What is the Constant Speed of an Elevator with a 14kW Motor and 1100kg Mass?

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SUMMARY

The discussion centers on calculating the constant speed of an elevator powered by a 14kW motor with a mass of 1100kg. Using the formula P = Fv, the calculated speed is 1.29 m/s based on the power output and gravitational force. However, a discrepancy arises as the textbook states the speed should be 13 m/s, leading to speculation about a potential error in the textbook. The participants confirm the correctness of the derived formula and question the feasibility of the textbook's speed value.

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A.J.
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Homework Statement


The motor of an elevator can produce 14kW of power, its mass is 1100kg. At what constant speed will the elevator rise?

Homework Equations


F=ma
W= Fd
P= w/t
Vav= d/t

The Attempt at a Solution


P= w/t
P= Fd/t
P= F * Vav
V= P/mg = 14000W/(1100Kg*9.8m/s^2)=1.29m/s

The book states the answer is 13m/s. I have no idea how I'm suppose to get this answer, please help. Thanks in advance.
 
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Hmmm, seems like there is a factor of ten missing somewhere. Are you sure you are using all the right values? Perhaps the book is wrong.
 
As you've derived, the equation P = Fv is correct, so it looks like a mistake in the book. An elevator going 13 m/s seems a bit fast if floors are approx. 5 meters apart.
 
Ok thanks guys.
 

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