Electrons and color codes

Discussion in 'General Electronics Chat' started by italo, Mar 4, 2009.

  1. italo

    Thread Starter New Member

    Nov 20, 2005
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    First of all i don't think electrons know color coding but they happily flow from positive to negative leaving behind holes that of course move in the opposite direction.
    Common or grounds can be sitting at +/- 1000 of volts. So the terminology does not enply nothing except as to say things like ground is common to all our circuits or all returns are common, or all grounds are common. On a 120v ac the white is neutral while the black is considered hot and green earth. Most of house wiring follow this code but not in all of the USA it varies from county to county but all have one law no matter what color you start it better end with the same color.
     
  2. thingmaker3

    Retired Moderator

    May 16, 2005
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    I think you may have inadvertently inverted your intended implication.
     
  3. beenthere

    Retired Moderator

    Apr 20, 2004
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    This was a rather surprising find on the end of a three year old thread - http://forum.allaboutcircuits.com/showthread.php?t=2026&page=3.

    When discussing AC power distribution, holes are not common critters. They mostly reside inside semiconductors. And I think you may find the charge carriers (electrons) heading for a terminal with a more positive voltage.

    We ask, again, that posters not hijack threads. It's confusing.
     
  4. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
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    Yes, technically electricity flows from negative to positive, but as long as you have a convention of analysis and stay consistent, mathematically it can go the same direction as all the arrows on the semiconductors, making life almost as simple as vacuum tubes not so long ago. -- One of my profs.

    Ignore the above if you are a semiconductor/mask designer.
     
  5. Wendy

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    Mar 24, 2008
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    I'd rather go with reality, it's less confusing in the long run. Electricity relates to how atoms are built and their structure. Given no one subject is taught in a vacuum, things like chemistry (and don't forget electronic sensors used in chemistry), physics, and more are all interlinked, I think we'd better teach the correct conventions, and acknowledge the old conventions existed because it was so widespread and in so many old text books.
     
  6. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
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    I agree, the quote above was from an older EE Prof trying to quell the arguing over him "drawing the current the wrong way" in class. One semester, were getting both versions the same day depending on the subject.

    I apologize for the hijack.
     
  7. KL7AJ

    AAC Fanatic!

    Nov 4, 2008
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    I must have smarter electrons than most people! I can paint different stripes on a resistor, and the resistance changes automatically to match the color code. :)

    eric
     
  8. Wendy

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    And I can change those colors by increasing the voltage and making them glow!
     
  9. KL7AJ

    AAC Fanatic!

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    Yeah...they usually turn into 4 black stipes.....0 ohms! :)

    eric
     
  10. static ore

    Member

    Mar 3, 2009
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    Okay Italo and oneguy, being a rank beginner does have its drawacks, I know. However, it would be nice to resolve the context of + to - and/or - to + !!!!!!

    Oneguy, I have your desertation on the physics forum and I am working on it. However, S/ore
     
  11. PRS

    Well-Known Member

    Aug 24, 2008
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    My observation, for what it's worth: Manual and texts for beginners usually stress the negative to positive while engineering and scientific texts use the conventional positive to negative direction. Fuss and feathers, perhaps, but it must confuse the heck out of beginners who learned it one way and then run into a text that has it the other way!
     
  12. BillB3857

    Senior Member

    Feb 28, 2009
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    Therefore another anomaly...Most of mine indicate 0 Ω by color code but indicate near infinity when tested with an ohm meter.. Why is that?:rolleyes:
     
  13. b.shahvir

    Active Member

    Jan 6, 2009
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    wat KL7AJ is trying to say is that the resistor has damaged itself due to heavy amps passing thru it.
     
  14. russ_hensel

    Well-Known Member

    Jan 11, 2009
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    Current flows from plus to minus period. That says noting about the direction of elementrary particles or the fields that are equivalent to currents.
     
  15. beenthere

    Retired Moderator

    Apr 20, 2004
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    But, as electrons are the charge carriers, it's hard to imagine current as anything but negative charges moving toward a more positive point. Vacuum tube convention and Ben Franklin notwithstanding.
     
  16. thingmaker3

    Retired Moderator

    May 16, 2005
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    The definition I use has an exclamation point instead of a period. My definition is therefore more emphatic than yours. eusa_dance.gif
     
  17. russ_hensel

    Well-Known Member

    Jan 11, 2009
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    But electrons are only the most common charge carriers, any charged particle produces a current when it moves. That includes protons, for example If you wish you can call it conventional current. You must use it if you want to use Maxwell's equations as they have stood for about the last 100 years. ( I too can use extreme punctuation, but choose not to, this time. )
     
  18. thingmaker3

    Retired Moderator

    May 16, 2005
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    Demonstrate, please. Teach us the difference between amperes per square meter when using electrons and amperes per square meter when using when using holes. Show us that "J" can't work if current is defined as a flow of electrons. Pinpoint for us the change in magnitude of the curl of the magnetic field when we define "current" differently than you.

    I've got a box of chocolate-covered exclamation points for you to call your own if you succeed.
     
  19. Wendy

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    Mar 24, 2008
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    But protons don't move (other than brownian motion), the positive charge is the absence of the electron that has moved on. Unless we are talking antimatter or some other exotic situation, only the electrons move. Holes are just a concept that makes the math easier.
     
  20. russ_hensel

    Well-Known Member

    Jan 11, 2009
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    Without looking them up it is apparent that if you have a current flowing in the reverse direction and use maxwells equ to determine the magnetic field, you will need a new minus sign, or the magnetic field will be in the wrong direction. Do I need to drag out the specific equations!?
     
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