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Spinning probabilities

  1. May 6, 2010 #1
    In the Richard Feynman book QCD, he talks of the chance of reflection of a light photon off water varies from 0% to 8% (depending on the width of the layer). He says that the probability changes 36000 times per inch for red light without showing how it is done (ie. how he got the 36000 rotations per inch for red light) (page 27)

    I may have missed something simple, but how do I calculate this? (ie, how many times does blue light rotate after travelling an inch)?

  2. jcsd
  3. May 7, 2010 #2


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    Simply the number of wavelengths per inch.
    1 inch ~= 0.0254 m, and red light is ~700 nm so 0.0254/700E-9 ~= 36000.
  4. May 7, 2010 #3
    Last edited by a moderator: Apr 25, 2017
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