Power Problem regarding elavator

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To calculate the power required for a 255kg elevator that is 62.5% efficient and climbs 52.5 meters in 25 seconds, the formula P = change in energy over change in time is used. The gravitational potential energy (GPE) is calculated as GPE = mgh, where m is mass, g is acceleration due to gravity, and h is height. Efficiency must be considered, as a non-ideal process requires more energy than an ideal one; thus, the power output must be adjusted by the efficiency factor. The correct approach involves multiplying the calculated energy by the efficiency to find the actual power required. Understanding efficiency is crucial, as it directly impacts the energy calculations for non-ideal processes.
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Homework Statement


An 255kg elevator which is 62.5% efficient climbs 52.5 meters in 25 seconds. What is the power required to do this.

I'm just not sure how to incorporate efficiency in this.

Homework Equations


P= change in energy over change in time
GPE=mgh

The Attempt at a Solution



P= 255*9.81*52.5/25 Do I need to multiplay the numerator by 0.625? Could you please explain why or why not? Thanks in advance :)
 
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Will a non ideal process (<100%) require more or less energy than an ideal process?
 
billy_joule said:
Will a non ideal process (<100%) require more or less energy than an ideal process?
More. would I have to multiplay it by 1.625 then?
 
No. 1/1.625 = 0.615 ≠ 0.625
 

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