Errors: Conventional versus electron flow

Discussion in 'Feedback and Suggestions' started by Unregistered, Feb 15, 2010.

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  1. Unregistered

    Thread Starter Guest

    This page makes several claims that are wrong, and has errors that confuse and trick new-comers.

    http://www.allaboutcircuits.com/vol_1/chpt_1/7.html

    "When Benjamin Franklin made his conjecture regarding the direction of charge flow (from the smooth wax to the rough wool), he set a precedent for electrical notation that exists to this day, despite the fact that we know electrons are the constituent units of charge, and that they are displaced from the wool to the wax -- not from the wax to the wool -- when those two substances are rubbed together. This is why electrons are said to have a negative charge: because Franklin assumed electric charge moved in the opposite direction that it actually does, and so objects he called "negative" (representing a deficiency of charge) actually have a surplus of electrons."

    Electrons have a quanta of negetive charge. They are not "the constituent units of charge". Protons also have a charge for example.

    Franklin said nothing about charge moving. He merely said that two forms of electricity seems to exist, he named one positive and one negetive. The fact that electrons moved from one to another in his particular experiment is completely irrelavant. For example if Franklin used ionic solutions instead, he could produce a negetive charged object and a positive charged object by moving only protons!

    This shows the error the author makes: Franklin simply assigned positive and negetive. He had no idea something flowed from one to the other nor which way any such flow occured. Flows can be off electrons or protons or anything else that carries a charged. Franklin did not get it wrong.

    "By the time the true direction of electron flow was discovered, the nomenclature of "positive" and "negative" had already been so well established in the scientific community that no effort was made to change it"

    Again this is so completely 100% wrong. There was no effort to change it because it was not wrong. Franklin defined negetive charge as the charge left on one material, which turned out to be due to excess electrons compared to protons, he defined the other charge as positive, which turned out to be due to excess protons compared to electrons. The 'flow' of electrons has nothing to do with it. We found that, under his definition of charge, electrons move from negetive to positive. There is nothing 'wrong' with any of this. We can also do experiments that show that positive charge flows from positive to negetive, which by the authors logic would prove Franklin right...

    The "electron flow notation" diagram is a 100% wrong. It should read "NEGETIVE electric charge moves from the negetive side of the battery to the positive side of the battery". It is 100% meaningless to talk of charge unless you specify its polarity. Electric charge by definition has a polarity which was defined by Franklin. The author seems to re-define negetive charge as positive charge and then calls this "electron flow notation".

    The 'conventional current' is not 'backwards'. Current is defined as the flow of charge. It is positive in the direction of positive moving charge. It is negetive in the direction of negetive moving charge. Thus when an electron moves one way the CURRENT flows the other way. When a proton moves one way the current flows the same way. This is by definition. It is not a mistake simply because we use the movement of electrons more than the movement of protons.

    It seems to me the author does not like the definition of current because he perfers to think about current as only electron flow (that is always negetive) rather than a flow of electric charge - which can be positive or negetive. This confusion is wide spread, and unfortuently it is helped by the fact that electron is called an electron and is thus considered to be electricity, when in reality it is no more electricity than a proton is.

    The article should focus on explaining that in a METAL charge flow happens by moving electrons - which are negetively charged. Where as in other things (such as batteries, neon signs etc) charge flow can occur by moving protons - which are positively charged. The convention is for current to move in the direction of a positive charge. So electrons flow in the opposite direction as current in metals.

    The entire rest of the books suffers the same mistake. It uses current to meant a flow in the direction that electrons move, where by definition current is the flow in the direction that positive charge moves.
     
  2. Unregistered

    Thread Starter Guest

    I would also like to point out something in:

    http://www.allaboutcircuits.com/vol_1/chpt_3/3.html "Shock current path"

    The claim is made that one side of the circuit is grounded so as to avoid shocks on one half of the circuit. This is not really true. The reason why one side is always grounded is to prevent against high voltages from existing on the circuit with respect to earth.

    A mains circuit, for example, has a 'netural' which is tied to earth simply so that the voltage between the circuit and earth does not get extremely high. For example if you have a power line with 2 wires out to a load from a generator, if nothing is grounded, the voltage between the circuit and the actual earth could be anything. If lighting strikes the line for example, both lines can be millions of volts above earth, yet the difference between the lines remains at the normal line voltage and the circuit keeps working. We earth one side of the circuit because when electricity distribution was first invented people were getting zapped without touching wires at all - because the voltage on the lines was thousand of volts above earth and when they walked past sparks arced over.

    Infact despite what this article says, it would be safer if ground was not connected at all, because two people touching ground would indeed create a ground loop, but the resistance would be twice as high as one person getting zapped. In cars chassis is grounded to save on wiring, not because it is more safer. Indeed in most electric forklifts and other industrial equipment the chassis is not connected to positive or negetive or earth. This makes it safer. As if you two people each touch each side of the battery and the chassis, the shock will be half as much as one person touching one side of the battery and the chassis.

    P.S. The earth wire comes into play because by the time they tied neutral to earth, the power lead had already been made to plug in either way - because it was AC. The problem with that is you could not know which was live and which was neutral. So if you had a chassis, the only way to ground it was to use a third wire. Which is why we have 3 pin power plugs today. This also gives the advantage of being able to compare live to neutral and make sure no current is going through earth.
     
  3. Wendy

    Moderator

    Mar 24, 2008
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    So are you claiming electrons do not move? Your 1st post strikes me as having very little merit, but feel free to register and we can discuss it in depth.

    Charge, in the form of electrons (which have mass and can be considered a form of matter), does move and it is negative. I think the way you phrased your posts is unnecessarily confrontational, no one is trying to "trick" anyone. Many concepts, when presented to people new to the subject, are usually simplified. Real understanding comes later, as the student becomes more familar with the subject.
     
    Last edited: Feb 16, 2010
  4. myforwik

    New Member

    Feb 15, 2010
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    I do not want to be confrontational, this site is perhaps the best source of electronic information for beginners that I have ever seen, I want to help :)

    I am obviously not claiming that electrons do not move. What I am saying is that electricity does not require electrons to move - it requires electric charge to move. Protons can move. Positive ions can move. The flow of electrons is not required. Electron flow is common because it happens in metals and semiconductors, but it does not happen in *EVERY* form of electricity.

    Inside a battery for example, positively charged ions flow from the positive terminal to the negetive terminal. The current is in the direction that these charges move. No electrons flow in either direction - but there is an electric current caused by the flow of the positive ions. When you connect a wire to the terminals electrons flow from the negetive terminal to the positive terminal. The current is in the direction opposite to the flow of the electrons - why? Because we have already defined current as positive in the direction of the positive charges - it cannot also be positive in the direction of negetive charges. This is the convention that the whole world accepts.

    I hope you can see that your 'correction' of Franklin is not a correction at all. You are simply making your self 'right' for flow of negetive charge and 'wrong' for flow of positive charge, completely opposite of convention. There is no reason to do this and it is bound to confuse people.

    Why not just use 'electron flow direction' in diagrams instead of calling it 'current'. It would make everything correct and consistent.

    I put this question to you:
    A bunch of + hydrogen ions flows from point A to point B. In which direction is the current? Everyone in the world will tell you that current is from A to B. But using your 'electron flow' you would say current is from B to A... why confuse the issue?

    Current is positive in the direction of moving positive charge and negetive in the direction of moving negetive charge. Its that simple. Why reverse this?
     
    Last edited: Feb 16, 2010
  5. eblc1388

    Senior Member

    Nov 28, 2008
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    Why we don't change sunrise and sunset? Well its a fact that the sun don't rise.

    Current flows from positive to negative because it is a convention we used when we first define what current is.

    The fact that electron flows from negative to positive also presents no problem or confusion in understanding by many.

    The worst culprit is to say current flows IS electron flow thus flows from negative to positive. If one wants to stick to electron flow in the sake of correctness, please make absolutely sure the flow is referred to clearly as "electron flow" and never use the term "current flow" as such.
     
  6. myforwik

    New Member

    Feb 15, 2010
    11
    0
    Yes that was the point I was hoping to make :)

    This is also why the article on static electricity has problems. For example:

    "The result of an imbalance of this "fluid" (electrons) between objects is called static electricity. It is called "static" because the displaced electrons tend to remain stationary after being moved from one insulating material to another."

    That is wrong. It describes only one type of static electricity. If someone read the article they would assume that static electricity has to involve the movement of electrons, which is not true.

    I would hope no one use the term current flow at all... is it charge that flows, not current :-D
     
  7. beenthere

    Retired Moderator

    Apr 20, 2004
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    282
    It is interesting that some people are so strongly affected by this single issue.

    We reject "conventional" current flow, as is can be demonstrated that electrons are the charge carrier in a wire, and so the charge being moved is negative. The concept of positive current in vacuum tubes was entirely incorrect, for instance.

    We try not to be overly excruciatingly correct and detailed in the Ebook, as it is at an introductory level. It is simply not necessary to be concerned about exceptions to the movement of electrons as being the general definition of current. One can always go on in the field and learn in greater detail.

    We are of course aware that the expression "current flow" is not as correct as "charge flow", but it does not seem to confuse the issue even if redundant.

    We welcome contributions by members in the framework of the Ebook material.
     
  8. Wendy

    Moderator

    Mar 24, 2008
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    A quick note how it works here. The book was started and mostly written by Tony R. Kuphaldt, who has opened it for other authors to finish and proofreading. By using a principle similar to open source (there are some differences) it is continuously being updated and proofed by people at this forum.

    I am currently one of the more active authors, but this could change. I have no real authority other than helping finish the unfinished chapters and offering updates that I may see need added. The editor, Dennis Crunkleton, looks at the various proof suggestions and articles and decides how they currently fit in the book. He is the ultimate authority.

    If you are willing to accept the site license (and put it in writing) you can write for this book. It is not a given your submission will be accepted, but if it is a reasonable offering the odds are good. There is a lot of work needing done here.

    If you find something that you think is flat out wrong, try writing a revised edition, and be prepared to accept criticism. No one is always right, and no one is always wrong. This is a public forum, and some of our members are, well, crusty. It is not a job for the thin skinned.

    Personally I welcome feedback. My background is that of a tech for almost 30 years, and I can write clearly. I have several weaknesses, so I always welcome feedback on my material. The internet usually lets me research the ideas and see if they are needed.

    If someone really hates my material (and it has happened) I usually tell them they are free to write better. So far no one has. Most people would rather dig a ditch than write, something I don't really understand.

    The moderators ride herd on the wild west types that wander in, and we get some doozies. Most are students looking for help, some are professionals (like me) willing to give help. We have everything from grunt techs, advanced students, to doctorates at this site, so it is pretty eclectic. We do have to dumb down the general chat a little, lest some of our over eager beginners see what 240VAC feels like, but other than that anything goes.
     
  9. Unregistered

    Thread Starter Guest

    Its maybe because you are using an incorrect definition of current. Current is the flow of positive charges - not electrons.

    The problem with using movement of electrons as current is that it does not support the most basic maths. If you have a 1 ohm resistor and 1amp of electrons flow from A to B though the resistor, then V=IR says that 1A*1Ohm=1V. Therefore there is 1 volt from A to B, which is of course wrong, there is -1V from A to B because current flows from A to B not B to A.

    This isn't just a issue with convention. Its an issue because it is totally incorrect and does not allow a person to flow on to proper/continued education. Anyone who wanted to learn more would then have to unlearn that current is a flow of electrons and learn that current is flow of positive charge or that the inverse of current is the flow of electrons.

    Hopefully I can contribute some changes, but english is not my first language and usually i am not good at explaining :-D
     
  10. Wendy

    Moderator

    Mar 24, 2008
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    You need to look at an atom, it is electrons that do the moving, which are negative. In a wire it is the negative charge that is moving, not the positive. Basically you are talking conventional flow, which is the wrong concept when talking flow and has been rejected by this text book, with explinations.

    If you wish to discuss this you must register, this forum is for feedback of the book.
     
    Last edited: Feb 17, 2010
  11. beenthere

    Retired Moderator

    Apr 20, 2004
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    This is simply not going anywhere. The electron is the charge carrier in wires, and carries a negative charge. That has been demonstrated with the original series of experiments that established the magnitude of the charge of the electron.

    The OP may register, and continue this thread. But he is strongly advised to be able to cite material that supports his contention.
     
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