How Much Power Does the Elevator Cable Exert in kW?

Thread starter needhelp1234
Start date Dec 7, 2008
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Average Rate Work

AI Thread Summary

To determine the average power exerted by the elevator cable, the formula P = Fv is used, where P is power in kilowatts, F is the force, and v is the velocity. The mass of the elevator cab is 3,000 kg, and it moves 165 m in 23 seconds, resulting in a constant speed. The force from the cable must counteract the gravitational force acting on the cab, which is calculated as F = mg, where g is the acceleration due to gravity (approximately 9.81 m/s²). The average velocity is calculated as v = distance/time, which equals 165 m / 23 s. By substituting the values into the power formula, the average rate of work done by the cable can be determined in kilowatts.

Dec 7, 2008

needhelp1234

The loaded cab of an elevator has a mass of 3.0 103 kg and moves 165 m up the shaft in 23 s at constant speed. At what average rate does the force from the cable do work on the cab?

I don't even know where to begin. The answer is in kW

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Dec 7, 2008

Irid

Employ a formula to calculate power:

P = Fv

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