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I think he's talking about 65mph delta-V, referring to the change in velocity at the (nearly instantaneous) time of collision. Two cars rubbing like that won't produce a 65mph delta-V in the way that a brick wall will. It might be 5-10 mph, which will be enough to shock people but not fatal. He's right that 65 mph delta-V is almost uniformly fatal.

Likewise, if you jump out of a moving vehicle at 65mph, you'll get banged up badly but might not die, because you don't lose 65mph of speed the first time you hit the ground, since you're hitting it obliquely. On the other hand, if you jump from enough height to reach 65mph and hit the ground directly, you're almost certainly dead.




Right, and most crashes on the highway aren't fatal, and aren't in to immovable objects. So, I kind of don't the point of the comment.

Surely sometimes they are in to immovable objects, of course, and those ones are pretty bad.

Even worse are side impacts on trees, electrical poles and light posts.




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