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Homework Help: Which, if any, is/are valid forms of the Second Law of Thermodynamics?

  1. Jul 7, 2011 #1
    What I answered is in brackets...what did I answer incorrectly?

    • It is impossible to construct a device that, operating in a cycle, will produce no effect other than the extraction of heat from a reservoir and the performance of an equivalent amount of work. [True]
    • For all naturally occurring processes, Sgen > 0. [True]
    • It is impossible to construct a device that, operating in a cycle, will produce no effect other than the transfer of heat from a lower-temperature reservoir to a higher-temperature reservoir. [True]
    • It is impossible to construct a device that, operating in a cycle, will produce no effect other than the transfer of heat from a higher-temperature reservoir to a lower-temperature reservoir. [True]
    • Ein - Ein = ∆Esystem [False]
    • For all naturally occurring processes, Sgen ≤ 0. [False]
    • All of the above statements are true. [False]
     
  2. jcsd
  3. Jul 7, 2011 #2

    SammyS

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    [*] It is impossible to construct a device that, operating in a cycle, will produce no effect other than the transfer of heat from a higher-temperature reservoir to a lower-temperature reservoir. [True]

    I think this one is the problem.
     
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