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Light bulb

  1. Oct 22, 2011 #1

    i was wondering why the spectrum of an ordinary light bulb is continuous. i know that "i think it's thermodynamics" says that some temperature creates a specific continuous radiation, but how is this reconcilable with quantum mechanics and e.g. a sodium gas, that emits only a tiny yellow spectrum? and to which energy transitions does thermodynamics here refer to? where does this energy come from? i mean, if it is the crash of atoms that have such a high speed that electrons jump to higher levels, then this should be discrete transitions too, or where am I wrong?
  2. jcsd
  3. Oct 22, 2011 #2


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    Science Advisor

    Ordinary light bulbs give off light from a heated wire, which acts like a black body.
  4. Oct 22, 2011 #3


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    Staff: Mentor

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