1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Engine efficiency

  1. Feb 14, 2007 #1
    An engine releases 0.490 kJ of heat for every 0.120 kJ of work it does. What is the efficiency of the engine?

    I am having trouble with this problem.
    I tried

    Wnet/ heat input = efficiency
    0.120/0.450 = 0.27
    but it says it is the wrong answer. (correct answer is 0.21)
     
  2. jcsd
  3. Feb 14, 2007 #2

    berkeman

    User Avatar

    Staff: Mentor

    The efficiency is the useful work divided by the total energy. What is the total energy in terms of the useful work and the waste heat generated?
     
  4. Feb 14, 2007 #3
    thanks!

    0.120/(0.450+0.120) = 0.211
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Engine efficiency
  1. Engine efficiency (Replies: 0)

  2. Efficiency of engine (Replies: 8)

  3. Efficiency of a engine (Replies: 2)

Loading...