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To: Duke C.
my physics is rusty

That would be entropy.

Why do you want to square v?

9 posted on 05/16/2015 3:58:49 PM PDT by 9thLife ("Life is a military endeavor..." -- Francis)
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To: 9thLife

“Why do you want to square v?”

kinetic energy

E = (mv**2)/2

70 mph is just over 102 ft/sec, not 88 ft/sec

bowling ball mass of 15 pounds equates to 0.466 slugs (pounds are a unit of force, not mass)

gives us about 2425 foot-pounds of energy. So the analogy of a BB hitting an auto is not too far off.

Much about a collision result depends on the materials of the colliding objects, their angle of impact, their shape, etc. Momentum is a factor: the scalar product of mass and velocity.

To carry on with the analogy, a human struck by that 15-pound bowling ball traveling 70 mph (102 ft/sec) will sustain injuries quite different from a human struck by - say - a 30 cal bullet traveling 2700 ft/sec (common impact velocity fired from many hunting rifles), though the kinetic energy of the projectiles are nearly identical.


25 posted on 05/16/2015 4:19:47 PM PDT by schurmann
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To: 9thLife
Why do you want to square v?

Because that's the formula for kinetic energy. Mass time 1/2 the square of velocity.

76 posted on 05/16/2015 7:34:09 PM PDT by IronJack
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