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Work can create heat but heat can't create work

  1. Sep 8, 2014 #1
    Suppose we refine some of terms in thermodynamics based on the follow statements:
    1. All energy has two components: work energy and heat energy.
    2. Work is the change in work energy which is equal to the energy available to do work.
    3. Heat is the change in heat energy which is equal to the energy unavailable to do work.
    4. Work can create heat but heat can not create work.

    How would these changes effect the transfer energy between a hot(h) and cold(c) containers of water?

    The hot container is a higher energy state therefore it holds more work energy than the cold container.
    Therefore the energy transfer is:

    First law:
    Energy (hot)(-) + Energy (cold)(+) = 0
    (Energy release from hot container is equal to energy absorbed by the hot container)

    Second law:
    The change in work energy (hot) is greater than the change in work energy (cold)
    Or work done by the (hot) is greater than the work absorbed by the (cold)
    Work (hot)(-) + Work (cold) (+) = Total system work change(-)

    The change in heat energy (hot) is less than the change in heat energy (cold)
    Or heat (hot) is less than the change in heat energy (cold)
    Heat (hot)(-) + Heat (cold) (+) = Total system heat change (+)

    Summary:
    To maintain the first law the total change in Energy must be zero, therefore
    Total system work change (-) + Total system heat change (+) must be equal to zero

    Another example of this is the constant enthalpy process. (throttling)
    During this process the energy change is zero but
    the energy available to do work (Work) is converted to energy unavailable to do work (Heat).

    With this approach the entropy and the total system heat change both increase during the transfer of energy between two medium.
    Also this would apply to all energy (potential, kinetic and etc.)

    What are the problems with approach?
     
  2. jcsd
  3. Sep 8, 2014 #2

    rcgldr

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    Homework Helper

  4. Sep 8, 2014 #3

    Dale

    Staff: Mentor

    Heat can do work, that is the basis of all heat engines.

    We do not do personal speculation. If you have questions about mainstream thermodynamics then you are free to ask them here, but not speculate on possible changes to thermodynamics.
     
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