How Is Elevator Motor Efficiency Calculated?

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To calculate the efficiency of an elevator motor, first determine the work output and input using the formula Efficiency = (work out/work in) * 100. The work output can be calculated by finding the force exerted by the elevator and the distance it moves, while the work input is derived from the motor's power rating. It's crucial to convert the motor's power from kilowatts to watts for consistent units. The discussion emphasizes the importance of unit conversion and proper calculations to find the efficiency. Understanding these calculations is essential for evaluating motor performance.
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An 8.5x10^2kg elevator is pulled up at a constant velocity of 1.00m/s by a 10.0kW electric motor. Calculate the efficiency of the motor.

Efficiency = work out/work in * 100

How do I calculate "work out/work in" using the information given?
 
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hi larry21! :smile:

(try using the X2 icon just above the Reply box :wink:)

find the force, then find the power, then divide by 10.0 …

what do you get? :smile:​
 
thanks, that was a great help. However, do I need to convert the "kW" to "W"
 
oh yes … you'll need both to be in the same units :smile:
 

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