# physics

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A boulder with a mass of 2,500 kg on a ledge 200 m above the ground falls. If the boulder's mechanical energy is conserved, what is the speed of the boulder just before it hits the ground?

• physics -

1/2 m vf^2=m*g*height
solve for vf

notice mass divides out.

vf=sqrt(2gh)

• physics -

How do you figure miles per hour?

• physics -

• physics -

I meant meters per second

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