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Homework Help: Otto cycle engine

  1. Sep 2, 2015 #1
    1. The problem statement, all variables and given/known data

    An Engine works within Otto cycle where the compression ratio is 6, and 350 kJ of heat was added to it. Determine the efficiency of the cycle and the work done if Cp/Cv is 1.45

    2. Relevant equations
    Efficiency Otto = (1- r1-k)
    Efficiency (eff.) =Work (W) /Heat Transferred (Q)

    3. The attempt at a solution

    Efficiency Otto = (1- r1-k) ( r is the compression ratio, k is Cp/Cv)

    = 1-61-1.45

    = 0.5534 = 55.34% --> The efficiency of the cycle

    W=eff. * Q = 0.5534 * 350

    W=193.72 kJ --> The work done
    Last edited by a moderator: Sep 2, 2015
  2. jcsd
  3. Sep 3, 2015 #2


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    Homework Helper

    Your result looks fine, but use the "x2" button for an exponent. The efficiency is 1-r(1-k) instead of 1-r1-k and 1-61-1.45 is not 55.34%.
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