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Homework Help: Physics help with efficiency

  1. Nov 21, 2011 #1
    1. The problem statement, all variables and given/known data
    I am using a 5 kilowatt motor to pump oil to a holding tank which is 20 m above the pump. If the motor is 65% efficient, how many liters of oil can i pump per minute if 1 liter of oil has a mass of 1.30 kg?

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Nov 21, 2011 #2


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    Homework Helper

    Well if the efficiency is 65% how much is the work output of the motor?
  4. Nov 21, 2011 #3


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    Staff Emeritus
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    How much energy does it take to lift 1 liter of oil 20 meters? After accounting for the efficiency of the motor, how much energy per minute is furnished to the pump?
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