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Why do black bodies emit light at all wavelengths when heated?

  1. Feb 23, 2010 #1
    Why do "black bodies" emit light at all wavelengths when heated?

    Light emitted from an object is made of photons that are emitted when electrons drop into lower energy states. And there are only certain energy states in an atom that electrons can occupy, so only certain wavelengths (aka. energies) of light are produced by specific atoms.
    This is why the emission spectrum of elements is characterized by discrete lines at specific wavelengths.

    However, black bodies have a continuous emission spectra. Why are black bodies different --- do they not have finite electron energy levels?

    Thank you. This is my first post. I'm glad to be on here! :)
  2. jcsd
  3. Feb 23, 2010 #2


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    Re: Why do "black bodies" emit light at all wavelengths when heated?

    Thermal emission is different from the stimulated emission you described.
    In a thermal source the charged particles are moving because of the thermal energy, moving (or at least accelerating) charges emit light
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