Question

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 frpm flying forward, bringing her to rest in 0.5 seconds. how much force did the seatbelt put on sarah?

Answer 1

You have to find the acceleration first. so you would use the equation a=Vf-V0/t.
This would be 0-20/0.5 which equals to be a=-40. then you plug this in to the force equation wich is F=ma. F=55 x -40.  F= -2200

Hope this helps!