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Zero to Light Speed - Atom's Point of View

  1. Aug 25, 2004 #1
    [SOLVED] Zero to Light Speed - Atom's Point of View

    Atoms in a light bulb filament with house current are heated to the point that they readily emit visible light photons.
    Three Questions:
    1. What is the expected (or virtual) speed of the ELECTRON that emits a photon just as that photon is escaping from the immediate vicinity of the atom that generated that photon?
    2. What is the expected (or virtual) speed of a PHOTON as it escapes from the immediate vicinity of the atom that generated that photon?
    3. If the photon is accelerated over this atomic-level distance, then what is causing the acceleration?
     
    Last edited by a moderator: Aug 25, 2004
  2. jcsd
  3. Aug 25, 2004 #2

    chroot

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    1. The average velocity of an electron in a conductor is on the order of a hundred thousand meters per second.

    2. The photon always travels at c.

    3. The photon does not accelerate. It was travelling at c the instant it came into existence.

    You seem to think of the emission of a photon as a sort of "launching" event by which a "piece" of the electron is thrust off as a photon. This is not accurate.

    - Warren
     
  4. Aug 25, 2004 #3

    mathman

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    In a light bulb, the electrons (current) heat up the wire. The wire then glows because it is hot. At an atomic level, the photons come from energy transitions of the electrons within the atoms, not specifically the current.
     
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