The Wall

QUESTION:

Which would be more damaging?

driving into a massive concrete wall
driving at the same speed into a head-on collision with an identical car traveling toward you at the same speed
There would be no difference in damage.

drawing of answers a and b

ANSWER: C

Both situations are equivalent because either way, your car rapidly decelerates to a dead stop. The dead stop is easy to see when hitting the wall, and a little thought will show that the same is true when the cars hit each other. If the oncoming car were traveling slower, with less momentum, you'd keep going after the collision with more "give," and less damage…to You! But if the oncoming car had more momentum that you, it would keep going. You'd snap into a sudden reverse with greater damage. Identical cars at equal speeds means equal momenta—zero before, zero after the collision.

drawing of the crash results

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