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Frequency and absorption

  1. Oct 27, 2008 #1
    Hi, recently I've been doing some experiments on how and if frequency would affect the amount of energy lost by light as it passes through glass. So far, I've had some rather erratic results. Can someone clarify for me whether frequency does affect the energy drop of light passing through glass and how? So far from what I've understood, photons are absorbed and re-emitted. The absorption of the photons depends on the individual absorption spectrum of the material in question. Once its absorbed though, higher energy photons tend to take longer to be re-emitted and so re-emission happens slower for higher frequencies, thus some energy would be left in the glass for awhile? Can someone confirm whether frequency has any effect at all and how it affects the % of energy lost?

    Btw, this is not homework, experiment done outside of school.
  2. jcsd
  3. Oct 27, 2008 #2


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    Absorbed light (usually) goes into heating the glass. Heated glass radiates energy, so you can think of the absorbed light as being converted to whatever wavelengths are radiated.

    The radiated wavelengths depend on how hot the glass gets. Near room temperature they are mostly in the range 5 to 20 microns.
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