"Artemus" wrote in message
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"Existential Angst" wrote in message
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Awl --

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.

In terms of physics each car has energy = 1/2mv^2, where m = mass
and v= velocity. For 1 car going 50mph: 1/2m(50)^2 = 1250m units
The total energy for both cars is 2500m units.
For 1 car going 100mph its energy is 1/2m(100)^2 = 5000m units.
Clearly not the same thing.
Art

Right on Art. This (two cars doing 50 same as one car hitting wall at 100)
is a myth that has to be dispelled.
I have given up trying to set this right when it comes up in social
settings. Isn't worth the effort. Of course, in technical or engineering
settings the subject doesn't even come up because they all know the right
answer.
It's the media that feeds this falsehood.

Ivan Vegvary