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A military helicopter lifts a 75 kg floo...

A military helicopter lifts a 75 kg flood survivor 16 m vertically from the river by a rope. If the acceleration of the survivor is g/10, how much work is done on the survivor by (a) the force from the helicopter and (b) the gravitational force on her ? Just before she reaches the helicopter, what are her (c) kinetic energy and (d) speed ?

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The correct Answer is:
`(a) 1.3xx10^(4)J; (b) -1.2xx10^(4)J; (c) 1.2xx10^(3)J; (d) 5.6 m//s`
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