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Question
To what height should a box of mass 150 kg be lifted, so that its potential energy may become 7350 joules? (g = 9.8 m/s2)
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Solution
Mass of the box, (m) = 150 kg
Acceleration due to gravity, (g) = 9.8 m/s2
Potential energy, (P.E) = 7352 J
Let the height above the ground be (h)
We can calculate potential energy as,
(P.E) = (m)(g)(h)
So, height can be calculated as,
`h = (P.E)/((m)(g)`
So ,
`h = 7350/((150)(9.8)` m
= `7350/1470` = 5 m
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