1. The problem statement, all variables and given/known data A car is involved in a collision when it is travelling at 24m/s. The driver , of mass 85kg, is brought to rest by the seat belt in a time of 400 ms . Calculate the average force exerted on the driver by the seat belt . Compare this force with his weight , and hence calculate the 'g-force' to which he's subjected by the crash, and comment on the likelihood of his sustaining serious injury. 2. Relevant equations 3. The attempt at a solution Well, I' use F=m (v-u)/t to find the average force exerted on the driver, am I correct ? Second question , can I use formula of work done to calculate the 'g-force' ? Logically, is it impossible the 'g-force' means the potential energy stored in the car ? Guide me please .