161
Physics, Astronomy & Cosmology / Re: Why does double the velocity double the momentum and quadruple the KE?
« on: 28/09/2021 04:29:33 »Now do it to the parked car situation. One car parked (no KE). One going 100, so KE is 5000. After the hit, both cars are moving at 50, so KE is 2500 total. Total energy dissipated is 2500, shared between the cars so 1250 each. Same change in KE dissipated equally by both cars, so same damage as the slower speed head-on.Your analysis assumes that the parked car doesn't have brakes.
On the other extreme, we can assume that the car is perfectly braked, or bolted to the ground. In this case, the whole KE is dissipated by the moving car.
In real life cases, they're mostly between those two extremes. So the OP's intuition is justifiable.
The following users thanked this post: Curious Cat