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How do classical and quantum mesh?

  1. May 10, 2008 #1
    I have a question for the enlightened minds.

    In physics class we found our debrouille (sp?) wavelength, we found that an average human gives a ridiculously small wavelength. H/p. Now what happens when you do this to an electric current in an exposed wire? (6.626E(-34) m2 kg / s)/(9.11E(-31)*(0.0002 m/s) (the speed electrons flow in a wire, but this can be changed). But that gives you a wavelength of 36.3215m and a frequency of 8.2369 MHz. This is pretty close to the RF of remote control cars, and in between AM/FM frequencies. Would there be a way to this up through a tuner of some sort? Or is this how the technology behind radio transmissions works?
  2. jcsd
  3. May 10, 2008 #2
    de Broglie, which is roughly pronounced the way you spelled it.

    The waves you are referring to are classical electromagnetic waves, not matter waves. The electrons in traveling in a current exhibit two types of velocities, one being their own, individual velocity, and the other being their drift velocity. Basically electrons scatter off of impurities and other electrons in a metal, so even though they are going rediculously fast, their average displacement ends up being very small (that's the drift velocity).

    I think that if you did the calculation with their true velocity (in between scattering) then you would get a de Broglie wavelength that is much much smaller.
  4. May 10, 2008 #3


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    Actually, I believe its pronounced "debroy".
  5. May 10, 2008 #4
    True, I meant the way he spelled it, not I =)
    But yes, that is the proper rendition.
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