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Conventional Current

  1. Dec 30, 2013 #1
    I know that conventional current is when the electrons flow from cathode to anode but I was wondering if there is any difference in solving a circuit for its voltage resistance current capacitance etc.. with non conventional current do you get a difference answer and do engineers ever use non conventional current?
     
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  3. Dec 30, 2013 #2

    phinds

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    I don't know what you mean by "non conventional current". It is irrelevant what direction you assign to a current when you are solving a circuit problem since if you have assigned the "wrong" direction, you just get a negative answer.
     
  4. Dec 30, 2013 #3

    Drakkith

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    I thought "conventional" current was from positive to negative.
     
  5. Dec 30, 2013 #4

    AlephZero

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    That is a very limited idea of what "current" is. In most materials except for metals, (for example sparks in air or current in living creatures, electronic components, batteries, etc) current is NOT necessarily "the flow of electrons" at all. There may be both positive and negatively charged particles, moving in opposite directions.

    To analyze electrical circuits, using "conventional current" flowing from positive to negative voltage allows you to ignore all those complications, and also to ignore the electrons.

    If engineers need to understand how components like transistors or batteries work, as opposed to understanding how to use them, then they need to look at all the details of the physics, and that may involve quantum mechanics rather than the simplified idea of "charged particles moving about".
     
  6. Dec 30, 2013 #5
    Semiconductors can have positive charge carriers called holes. The circuit law equations are no different. Holes carry positive charge from the cathode to the anode and electrons carry charge from the anode to the cathode. Because they have opposite charge they both produce current in the same direction even though they move in opposite directions.

    I suppose the same would be true for currents made by positive and negative ions in water.

    You made a mistake, btw. Electrons flow from anode to cathode (negative to positive). Current flows from positive to negative. Electrons flow in the opposite direction of the current you see in circuit equations (if you follow convention).
     
    Last edited: Dec 30, 2013
  7. Dec 30, 2013 #6

    davenn

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    yeah me too ( ie not electron flow)

    Dave
     
  8. Dec 30, 2013 #7
    So what particle is flowing in a circuit when there is current. I know that electrons go from negative to positive but what goes from positive to negatie in a circuit is a positron but I am pretty sure that antimatter does not take place. I usually use current in terms of circuit what do you mean that current can be something else besides an electron.
     
  9. Dec 31, 2013 #8

    davenn

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    its the electrons that are "flowing" so there is a charge moving from negative to positive

    this is used because its the "free" valence electrons in a conductor that are able to move

    Dave
     
  10. Dec 31, 2013 #9

    CWatters

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    When an electron breaks loose from an atom and becomes free it leaves behind a "hole" which is an atom with a net positive charge. That hole will accept other electrons from other atoms and so the hole or positive charge moves about. The atom itself doesn't move but the net positive charge does. Mainly important in semiconductors.
     
  11. Dec 31, 2013 #10

    sophiecentaur

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    If you try to use 'electrons' in circuit calculations, you will fall on your face before long. Likewise, if you use 'electrons' to explain what happens in electrolytic cells. The whole point about dealing with electrical problems using Current is that it doesn't matter what is carrying the charge. It is not a cop out to use Current. It is not 'wrong'. It just makes sense and avoids all those misunderstandings that people have when they try to use a half understood picture of an electron and try to apply it to a problem that's too complex. You may as well say that someone is not doing it properly when they use algebra / calculus / trig functions, which are half way along the path between numbers and physical results.

    Can you find any instance of a textbook that uses electrons when "solving a circuit"? Why do you think that is?
     
  12. Dec 31, 2013 #11
    Is the electron hole the thing that moves from positive to negative? I know electrons travel through these empty electron shells because they are attracted by its lack of a negative charge, making it have a positive charge relative to the other electrons.
     
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