How does Newton's second law of motion apply to the design of car safety features?

I have a physics essay that asks how does newtons laws of motion apply to the design of car safety features, i've already done the first and third but i can't find one for the second law.How does Newton's second law of motion apply to the design of car safety features?The force experienced by a driver in a collision is given by

F = m(v - u)/t

i.e. the rate of change of momentum (Newton's second law)

So if you can increase the time it takes for the driver's head to come to rest (by fitting an airbag), the force will less.