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Homework Help: Motor efficiency

  1. May 5, 2006 #1
    In an assigment I'm using the general formula P=F*v, where P is the effect of a motor. The motor drives something through a series of sprockets, who's efficiency is 85 %, and so it seems intuitive to me to multiply the resulting P with 0,85 to get true effect, but apparently the solution divides by 0,85 which results in a higher P than to begin with. I don't get the logic in this, so if someone can explain why this is correct I would like to hear it.
  2. jcsd
  3. May 7, 2006 #2


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    Homework Helper

    What's the question?
    Could it be that you're given the final output power (that is, after the sprockets), and asked the power of the motor?
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