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Idea 2 for how to break the second law of thermodynamics

  1. Jun 27, 2013 #1

    I have another idea for how to break the second law of thermodynamics, and I don't see where this one cracks either. I would be glad if someone could explain this to me.

    Kelvin-Planck statement of the second law:

    "No process is possible whose sole result is the absorption of heat from a reservoir and the conversion of this heat into work."

    Clausius statement of the second law:

    "No process is possible whose sole result is the transfer of heat from a cooler to a hotter body."

    Here it goes:

    First see the drawing below:


    As you can see on the drawing, the right body has a bigger opening for EM radiation to escape than the left body does. The two bodies start of at the same temperature. But if more EM radiation goes from the right body to the left body, than vice versa, with time, the left body will heat up, and the right body will cool down. This clearly violates the second law, see Clausius statement above.

    This is a hypothetical thought experiment. I realize the practical problems with perfect mirrors and lenses, but theoretically it should be possible?

    Grateful for help!
  2. jcsd
  3. Jun 27, 2013 #2
    Some clarification:
    If the bodies are the perfect mirrors, then they do not absorb any radiation, and cannot heat up.
  4. Jun 27, 2013 #3
    To clarify:

    The black dot in the middle is the body which emits radiation from being warm. The half circle, and the circle with a little opening, as indicated in the drawing, are the mirrors
  5. Jun 27, 2013 #4

    Vanadium 50

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    Perpetual motion machines are not an acceptable subject here - please reread the PF Rules. We let the first thread stand because we had hoped to educate you on why they were impossible, but we will not have a parade of PMMs here.
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