Question

the work done in lifting a box on to a platform does not depend upon how fast it lifted up. explain your answer giving proper reason?

Answer 1

Work done does not depend on the velocity of the body.

W = FS

Where W is the work done in lifting a box

S is the distance  

F is the gravitational force

So the work done in lifting a box on to a platform does not depend upon how fast it is lifted up.

Answer 2

No, it certainly not depends upon how fast the box is lifted onto a platform.
Explanation:
Work done in lifting the box onto a platform = W = m g h
Where 'm' is the mass of the box, 'g' is the acceleration due to gravity at that place and 'h' is the height through which the box has been lifted. Hence, 'how fast it is lifted' does not have any effect.
Hopefully my answer helps.
Thanks.