Question

A 60.0-kg person is in an elevator with a mass of 2000 kg. The elevator moves vertically up through a distance of 24.0 m with a constant speed of 4.00 m/s. How much work is done on this elevator system? Use g=10.0m/s^2.

Answer 1

The mass of the (elevator + person) is (2,000 kg + 60 kg) = 2,060 kg .

The weight is (mass x gravity) = (2,060 x 10) = 20,600 newtons

Work = (force x distance) = (20,600 newtons x 24m) = 494,400 joules

The speed, acceleration, and how much time it takes don't make any
difference, unless you want the average power during the lift.

         Power = (work)/(time) =
           494,000 J / (24/4 m) =
           494,000 J / 6 sec = 82,400 watts      wow !