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Question
A box of mass 300 kg has gravitational potential energy stored in it equal to 29400 J. Find the height of the box above the ground. (Take g = 9·8 N kg-1).
Solution
m = 300 kg,
P.E. = 29400 J,
g = 9.8 N kg-1,
h = ?
P.E = mgh
29400 = 300 × 9.8 × h
h = `29400/(300 xx 9.8)`
h = `29400/2940`
h = 10 m
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