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Origin of thermal radiation in humans.

  1. Jan 6, 2013 #1
    hi, i m new to this forum,this is my first post,i have recently started studying heat transfer. i m am little bit confused about the origin of thermal radiation in human beings.i mean radiations are emitted when an electron jump from a shell/orbit which is far from the nucleus to a shell which is nearer to nucleus. let say from M shell to K shell..so my question is that are these activities are taking place in our body on atomic level like in DNA or whatever?
    your guidance will be much appreciated..
  2. jcsd
  3. Jan 6, 2013 #2


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    Human beings, like other mammals, are warm blooded. The body's internal metabolism generates heat by the oxidation of food consumed by the organism. In order to be able to cool the body, the internal temperature of the body is higher than the surrounding environment. This thermal difference allows the body of the organism to regulate its internal temperature.
  4. Jan 6, 2013 #3


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    Chemical reactions in cells produce the energy. The chemical reactions would involve the outermost (valence) electrons in the constituent elements; C, N, O, H, which form numerous organic molecules. One should be able to find data on the energy of different atomic bonds in molecules.

    See this article on metabolism - http://en.wikipedia.org/wiki/Metabolism

    Of course, the internal body is relatively low temperature - ~98-100°F, while surface temperatures can be lower depending on the environment.
  5. Jan 7, 2013 #4


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    The first thing you learn about how EM radiation interacts with matter is the Hydrogen Atom. An electron is in a state of Energy near a proton - i.e. a system with just two charges. The energy gaps for the H atom correspond to visible light photon energies. There are many other combinations of charges such as all the other elements and the combinations of atoms (molecules) and even huge numbers of atoms in solids (metals and people). Any change of the arrangement of charges within these more complicated systems can involve the emission or absorption of photons. At any temperature, there will be vibrations of the atoms within an object as they change shape and position and also movements of electrons; these are Energy Transitions. For an object at body temperature, the majority of the transitions correspond to energies in the IR part of the spectrum. Chemical processes in the body are the source of the energy for these transitions. No chemical reactions (death) would mean that the temperature would drop to room temperature.
  6. Jan 9, 2013 #5
    whao..this reminds of thermal imaging of death..i saw it on NAT GEO..thank you very much sir
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