How does changing the duration of a collision affect impulse

[AjPat]

Homework Statement

Car bumpers are able to reduce the force of an impact by allowing the force to the spread over a greater duration of time. I am wondering how this affects the impulse between collisions because while increasing the time it is decreasing the force, both of which are proportional to impulse. So will the amount of impulse stay the same between collisions with different bumpers?

Homework Equations

p=mv

The Attempt at a Solution

I believe regardless of the bumper material or how effective it is, the collision will maintain its impulse. This is because to the extent to which the force is reduced the time is greatened leading to no net change in the impulse experienced.[/B]

 

[PhanthomJay]

Yes, correct, but a more precise answer can be arrived at by noting the definition of impulse in terms of momentum