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Electric current?

  1. Aug 15, 2006 #1
    Really basic question but... why is an electric current in the opposite direction of the flow of electrons?
    Doesn't make much sense to me. :confused:
  2. jcsd
  3. Aug 15, 2006 #2


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    Staff: Mentor

    You can blame it on Benjamin Franklin. About 250 years ago he invented a "single-fluid theory" of electricity. Objects with a surplus of electric fluid were attracted to objects with a deficit of electric fluid so that when they touch they could transfer some electric fluid and even things out. He called these objects "positively charged" and "negatively charged" respectively, and electric fluid flowed from positive to negative.

    However, poor old Ben couldn't actually see the electric fluid, so he had to guess which objects were positive and which were negative, i.e. which objects had the surplus or deficit of electric fluid. But he guessed wrong! :frown:

    When electrons were discovered, people decided that it was less trouble to think of them as negatively charged, and have them flow from negative to positive, than to start calling positively-charged objects negative, and negatively-charged objects positive, and reversing the direction of electric fluid flow (elecric current) everywhere.
  4. Aug 15, 2006 #3


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    Staff Emeritus
    Science Advisor
    Gold Member

    It is a convention. You can work with either positive or negative current, it simply does not matter. The Navy taught me negative current flow, other places teach positive current flow, it really does not make any difference.....

    Other then it simply makes more sense to speak of the flow of electrons as the current.

    Yes, I am VERY aware that in ionic solutions positive ions can be the current carrier! Last I checked wires are NOT ionic solutions so that is a red herring when discussing current flow in electronic devices.
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