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A comment on The Francis Scott Key Bridge in Baltimore, Maryland Has Collapsed. Parent comment

Re:The Francis Scott Key Bridge in Baltimore, Maryland Has C... by sho on Wednesday March 27, 2024 @12:39AM (#39835753)
Hm. I'm no physicist but I think your math is off. Remember it's velocity squared. Your car going that fast is has more than a kiloton of TNT or approaching 5 terajoules of energy... that can't be right.

For a 2 tonne car, my very rough math puts it at more like 2100 mph.

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Re:The Francis Scott Key Bridge in Baltimore, Maryland Has C... by snarkconjecture on Wednesday March 27, 2024 @01:51AM (#39836043)
Momentum is just mv, not mv².
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Re:The Francis Scott Key Bridge in Baltimore, Maryland Has C... by sho on Wednesday March 27, 2024 @02:55AM (#39836305)
I can't edit my post now, but to be clear I was talking about kinetic energy. I would have thought momentum is not a very useful thing to talk about in a case like this where there was some pretty obvious transformation of energy into damage, etc.

As I said though, I'm far from a physicist so happy to be schooled if I'm way off...

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