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Electron flow and direction

  1. Dec 27, 2009 #1
    Hello gurus!

    I have a novice question. I hope you don't mind me asking this question as it most likely is a very basic question to many.

    Electrons flow from -ve to the +ve side of a battery.
    Why then do people also say electricity flows from the +ve to the -ve end?
    I recall being told the reason many years ago but have forgotten why.
    Could you kindly help to expain a bit?

    Thanks! :)

  2. jcsd
  3. Dec 27, 2009 #2


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    Hello Ramone! :smile:
    It's because they decided on +ve and -ve a long time before the electron was discovered, and then they couldn't be bothered to change it. :wink:

    See http://en.wikipedia.org/wiki/Electric_charge#History" for some details.
    Last edited by a moderator: Apr 24, 2017
  4. Dec 27, 2009 #3


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    By convention the current is equivalent to the movement of + charges, or opposite the motion of negative charges. Before the electron was discovered people thought there were + and - charges, rather than the + charge simply being the absence of electrons.

    In a battery a chemical reaction cause the electrons to be attracted to the negative terminal. When placing a short circuit or conductor across the termials, this allows the electrons to flow through the conductor.

    In generators, the electrons are moved by time varying or moving magnetic fields.
  5. Dec 27, 2009 #4
    In addition to the above wiki reference, read about Volta, who developed the first battery (pile) ~1800.
    If Volta had piled copper on top of zinc, rather than zinc on copper, perhaps the current convention would have been different.
    Bob S
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