The work done in lifting a box onto a platform does not depend upon how fast it is lifted up. Explain your answer giving proper reasoning.

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(N/A) The work done $(W)$ in lifting a box of mass $(m)$ through a vertical height $(h)$ against the gravitational force $(F = mg)$ is given by the formula $W = F \times h = mgh$.
In this expression,the work done depends only on the mass of the object $(m)$,the acceleration due to gravity $(g)$,and the vertical displacement $(h)$.
Since the time taken or the speed at which the box is lifted does not appear in this formula,the work done is independent of the rate at which the box is lifted.

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