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Electric Current in an open circuit

  1. Dec 27, 2013 #1
    I'm still a beginner at Electricity and electromagnetism, I'm wondering If we connect a wire to a positive terminal ONLY , why won't the electrons flow to the positive terminal of the cell as electrons are negatively charged, I have been days thinking about it and I need a clear convincing answer I don't matter if it is in detail but I need an understandable answer for a beginner
     
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  3. Dec 27, 2013 #2

    TumblingDice

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    Why wouldn't they? (as long as there's nothing wrong with the wire)
     
  4. Dec 27, 2013 #3
    So there would be an instantaneous current in the wire?
     
  5. Dec 28, 2013 #4

    Student100

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    In chemical batteries the electrolyte prevents electrons from going up from the anode to the cathode. It would be kind of pointless to have a battery that constantly was reacting without a circuit.

    Well hopefully they wouldn't, seeing as how he hasn't completed the circuit.
     
  6. Dec 28, 2013 #5
    But the electrons would move towards the anode the they would stop? I mean some kind of an instantaneous current
     
  7. Dec 28, 2013 #6
    Then they would stop *********
     
  8. Dec 28, 2013 #7

    Student100

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    Current flows from the anode to the cathode, a wire connected on the cathode only wouldn't permit the chemical reaction to occur. As I said before, the electrolyte prevents stray elections from going anode -> cathode.

    This is an over simplistic view on batteries in general, but I’m not sure how much you actually understand.

    So no, no instantaneous or inrush current that I’m aware of, but I have a very superficial understanding of batteries in general.
     
  9. Dec 28, 2013 #8

    I'm talking about a wire connected to the anode not to the cathode
     
  10. Dec 28, 2013 #9

    Student100

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    Then edit your question, the anode is the negative terminal.
     
  11. Dec 28, 2013 #10
    I'm a little bit confused I'm so sorry, I know the fact that chemical reactions won't occur in an open circuit but I mean why won't the electrons move toward the cathode "as electrons are negatively charged" then just stop there till the circuit is closed
     
  12. Dec 28, 2013 #11

    Student100

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    Like I said, there is “stuff”(electrolyte) inside the battery that prevents electrons from moving inside the battery itself.

    If you just had a wire on either the anode or cathode you have an open circuit. V=I/R, which means voltage equals current divided by resistance, think about the resistance of air for a moment. The wire hanging off either creates a potential if the circuit is completed, but cant do any work itself. What you’re basically doing is creating “pipe", but no “water" (current) will flow because you haven't built your infrastructure up completely. So there is a potential for electrons to flow, but you need a completed circuit.

    I’m not trying to be short with you, so no need to apologize, hopefully someone will respond with a better way to explain things then I can come up.
     
  13. Dec 28, 2013 #12

    Who said that you are trying to be short???!!! I never thought of that I actually appreciate your replies,, thanks very much
     
  14. Dec 28, 2013 #13

    davenn

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    sorry, wrong answer!!

    correct answer, no circuit completed, therefore no current will flow .... simple as that
    doesnt matter which terminal of the battery or power supply the single wire is ONLY connected to.
    If there uis no circuit between the positive and negative terminals, then no current flow

    Dave
     
    Last edited: Dec 28, 2013
  15. Dec 28, 2013 #14

    Yes. Some electrons move to the anode, stop there, and neutralize the anode.
     
  16. Dec 28, 2013 #15
    !!!! I'm confused I got 2 different answers to the same post
     
  17. Dec 28, 2013 #16
    I Need to talk someone specialized in electric physics or engineering
     
  18. Dec 28, 2013 #17
    Here is a AC generator and an open circuit:

    O------------G--------------O

    O is a metal ball. G is the generator.

    A current will flow in that open circuit.

    In an open circuit there will be no continuous DC current.


    AC=Alternating current
    DC=Direct current
     
    Last edited: Dec 28, 2013
  19. Dec 28, 2013 #18
    I don't get your point, let's talk about a normal battery and a circuit will there be an instantaneous DC if it is connected to Positive terminal only
     
  20. Dec 28, 2013 #19

    davenn

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    No



    Dave
     
  21. Dec 28, 2013 #20
    Yes. A momentarily DC current.
     
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