Theory Question - Electron Flow

Discussion in 'General Electronics Chat' started by NzWiztek, Aug 18, 2014.

  1. NzWiztek

    Thread Starter New Member

    Aug 17, 2014
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    Hi Guys,

    Just something I'm curious about and I know it makes little difference for circuits apart from vacuum tubes.

    I want to be able to visualise the current flow correctly, and from what I have seen good old Franklin got the direction wrong.

    So what I can't get my head around, if the more positive terminal has a deficit of electrons, why do we get the shock off the positive side of a circuit?

    Actually typing that out, I may have just answered my question.. We don't get the shock off the positive, we are just completing the circuit...?

    Thanks

    Mike
     
  2. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    Correct.

    Positive to negative flow is the flow of holes that most people will consider 'normal'.

    Electron flow from negative to positive is what actually happens.
     
  3. MikeML

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    You are just as likely to feel a shock if touching -100V as +100V. The cells in your finger do not care which way the electrons are swimming :D
     
  4. bwilliams60

    Active Member

    Nov 18, 2012
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    Do holes flow? An atom stays in place, electrons move, holes are left behind. Electrons move to fill holes.
    Conventional Theory - outdated
    Electron Theory - Stands to Reason
    Hole Theory - Two drunk guys at two in the morning solving the worlds problems and recreating what is already known.
     
  5. alfacliff

    Well-Known Member

    Dec 13, 2013
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    do holes flow? yes and they can be stored too, just look at the streets in wichita, lots of holes.
     
  6. GopherT

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    Your view of holes is like saying "it is completely wrong to think that a bubble flows to the surface in an aquarium, the water around it pushes it up".

    From my trained eye, since all of the electrons look alike and there are so many of them, when one jumps to the right to fill a hole, it appears as though the hole moved to the left. Therefore, like bubbles rise to the surface, holes appear to flow.
     
    Last edited: Aug 19, 2014
  7. ErnieM

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    Apr 24, 2011
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    Anyone who believes that conventional current flow is incorrect or outdated while electron flow is the reasoned approach understands neither.
     
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  8. studiot

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    Nov 9, 2007
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    Agreed.

    Most electric devices these days contain a battery.

    Which way do charges 'flow' inside the battery?

    And are they only electrons?
     
  9. MikeML

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    In a former life, I fixed ion-implant machines used in Integrated Circuit fabrication.

    The machine is basically a 10m pipe with a non-perfect vacuum inside. There is a huge voltage difference between the ends of the pipe (100KV). Inside the pipe, free electrons are accelerated by the large electric field. They bash into gas molecules, knocking loose another electrons (thereby ionizing the gas molecule, giving it a positive charge).

    Now we have positive ions of Nitrogen, Oxygen, and others, being accelerated in a direction opposite to the way the electrons are moving.

    If you measure the current flowing down the pipe, you will find that the total current is the sum of the negative charge being carried by free electrons going in one direction plus the positive charge being carried in the opposite direction by the ionized molecules (missing one, two, or three electrons).

    So electrons move one way while holes move in the other. Both contribute to the current as measured with an ammeter on the high voltage power supply.

    Now read my signature line...;)
     
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  10. BR-549

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    Sep 22, 2013
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    I don’t believe either of the theories of current. Hole or electron flow. I believe free electron flow is responsible for skin effect and the capacitance and inductance that opposes current in a conductor. At very cold temps....there is no free electrons and no skin effect. Therefore at very low temps....no reactance to flow.
    I believe there are two parts to resistance. I believe electrons only line up for current to flow, they only turn, they do not change location. When electrons are warm....they wobble. The more they wobble.....the harder and more voltage is needed to keep them lined up. At low temps....almost all the wobble is gone. At this time all we have to deal with is the atomic structure resistance. Some elements take a lot of voltage to make the electrons turn, and other elements, not so much. This is material resistance. So if we get rid of the skin effect and the wobble.....we can see what real conduction is without any interference. Electrons not only have charge....each has a magnetic north and south pole. When a voltage lines up the electrons....it also lines up all those magnetic moments. This allows magnetic flux lines flow longitudinally thru the conductor. These lines have force and can do work. This is electric current.
     
  11. NzWiztek

    Thread Starter New Member

    Aug 17, 2014
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    Does someone have a good resource to enable me to "understand" both?

    Most books barely touch this issue.

    Thanks
     
  12. studiot

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    Did you look at a complete circuit and attempt to answer my question about a battery?

    The choice of mathematical direction is entirely a matter of convention since.

    1) There are both polarities of current carriers in any conductor, although sometimes one predominates as with electrons in metals. But ions in chemical solution may be different and how about the movement of electrons in corrosion currents or plasma currents in striplights?

    2) Much of circuit analysis is formalistic and one takes an assumed current which may not actually exist, for example Maxwells Mesh Method.

    3) Direction is irrelevent in AC anyway.

    4) The direction of 'conventional current' is consistent with a whole raft of equations and theory in other aspects of physics eg Flemings Rules, Lorenz Force Law, Feynman Diagrams.
     
  13. bwilliams60

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    Nov 18, 2012
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    Wow, I guess I struck a nerve. I work with batteries all day long, every day so I use the conventional theory. I have been taught that electron theory is more correct and I tend to agree. It seems that membership here has many different viewpoints as well. For something seemingly simple, we really do complicate things. And yes, I do understand the two theories I mentioned.
     
  14. studiot

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    Hello Brian (is it Brian?)

    Look at any complete loop and mark two points A and B along the loop.

    Call these the battery (or other source) terminals.

    Now allow current to flow around the complete loop.

    If the current flows from A to B the long way round which way will it flow the short way?
     
  15. BR-549

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    Sep 22, 2013
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    No. There is no text for my theory. Most everyone believes charge movement is current. If your question is for homework or a course, or class, please disregard my comments. If you even mention my theories in class or on your work......you will likely be thrown out of class. I have lots of experience on that. When people first started playing with electricity.....they used tubes. Now a tube is truly a electron movement device. It uses the skin effect electrons to transfer charge from one circuit(or conductor) to another. This is probably why they thought electrons flow thru wires. I doubt very seriously that electrons flow thru wires. My theory also explains some of a superconductors properties. I didn't mean to confuse you. This is general chat.
     
  16. studiot

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    BR-549

    I have disagreed with some of your more outlandish theories in the past, but there is much truth in what you say here so electrons do not actually travel from say the Redbud Dam to Memphis.

    But that is the Physics of the situation.

    This is the electronics part of the forum and here we are talking about circuit models, where it is convenient to calculate as though they did.
    Or at least a mythical 'current' travels this path to supply power.
    Just as it is convenient to regard this current as a sort of fluid for calculation purposes.
     
  17. BR-549

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    Sep 22, 2013
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    Ok...just one last question. When a electron drops in a hole anywhere else in physics, what happens? Where did the light go?
     
  18. studiot

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    Well pair production requires the passage of particularly energetic gamma rays and pair annihilation (drops in a hole?) produces the same.
     
  19. BR-549

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    Sep 22, 2013
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    We have to heat a light filament very high to get it to emit an electron cloud. Then when the electron refills a vacant hole, we get the light. If hole conduction is true(and then electron movement), ...Edison would have been done in an hour.
     
  20. studiot

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    What makes you think are are any 'holes' in a light bulb filament?
     
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