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Derivation of De Broglie wavelength

  1. Oct 26, 2005 #1
    The De Broglie wavelength was derived like this by our physics teacher.
    E=hf v=fλ E=mc^2
    Then the WRONG BIT

    But that only works for light (when c=v). There must be a correct way of deriving it for electrons etc. We are expected to use this for electrons.
  2. jcsd
  3. Oct 26, 2005 #2

    Hans de Vries

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    It only works if you take: wave-speed = [itex]\frac{c^2}{v}[/tex] where v is the physical
    speed of the electron, this is however an ad-hoc assumption here. It's not
    that hard to derive λ=h/ρ directly from E=hf but it takes Special Relativity:


    Regards, Hans
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