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Homework Help: Heat Capacity and Energy supplied

  1. Jan 21, 2007 #1
    I'm stuck on some basic physics...

    I'm using the formula E=mc (delta T/delta t) where E is energy, m is mass, c is specific heat, T is temperature and t is time, to calculate the energy used in heating a volume of air to a certain temperature.

    Assuming that pressure is of that at sea level, I come up with a rate of heating of 12.56J per second, for a 16K rise in temperature over 10 hours, for a volume of air of 24m3.

    This seems a little high, what did I do wrong?
  2. jcsd
  3. Jan 21, 2007 #2

    we have just been told that E=mc*deltaT, in both physics and chemsitry...?

    where did you get the (deltaT/deltat) ?

    EDIT: ah ha! i see where the discrepancy lies... you are working out energy per second. sorry.
  4. Jan 21, 2007 #3


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    Staff Emeritus
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    That's about the same number I get...but next time:

    1. Please post such questions in the Homework & Coursework subforums, and
    2. Use the template provided (and write down the original question EXACTLY as it was given to you).
  5. Jan 22, 2007 #4
    Thanks, but it's not homework! I'm trying to work it out for myself for another project, needed to check the answer before I went forward with the work!

    That IS the original question, shows why I shoudnt be a teacher!
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