A pulley system is used to lift a 2000 newton engine up a distance of 3 meters The operator must apply a force of 250 newtons to the chain of the pulley system to lift the motor To lift the engine fi?

We cannot violate the principle of conservation of energy in any situation. Hence the work to be done in lifting 2000 N through a distance 3 m will be 6000 joule.

That same amount of energy is to be supplied. If suppose there be any loss of energy by some means then energy more than 6000 joule has to be supplied.

So with a force of 250 N the displacement to be made has to be 6000/250 = 24 m.