# physics

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A 7.40 lb rock sits on top of a 76.0 foot cliff. it is pushed off. What is the energy in Joules of the rock just before it hits the ground?

• physics -

If you want it in Joules, use SI units for mass, g and height H.

E= M g H is the kinetic energy just before it hits the ground

M = 3.36 kg
g = 9.8 m/s^2
H = 23.17 meters

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