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Homework Help: Thermal energy question?

  1. Mar 8, 2009 #1
    Thermal energy question??

    1. The problem statement, all variables and given/known data
    a 500g iron rod has a temp. of 25 degrees C. how much thermal energy must be added to the rod to double the average kinetic energy of the iron atoms?


    2. Relevant equations
    EH = mc[tex]\Delta[/tex]T


    3. The attempt at a solution
    EH = (0.005 kg)(452 J/kg x [tex]\circ[/tex]C)
    = 56.5 J
    but the answer should be 6.73 x 104
    help?
     
  2. jcsd
  3. Mar 8, 2009 #2

    Andrew Mason

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    Science Advisor
    Homework Helper

    Re: Thermal energy question??

    You have to show your work completely. '

    First of all, how many kg does 500 grams represent?

    What temperature does the iron have to reach in order to double its kinetic energy?

    AM
     
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