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How high most a body be lifted to gain a...

How high most a body be lifted to gain an amount of P.E. equal to K.E. is when moving at speed 20ms^(-1). (The value of acceleration des to grity at a place is `(9.83ms^(-2))`

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The correct Answer is:
`mgh=1/2mv^(2)`
so h=20.2m
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