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Homework Help: Heat from Entropy & Temp

  1. Nov 5, 2005 #1
    I am given the number of moles of an ideal monotomic gas. I am also given a chart with a graph of temperature plotted as a function of entropy.

    One of the questions is: find the heat that was transferred to the gas.

    How do I find that? I thought about saying:

    dS = dQ/T <=> dQ = T dS

    then I found the slope of the graph with respect to S and found the y-intercept. So now I had T in terms of S and I said:

    dQ = (mS + b) dS

    taking the integral of both sides I found Q and was able to easily integrate from initial entropy to final entropy. But I got the answer wrong. I don't want to do it all over again, unless I am sure this is the right approach. Is there an easier way?

    This is problem #8 in Chapter 21 of Halliday/resnick/walker 6th edition.
     
  2. jcsd
  3. Nov 5, 2005 #2
    O.k. I overcame my sloth and did it again. I got the right answer!

    But it seems overly involved. Is there an easier way?
     
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