Edward A. Falk wrote:
In article ,
Artemus wrote:
Are two cars hitting each other at 50 mph the same as 1 car hitting an
immovable wall at 100 mph?
Short answer = no.

Longer answer. If the 2 cars are the same mass(weight) they will both
come to a stop at the point of the collision. Now imagine a brick wall
at that point and each car slams into a side. Each car goes from 50mph
to zero in both cases.

Now only use 1 car and the brick wall. That car still goes from 50mph
to 0mph.

I never thought of it that way.

I'd guess that two cars hitting each other at 50 would be equivalent to
one car going 100 hitting another car that was sitting still in neutral
with no brakes.

The outcome also depends on how rigid the cars are, not only their
masses. Imagine both 50mph cars are billiard balls. They meet head-on
and accelerate not from 50 to 0, but from +50 to -50. About the same as
a "softer" car hitting a wall and going +100 to 0.