91Ó°ÊÓ

The impulse on an object is equal to the change in the momentum of that object.

Let\(\Delta {P_1}\)be thechange in momentum of the system of two cars when they collide and stick together.

Let \(\Delta {P_2}\) be the change in momentum of the system of two cars when they collide and rebound backward.

Now, when the cars rebound backward, the change in momentum is more than when they stick together. This is because when they stick together, their final states will either have a common speed or they will be at rest. However, if they rebound, they will have different speeds.

Therefore,

\(\Delta {P_2} > \Delta {P_1}\)

The change in momentum is more when the cars rebound. The cars feel more impulse for the rebound situation because the change in momentum is directly proportional to impulse.

In the case of the rebound situation, the time of contact for collision is very less and it imparts a large amount of force on the passengers or occupants inside the cars. So, the rebound situation will cause more damage than when they remain together.