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Homework Help: What's the difference between emission and absorption?

  1. May 26, 2010 #1
    My textbook says "absorption yields color. emission yields fluorescence" - can someone explain what that means exactly.

    I know color is when something absorbs all wavelengths except one, which gets reflected and produces color.

    If it helps... the chapter is on bohr's model.
  2. jcsd
  3. May 27, 2010 #2


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    Sounds like you've got a good handle on absorption already.

    For emission, think about how black-light posters work (or anything with fluorescent paint put under a black-light). The original light is at such a high frequency (small wavelength) that one can't see it (or just barely see it), and for practical purposes you can consider it to be a single wavelength. Yet the bright paint is easily visible, at easily visible wavelengths. So there has to be something more than absorption going on. :wink:
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