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I How do I state 2nd law of thermodynamics for an open system

  1. Jan 11, 2017 #1
    Ecosystems are open systems, they receive solar energy and other materials from outside the ecosystem and migration of animals is also witnessed.

    I read Physics uptil class XII and have done a bit of research on google books and have come across these three books:

    1.Towards a Thermodynamic Theory for Ecological Systems, pg-41

    2.Thermodynamics of Non-Equilibrium Processes for Chemists, pg-9

    3.Ecosystem Ecology, pg-35

    P.S. I couldn't come up with anything statement.
    I'm not sure if I posted on the right sub-forum. Let me know if this is suitable to other sub-forums and tell me why do you think so.
     
  2. jcsd
  3. Jan 11, 2017 #2

    Demystifier

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    There is neither 2nd law nor 1st law for an open system.
     
  4. Jan 11, 2017 #3

    DrDu

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    You can set up bilance equations for energy entropy etc. The one for entropy contains both transport terms (e.g. when an animal enters or leaves your system) which can be positive and negative and entropy production terms which can only be positive, due to the second law.
     
  5. Jan 11, 2017 #4
    This is not correct.
     
  6. Jan 11, 2017 #5

    Andy Resnick

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    Of course there is- usually written as balance equations.
     
  7. Jan 11, 2017 #6

    Andy Resnick

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    As DrDu mentioned, there are balance equations that can be written down, a crude version for entropy is here:

    http://www.learnthermo.com/T1-tutorial/ch08/lesson-B/pg04.php
     
  8. Jan 12, 2017 #7

    Demystifier

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    Thanks for the correction! :woot:
     
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