The force that a moving object exerts on another object upon colliding with it is rather the change in momentum divided by the amount of time elapsed during the collision.
F = Δp/Δt
F = force, Δp = change in momentum, Δt = elapsed time
Usually we say momentum is proportional to mass instead of saying momentum is proportional to weight. But sure, for two objects on the same planet, greater weight implies greater mass. Momentum is the product of mass and velocity:
p = mv
p = momentum, m = mass, v = velocity
So we have two identical cars on the same planet with one car traveling 30mph faster than the other. Let's say they both collide with a tree, both coming to a rest, and the collisions take the same amount of time to happen. The faster car loses a greater amount of momentum over the same amount of time, therefore delivering a greater force.
Choice B
