Question

The use of air bags in cars reduces the force of impact by a factor of 110.(The resulting force is only as great.) What can be said about how the airbag changed the duration of the collision?

Answer 1

the answer is C. it increases by a factor of 110, i got 100 on the test

Answer 2

The variation of momentum (= the impulse) of the car during the impact is

`\Delta p = F \Delta t`

`\Delta p` does not change whether the car has an airbag or not, because

`\Delta p = m\Delta v`
and 1) the mass of the car is always the same 2) the change in velocity of the car is always the same,

so if
`\Delta p` is constant and F is reduced by a factor 110, then
`\Delta t` (the duration of the collision) must be increased by a factor 110 with the airbag.