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Homework Help: Energy, Efficiency Question

  1. Aug 7, 2012 #1
    1. The problem statement, all variables and given/known data
    The energy lost operating a low-speed chairlift is the same as the energy lost operating a high-speed lift of equal path length. What happens to the efficiency when you change from a low speed to a high speed chairlift?

    2. Relevant equations
    We know that high speed chairlifts use more power so that they can go faster.

    3. The attempt at a solution
    My initial thought was that it would be less efficient because more power is used... but if they stay the same, less of the power will be wasted... making it more efficient??

    Please help!!

    Thank you
  2. jcsd
  3. Aug 7, 2012 #2


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    Staff Emeritus
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    Gold Member

    What is the definition of efficiency that you are using?
  4. Aug 7, 2012 #3
    The ratio of the output (useful work) to the input (total energy used)

    I read that regardless of speed, both the slow and fast chairlifts have identical efficiency, but I don't understand this.
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