Recent content by shakeybear

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    Working out signs of work and heat for entropy change question

    Thanks, but to be clear the problem is not really how to solve this, as far as I'm aware I've already solved it, unless someone corrects me. The problem I have now is explaining why it works. Andrew provided some insight into this but I'm still not convinced as to why the value of work is...
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    Working out signs of work and heat for entropy change question

    Thanks for your reply. Which part looks shakey exactly? is your formulation -95/275 + Qroom/295 = 0 Not equivalent to mine with Qh = Qroom? -95/275 = -0.345 101.9/295 = 0.345
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    Working out signs of work and heat for entropy change question

    Andrew: Interesting. I can't use that formulation of COP though as I only know Qc. Do you think my conclusions, that for this ideal case the entropy changes should cancel is reasonable? If so then there's nothing very dramatic I can change in the working. If I understand you correctly what I...
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    Working out signs of work and heat for entropy change question

    N.B. My set question is actually almost identical to another posted here https://www.physicsforums.com/showthread.php?t=368672 but my question is not answered there. Homework Statement The temperature inside a refrigerator is 275K. The room containing it has a temperature of 295K. In...
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