"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

I wrote the above before seeing the MB episode.
I have now watched it and am impressed with their experiment with actual
vehicles.

However, they have committed another glaring physics error. Anybody
else catch it too? Hint: it has to do with the clay & pendulum experiment.
Art