# physics

A boy jumps from a wall 3m high. What is an estimate of the change in momentum of the boy when he lands without rebounding?
the answer is 5x10^2kg/ms, but how?

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1. what's his mass?

momentum is ... m * v

his velocity is ... √(2gh) = √(2 * 9.8 * 3)

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2. it didn't say:(

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3. so the question is "estimating" his mass to be about 65 kg (143 lbs)
... a reasonable number

but a very poor question

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