elevator lifts-work

Question

An elevator lifts 6 occupants up 21 floors (76 meters) at a constant speed. The average mass of the occupants is 77 kg. How much work is done by the elevator.

Answer 1

Number of occupants of lift = 6

The average mass of the occupants = 77 kg

Total mass of occupants traveled is m = 6*77 = 462 kg

Distance traveled up h = 76 m

Acceleration due to gravity = 9.81 m/s²

Total Force F = ma = mg = 462*9.81 = 4532.22

Total Work done = Total Force × Distance = F×h

= 4532.22×76 = 344448.72 N-m

Total work done by the elevator is 344448.72 N-m