help with my physics work..

Question

if a 1279kg car is moving at 26.82 m/s when is hits a truck, resulting in a 20,000N force that slows the car down to 10 m/s, how long did the car experience the force?

Answer 1

Impulse J = mΔv = FΔt

The car is hit by an impulse force over a certain amount of time, which is also equivalent to its mass and change in velocity. With this relationship, the impulse

J = 1279 kg * (10 - 26.82 m/s)

Δt = J / F

Δt = -21,512.78 kg m/s / -20,000 N = 1.08 seconds (Impulse time)

We say negative because the force is going in the negative direction, which accounts for the final minus initial velocity being negative as well.