So in the past few weeks, I have witnessed a few car accidents throughout the Rochester area and I thought doing the physics of crashing a car would be quite the topic. When a car and a truck collide, there is a change in momentum. Momentum is equal to the mass multiplied by the velocity of the object. When the car with a smaller mass hits a truck with a higher mas but , there is a shift of momentum between the two objects. therefore an heavier object can cause a larger impact due to the greater mass.