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Absorption and reflectance spectrums

  1. Jun 28, 2008 #1

    just wondering, what's the relationship between absorption and emissions spectra (i.e. would they absorb and reflect the same wavelengths or complement wavelengths of radiation?)


  2. jcsd
  3. Jun 28, 2008 #2


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    Light that strikes an object is either:
    1. Absorbed
    2. Reflected
    3. Transmitted

    These must all add up to 100%:

    A + R + T = 100%

    For opaque objects, T=0 (no transmission) and the equation simplifies somewhat.
  4. Jun 28, 2008 #3


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    For a particular substance, they are the same. It depends on the temperature of the medium relative to the light coming through. Hotter leads to emission, colder leads to absorption.
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