The second floor of a house is 6m above street level. How much work is reguired to lift a 300 kg refrigerator to the second story?

Answer: 17.658kJ

Explanation:

The work done in lifting the refridgerator is given my

W = F. d

Where W = Work done, F = Force and d = distance/height to be covered by that force = 6m

But F = mg (this work is done against gravity)

Where m = mass of fridge and g = acceleration due to gravity.

F = 300kg * 9.81m/s^2

= 2943N

W = Fh (where h is the height to be scaled by the force)

W = 2943 * 6

W = 17658J

17.658kJ of work is needed to lift the refridgerator to a height of 6m