Question(Physics 20) about Power(watts)

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AI Thread Summary
To calculate the power output of an electric motor pulling an 8.5x10^2 kg elevator at a constant velocity of 1.00 m/s, the key is recognizing that acceleration is zero, meaning the force required is equal to the weight of the elevator. The power can be determined using the formula P = F * v, where F is the gravitational force (weight) and v is the velocity. Since the weight can be calculated as mass times gravity, this simplifies the process. The discussion highlights the importance of understanding the relationship between power, force, and velocity in this context. Ultimately, the focus is on finding the correct formula to compute power without needing time or work directly.
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Homework Statement



An 8.5x102 elevator (including occupants) is pulled up at a constant velocity of 1.00 m/s by an electric motor. Calculate the power output of the electric motor.


Homework Equations



P=W/t

F=ma

v=d/t

a=v/t

The Attempt at a Solution




Having trouble figuring out what the acceleration and time are in order to find force times distance(Work)

Thank you for your help!
 
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Hi Jyote25! :smile:
Jyote25 said:
An 8.5x102 elevator (including occupants) is pulled up at a constant velocity …
…
Having trouble figuring out what the acceleration and time are in order to find force times distance(Work)

acceleration is zero

time of what? :confused:
 
Is time really needed to solve this equation? I guess not since we've already figured out that Acceleration is zero. But in order to find work we still need distance...ideas?
 
Jyote25 said:
Is time really needed to solve this equation? I guess not since we've already figured out that Acceleration is zero. But in order to find work we still need distance...ideas?

very true :smile: …

but who asked you for the work? :confused:​
 
Well, in order to find Power we need work to find Joules/second, which equates to a Watt, which is going to be the 'power output' of the motor. P=W/t
 
yeeees … well, since you don't know the work and you don't know the time, that's a teeny bit unhelpful! :biggrin:

hint: do you know any formula for power that involves force instead of work? :wink:
 
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