Question

1. A 59 kg person is in a vehicle travelling at 41 m/s. The vehicle runs into a telephone pole. At impact, it

takes the vehicle 192 milliseconds to come to a stop.
a. What is the average force exerted on the person?
b. Some people think they can stop their bodies from lurching forward in a vehicle by putting their
hands on the dashboard. Find the mass of an object that has a weight equal to the force you just
calculated. Could you lift such a mass? Are you strong enough to stop your body with your arms?

Answer 1

a. 12,600 N

b. 1290 kg

Step-by-step explanation:

a. Impulse = change in momentum

F Δt = m Δv

F (0.192 s) = (59 kg) (0 m/s − 41 m/s)

F = -12,600 N

b. F = mg

12,600 N = m (9.8 m/s²)

m = 1290 kg (or 2,830 lbs)