millman theorem article confusion

Discussion in 'General Electronics Chat' started by Akshay Nagar, Sep 26, 2015.

  1. Akshay Nagar

    Thread Starter New Member

    Sep 26, 2015
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  2. crutschow

    Expert

    Mar 14, 2008
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    I believe that tutorial uses electron flow (negative to positive) in all their calculations.
    That's opposite of the conventional current flow, which is positive to negative.
     
  3. dl324

    Distinguished Member

    Mar 30, 2015
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    Welcome to AAC!

    I recall reading that all of the tutorials use electron current flow rather than conventional.
     
  4. #12

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    Nov 30, 2010
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    Just remember, the definition of, "convention" is, "an agreement among people".
    There are people that argue one or the other direction with the fervor of a rabid dog. The only part that matters to the beginner is to be consistent within any one circuit you are trying to analyze. Pick one and stick to it, at least until you get to the next problem.
     
    atferrari likes this.
  5. WBahn

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    Mar 31, 2012
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    The primary E-book author decreed that the E-book would use "electron current" instead of "conventional current". In my opinion, this is very unfortunate. As long as you are aware of this, you can usually work with the material in the E-book (you can always just draw your own sketches and translate things to conventional current when you are thinking about them).

    Note that most people that favor "electron current" do it wrong -- they want to pretend that positive charge is flowing in the same direction as the electrons are flowing, but they don't want to reverse the polarity of voltages in order to be consistent with this pretention. So they end up throwing magical mystery minus signs at things from time to time. Fortunately, most of the places where this has to be done are pretty obvious and most people apply them without even thinking about them -- but this has the unfortunate side effect of not making it obvious to them just how inconsistent they are actually being.
     
  6. #12

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    I usually just ignore the arguments and feel grateful that I can think in either direction. Maybe now I have a clue about one fallacy I had never heard of before.
     
  7. vk6zgo

    Active Member

    Jul 21, 2012
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    The only people who want to put "magical mystery minus signs" into things are the "Conventional
    Current Flow" people when,in a religious fervour,they try to prove the unprovable.

    It doesn't matter if current flows +ve to -ve,or "Electron Flow" goes the other way,voltage drops around a circuit will appear exactly the same.

    Many years back,it took about 5 minutes for an "Elementary Electrical Theory" class to understand that both
    were interchangeable.

    Electron Flow helps to understand such things as Thermionic tubes,& Conventional Current Flow is better for the application of things like "Right Hand Rules" & the like.
     
  8. dl324

    Distinguished Member

    Mar 30, 2015
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    Quote from an OSU lecture:
    In 1752, prior to electricity being identified with the electron, Ben Franklin chose a convention regarding the direction of current flow. Franklin assumed that electrons (being assumed positive) flow from positive to negative terminals. We now know this is incorrect. The charge on an electron is negative by definition (note negative sign): (-1.6x10-19 C)

    The flow of electrons is termed electron current. Electrons flow from the negative terminal to the positive. Conventional current or simply current, behaves as if positive charge carriers cause current flow. Conventional current flows from the positive terminal to the negative. Perhaps the clearest way to think about this is to pretend as if movement of positive charge carriers constituted current flow.

    The lecture ends by saying that Conventional current flow is the standard that most all of the world follows.

    All of my text books use conventional current as do all databooks and datasheets I have...
     
  9. WBahn

    Moderator

    Mar 31, 2012
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    Okay, so if you want to claim that using electron flow doesn't involve any magical mystery minus signs, then answer the following question without resorting to one.

    A current of 1A is flowing from left to right (again, using electron current) between two initially uncharged objects. After one second, what is the next charge on each object. Keep in mind that an ampere is defined as a flow of one coulomb per second.
     
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