A person’s head is subjected to an impulse of 116.93 Ns in a car collision. If a force of 1,990.51 N fractures the cheekbone,

Question

A person’s head is subjected to an impulse of 116.93 Ns in a car collision. If a force of 1,990.51 N fractures the cheekbone, what is the minimum time the cheekbone can be in contact with the steering wheel in order to NOT fracture?

Answer 1

The head get an impulse of 116.93 Ns and the impulse transform into the momentum of the head with the same value 116.93 kg*m/s. When the head hit the steering wheel, it will get another impulse from the steering wheel and lost all the momentum. The impulse from the steering wheel if F*t = 116.93 Ns. And if there is not fracture in the cheekbone, the maximum force from the steering wheel F should not exceed 1990.51 N (F<1990.51), so the contacting time of the steering wheel and the head t >= 116.93/1990.51 = 0.0587s. Therefore the answer is that the minimum time is 0.0587 second.