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Positive/Negative Symbol Confusion

  1. Jul 15, 2012 #1
    So since we know that electrons are flowing in a relatively less negative (relative positive) direction why does + indicate source? Surely the electrons are flowing towards the + and not from it.
  2. jcsd
  3. Jul 15, 2012 #2


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    Conventions in electronics were set before anyone understood electrons. Get used to it.
  4. Jul 15, 2012 #3
    Could do with fixing then.
  5. Jul 15, 2012 #4


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    Yeah, well good luck with that. Do you think you're the first person to have noticed the problem?
  6. Jul 15, 2012 #5
    I suggest forward progress should include revision as well as innovation. If you think changing symbols on electronics is too lofty a goal perhaps you could focus on something more manageable like doing the laundry and/or taking out the trash.
  7. Jul 15, 2012 #6
    Keep it civil man. phinds is a very knowledgeable and helpful fellow.
  8. Jul 15, 2012 #7


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    Your assumption that "current = a flow of electrons" is often wrong. It happens to be right in metals, but it's wrong for many electronic components (not only for semicondictors, but also electrolytic capacitors, batteries, CFL lamps, etc, etc).

    It is also wrong for most "natural" current flows in the earth, its atmosphere, water, living organisms, etc.

    So your idea that swapping "+" and "-" somehow fixes a problem doesn't work too well.
  9. Jul 15, 2012 #8
    You guys are very close to be labeled damaged goods. If you want to throw around morality start with the guy you're protecting. I'm tired of passive-aggression in all its forms and those stupid enough to protect it. I have the right to stand up for myself and just because he isn't being ugly in an overt way does not make it any less ugly. Grow up the both of you.
  10. Jul 15, 2012 #9
    I find it terribly annoying that you would correct me but then not give any backing explanation for your statement. So I'm wrong. What is the more correct understanding/statement? If you would correct someone be prepared to offer them an explanation that they can then use in the future.
  11. Jul 16, 2012 #10
    The rules of these forums state that explanations should be in line with accepted knowledge. Most of this is backed up in countless text books.
    There is nothing 'wrong' with the way + and - is used. It is a convention.
    First of all you should check text books for an explanation.
  12. Jul 16, 2012 #11
    If you weren't in such hurry to be an idiot you might have noticed that the explanation to the most asked (and answered) question in all of electronics was in the very post you responded to (that would be post #7).

    You can also check out this: http://en.wikipedia.org/wiki/Electric_current#Conventions
    Last edited: Jul 16, 2012
  13. Jul 16, 2012 #12


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    You obviously leapt into this thread, spoiling for a fight, which is a shame. The fact is that there is no problem whatever 'sign' you choose for describing current. The actual mechanism of carrying charges is just not relevant and a preoccupation with what goes on in metals is just too parochial. If you want to get an understanding of this then just follow 'the rules' and it all works.
    If you really think that the reason for not changing is just that Scientists are brainless and conservative then you have a lot to learn. Just because you are confused, don't assume that 'we' are all wrong.
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