Head-on Collision on the Road

Well, you can't go wrong with that bet anon

Wrong, it's the equivalent of hitting a wall at 20km/h. Mythbusters did it, look it up on YouTube :D

Actually that's incorrect. the cars will experience the same amount of force as if they hit a wall at 20km/h. This has been shown in test. The best understanding for this i can think of is Newtons third law which is put simple every action has an equal and opposite reaction.

For this assume the cars are equal in mass and speed to simplify.

Lets say car 1 receives a force of 500 newtons it will therefore apply 500 newtons to the object it's impacting (in this case the other car 2). Car 2 will experience 500 newtons of force and apply 500 newtons of force to car 1. The reaction forces are being transferred between the two cars forming one system (remember the impact forces are in independent systems). The reaction forces are therefore equal and opposite and therefore cancel each other out.

Now if one vehicle has higher kinetic energy then the other (is faster and or heavier) the vehicles with lower kinetic energy will experience a force greater then it would if it impacted a wall while the higher kinetic energy vehicle would experience less. This is because the vehicle with less energy will be pushed pack experiencing an acceleration greater then it's absolute velocity resulting in a larger force. The heavy vehicle will not completely stop and therefore will experience a lesser force then hitting a wall. The reaction forces just like the equal car example will still cancel out.

I bring physics to the house!

but this would be untrue if there was weight differences, right?

just read my reply to the anon.

Based off logic. They have it going from smallest to largest, Day, Month, Year.

We have it going second largest, smallest, biggest. Completely illogical.