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Homework Help: Gr 11. Thermal Energy *help*

  1. Oct 8, 2004 #1
    Does anyone know why I end up with the wrong answer?
    I went delta q is equal to m c delta t, the derived the equation delta t is equal to delta q divded by mc. I therefore did the math as 232 kJ divided by (10 kg times 4.2 x 10 ^3 j/kg C) and got 9.7 x 10 ^4, when the answer was supposed to be 5.5. Does any one know what I did wrong??


    Thank you in advance
     
  2. jcsd
  3. Oct 8, 2004 #2

    Diane_

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    Homework Helper

    Well, I did it using your numbers and ended up with 5.5. I have two thoughts:

    1) Watch your units. You're dealing with kilojoules in the numerator and joules in the denominator.

    2) Watch your arithmetic: That's 232000 divided by 10 divided again by 4200.
     
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