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[optics] reflection and refraction

  1. Feb 16, 2006 #1
    i have a problem with understanding the phenomenon of reflection and refraction of light.
    when considering light as a electromagnetic wave i cannot imagine how it can be reflected or refracted when meeting a surface of different refractive index. it just sounds illogical to me that sth material can affect something that is not material. the only answer i came to is that the surface creates its own electromagnetic waves and the reflected and refracted wave is really a vector addition of these two waves, but i dont think that this is a good answer.

    another thing that i dont understand is the change of speed of electromagnetic wave after crossing the surface with different refractive index. two main questions are: "why does it change" and "does it change in a infinitely small time range or is the wave beginning to brake until its speed is proper for it's new spreading material"

    when i'm considering light as a beam of fotons, the reflection and refraction doesn't leave such confusion.
    as it goes to changing the speed of fotons - i've heard that that this change is apparent, that the collisions between fotons and atoms from the surface and the reactions of absorption and emission creates this illusion of changing of the speed, which is really constant. is that true?

    sorry for any grammar&spelling mistakes
  2. jcsd
  3. Feb 16, 2006 #2


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    Read the FAQ in the General Physics sub-forum.

  4. Feb 16, 2006 #3

    Claude Bile

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    It's spelt photons, not fotons. :rolleyes: .

    Did you know that the laws of reflection and refraction arise purely from conservation of momentum and conservation of energy arguments?

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