A large store escalator that is designed to transfer customers to one floor to another, a vertical distance of 8.0m. It takes each person 20 seconds to ride from bottom to top of the escalator. Explain how you would determine the power of the escalator motor.

1 answer

Guess mass of person, say 80 kg
guess how many on elevator, say 50 (guess high, we want a strong enough motor)
so total mass of people on elevator at one time = 80*50 = 4,000 kg
energy change = m g h
= 4,000 * 9.8 * 8 = 316,600 Joules
divide by 20 seconds
----> 15,688 Watts
If the efficiency is 40% then you need about a 40 kw motor