Location Transport

Impluse and momentum change?

The National Transportation Safety Board is testing the crash-worthiness of a new car. The 2300 kg vehicle, moving at 15 m/s, is allowed to collide with a bridge abutment, which stops it in 0.56 s. What is the magnitude of the average force that acts on the car during the impact? Can you explain your answers?

Public Comments

1. Since the car goes from 15 m/s to 0 m/s in .56s, what is the average acceleration? Knowing that and that the vehicle is 2300kg, what is the force involved?
2. You know from Newton's Laws that F = ma. Now i'll make a substitution: F = m(Δv/Δt). This makes sense because acceleration is the change in velocity. Now, let's use this formula to do the problem: F = m(Δv/Δt) F = m(vf - vo) / Δt F = 2300(15) / 0.56 F = 61,607 N