. how fast would a 0.25 kg football have to be traveling to have the same momentum as a 0.05 kg bullet travelling 500 m/s?
2. sarah, who has a mass of 55 kg, is riding in a car at 20 m/s. she sees a cat crossing the street and slams on the brakes! her seatbelt stops her from flying forward, bringing her to rest in 0.5 seconds. how much force did the seatbelt put on sarah?
3. a big league hitter attacks a fastball! the ball has a mass of 0.16 kg. it is pitched at 38 m/s. after the player hits the ball, it is now traveling 44 m/s in the opposite direction. the impact lasted 0.002 seconds. how big of a force did the ballplayer put on that ball?