Suppose that the car is stopped from 60mph within right after the collision and the driver (75kg) didn’t push the brake.
Seatbelt is non-stretchable and produces a constant force to stop the driver in 10cm. Calculate the acceleration of the driver and the force that the seatbelt acts on the driver for above two conditions.
Time for the driver to hit the seatbelt: t=d/v
Force that the seatbelt exerts on the driver: F=m(vo-vt)/t
Acceleration of the driver: a=F/m
The Attempt at a Solution
Time for the driver to hit the seatbelt:
t=d/v = 0.1m/(27m/s) = 3.7ms
Force that the seatbelt exerts on the driver:
F=m(vo-vt)/t = 75kg(27m/s - 0m/s)/3.7ms = 547,297N
Acceleration of the driver:
a=F/m = 547,297N/75kg = 7,297.3 m/s^2
Is this right, the force seems so high?