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Homework Help: Efficiency of an engine

  1. Dec 13, 2009 #1
    1. The problem statement, all variables and given/known data
    A heat engine operating between 78.5oC and 204oC achieves 20.6% of the maximum possible efficiency. What energy input will enable the engine to perform 10.2 kJ of work?

    The only help I need with this is exactly what equation(s) to use. I would think thermal efficiency would be one equation(e=W/Qh) but not sure what else to use.
  2. jcsd
  3. Dec 13, 2009 #2
    You need to take a look at the carnot efficiency of the heat engine, this will tell you the maximum possible work for a heat engine operating between two temperature resivors.
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