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How is light produced

  1. Apr 23, 2010 #1
    I am not quiet sure where should i post this question, so forgive me if i asked this question at the wrong place. Now my Question is that how can an intensely thermochemical process like burning of a fuel produce, something like light which is a electromagnetic wave ?
     
  2. jcsd
  3. Apr 24, 2010 #2

    mathman

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    Science Advisor

    The energy is absorbed by the constituents of the gas around the fire. This energy leads to electrons going into higher energy states. The electrons then drop back into lower energy states emitting photons. These photons are the em waves.
     
  4. Apr 24, 2010 #3

    Dale

    Staff: Mentor

    The light from e.g. a candle is essentially the same as the light from an incandescent light bulb, both are simply due to black-body radiation from a very hot object.

    http://en.wikipedia.org/wiki/Thermal_radiation
     
  5. Apr 25, 2010 #4

    mathman

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    Candle and light bulb are different. Light bulb is essentially black body. On the other hand candle light contains discrete lines as a a result of the process described above.
     
  6. Apr 25, 2010 #5

    Dale

    Staff: Mentor

    There may be a little of that, but the light from a candle is mostly just hot soot particles which give off blackbody radiation. That is why fires that give good light leave soot (candles) and fires which burn clean don't produce much light (alcohol).
     
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