Car Collisions

1. The problem statement, all variables and given/known data

Hi, could someone help me with some physics homework for a head on collision between a truck and a car. Truck and car are going the same speed (50mph) but truck weighs 5 times more than car.

Q.1. What is the force on each car?
Q.2. What is the impulse?
Q.3. Explain in detail using work-energy theorem why it is worse to be in the car
Q.4. If the vehicles collide at 50mph how would the impact compare for both vehicles to that of a collision with a solid wall?

2. Relevant equations

I = Ft = change in momentum
F = ma

3. The attempt at a solution

Think I know Q’s 1 and 2. The force of collision is equal and opposite and so is the time of the collision therefore I think both impulse and force will be the same. Using F =ma the acceleration will be much greater on the smaller car.

My questions:

How does this bigger acceleration cause a greater kinetic energy of the car as I thought KE is proportional to momentum and the momentum change is the same for both vehicles? I’m a bit unsure how you relate forces and accelerations to kinetic energy.
For the last part I’m not sure – I think the truck will experience an impact which is not as bad as colliding with a wall. Does the car experience an impact worse than colliding with a wall? not quite sure why though in terms of KE, impulse etc.

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