Calculating Constant speed of an Elevator Rising

AI Thread Summary
To calculate the constant speed of an elevator with a motor power of 14 kW and a mass of 1100 kg, the relevant equations include gravitational potential energy (mgh) and kinetic energy (1/2 mv^2). The power produced by the motor can be equated to the work done per second, which is 14 kJ. To find the speed, one must determine how much height can be gained per second using the power output. The discussion highlights a need for algebraic manipulation to connect power, mass, and speed effectively. The key takeaway is that sufficient information is available, but proper application of physics principles is necessary for the solution.
Millacol88
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Homework Statement


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


Homework Equations


I'm not really sure. Probably Gravitational potential = mgh. Kinetic energy = 1/2mv^2 because its looking for speed.


The Attempt at a Solution


I'm really not sure. It doesn't seem like enough information is given to solve for anything. There's probably some algebraic manipulation I'm missing.
 
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Consider work done per second (14 kJ) - what increase in height does that correspond to (14kJ = mgh)?

-S

Millacol88 said:

Homework Statement


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


Homework Equations


I'm not really sure. Probably Gravitational potential = mgh. Kinetic energy = 1/2mv^2 because its looking for speed.


The Attempt at a Solution


I'm really not sure. It doesn't seem like enough information is given to solve for anything. There's probably some algebraic manipulation I'm missing.
 

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