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Circuit question

  1. Sep 14, 2011 #1
    I'm just wondering if current can go in two opposite directions. To clarify, I'm thinking about a simple circuit. Say you construct a circuit with two loops, both of which original from the same terminal of a battery, on loop which goes to the left and the other which goes to the right, and then both loops connect at some node and combine to go to the other terminal of the battery.

    I figure that in order for the current to flow from on terminal to the other, there is only one path path it can take (that center path where the two loops combine), but in order for the currents to get there one current would be clockwise whereas the other would be counterclockwise (because on loops goes to the left the other goes to the right).

    I would provide a picture of what I'm picturing but I'm on my phone. Perhaps I will take a picture with my phone and upload it later.

    Any help would be much appreciated.
     
  2. jcsd
  3. Sep 14, 2011 #2

    phinds

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    Perhaps I'm missing what you are saying, but if I DO understand what you are saying, then you are just confusing yourself by the particular way you have decided to draw the circuit and there is no real issue. If you don't think this is the case, post a diagram of what you ARE talking about.
     
  4. Sep 14, 2011 #3
    Ill get a picture up. It mist likely won't be a proper wiring diagram, not the actually apparatus (since I currently don't have resistors or a battery or wire or anything of the like, but ill get a picture up nonetheless. Just wait a few minutes

    EDIT: apparently I can't upload a picture through the mobile site, so it will be an hour before I get it up. Sorry =/
     
    Last edited: Sep 14, 2011
  5. Sep 14, 2011 #4
    Should you check Kirchoff's Law re current flow in a circuit?
     
  6. Sep 14, 2011 #5
    One type of charge carrier goes only in one direction in a given circuit....clockwise and counterclockise means nothing to thee charge carriers. Just flip one loop from side of your diagram to the other and you'll see that actually move in the same direction....But if you have electrons and holes in the same circuit, they do move oppositely because they are of opposite charge.
     
  7. Sep 14, 2011 #6
    Well that's why I figure postive terminal to negative terminal counts as one direction, but what if there are two paths to get there, one of which is clockwise, the other counterclockwise.

    I have attached two pictures, one of what the setup would be like, and one of the circuit diagram. I realize that the circuit diagram is simple - I understand that current through that. What I am wondering though is:

    Say that the current flows from the negative terminal to the positive terminal (if you want it to get from pos to neg then reverse the circuit), and that there is a wire or a load resistor or load resistor or SOMETHING that is between terminals A and B in order to complete the circuit (so I am talking about a CLOSED CIRCUIT. I Realize that I drew an open circuit). Could one current go through R3, then through whatever connects terminals A+B, and then go through R2 in order to reach the positive terminal, while another current goes through R1, then takes R2 in order to reach the positive terminal?

    because if that doesn't happen, and all the current started out going through R1, then split at terminal A to go through R2 and R3, the current through R3 would simply return to the negative terminal, which wouldn't make sense because there would be no potential difference, would there...?

    And yes, I realize that if I say that the current goes from positive to negative that it would simply go through R2, split at terminal A (because there is a load resistor or wire or something connected between the terminals), and then end up at the negative terminal. That is not what I am asking though.
     

    Attached Files:

  8. Sep 14, 2011 #7
    I'm not looking at any diagrams..sorry but your question in non sensical as I described....if you look at you pictures from the back of the page the direction is again reversed...so what??

    If you want to believe that electrons flow in a direction other than from a negative terminal to a postive terminal in a circuit...despite all evidence to the contray, go right ahead. good luck
     
  9. Sep 14, 2011 #8
    i never said that they go in a different direction then negative to postitive. I'm saying if one loop from the negative to positive terminal is clockwise, and the other is counterclockwise, would you have electrons going clockwise and electrons going counterclockwise? They are still going negative to positive, but the paths they take to get there is different.

    As to your earlier post, if i flip the ccw loop it will become cw, and then there is no confusion, so thank you. The source of my confusion, however, was that in a real life circuit i cannot just "flip the loop", which is why I was confused. On paper it is clear.

    Thank you.
     
  10. Sep 14, 2011 #9

    phinds

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    I have to agree w/ Naty and my original post. You are confusing yourself with terminology. Your "problem" is meaningless. "clockwise" and "counterclockwise" are terms of your own devising in this context and have no relevance the the circuit. The electrons just don't care how you choose to describe the circuit, they just go right on obeying well-known and well-understood (but not yet by you) laws.
     
  11. Sep 14, 2011 #10
    Yeah, I confused myself and I got it all sorted out. It wasn't the drawing that confused me though, I'm alright with circuit diagrams. It was looking at the actual circuit that confused me because by thinking in terms of cw and ccw it appeared to me like the currents would be opposing, but thinking in terms of negative to positive terminal it makes perfect sense.
     
  12. Sep 14, 2011 #11
    As you know already flow always goes negative to positive, As others pointed out counter clockwise and clockwise are impractical terms on electron flow, keep in mind however that potentiometers do use those terms on their posts. Those terms however are only used to describe which pin increases in resistance according to which way you turn the potentiometer. Also some books will mention the flow of charge (not electron Flow) as positive to negative flow.
     
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