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Question 1190583: An elevator has a mass of 1500 kg and is carrying 10 passengers through a height of
15 m from the ground. The time taken to lift the elevator to that height is 0.75 minutes.
Calculate the power required by the motor to lift the elevator if the mass per passenger
is 50 kg.
Answer by math_tutor2020(3817)   (Show Source):
You can put this solution on YOUR website!
0.75 minutes = 60*0.75 = 45 seconds
1 passenger = 50 kg
10*1 passenger = 10*50 kg
10 passengers = 500 kg
Add on the mass of the elevator itself
500+1500 = 2000 kg
The force of gravity is pulling down on the 2000 kg combined mass at an acceleration of roughly 9.81 m/s^2
Force = Mass*acceleration
F = ma
F = 2000*9.81
F = 19,620 newtons
This is approximate the upward force needed to counterbalance the force of gravity, so that the system moves upward.
Work = Force*Displacement
Work = (19,620 newtons)*(15 meters)
Work = 294,300 newton meters
Work = 294,300 joules
power = (amount of work done)/(change in time)
power = (294,300 joules)/(45 seconds)
power = 6540 joules per second
power = 6540 watts
Answer: 6540 watts (approximate)
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