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Why does current flow the opposite way from the electrons?

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Re: Why does current flow the opposite way from the electrons?

#101

Post by bmacho »

LgWoodenBadger wrote: post #23
crazygringo wrote: post #21

Earlier quoted context omitted.

> So you shouldn't say "electron is negative". That's weird, confusing, misleading, and trolling. Huh? By the convention you describe (and we all share), electrons have negative charge, since -1 is negative. When speaking in the shared and understood context of charge, you shorten that to saying electrons are negative. Nothing weird, confusing, or misleading, and certainly not trolling. I'm baffled where you get that…

He comes from an accounting background where commonly-understood terms mean the opposite of what everyone commonly understands them to mean.

I am not sure what this means? Is this pure lies and insults? I don't see anything else here? In that case, fuck you very much :shrug:

Re: Why does current flow the opposite way from the electrons?

#102

Post by mindcrime »

hammock wrote: post #71
throwway120385 wrote: post #50

Earlier quoted context omitted.

This is pretty much spot on. It sucks after 250 years of hindsight, but I would encourage anyone who wants to think like Franklin to buy an amber rod, a glass rod, a piece of real fur, and a piece of silk, and try experimenting with them and see if you can intuit from physical experiment what the fire is made of and how it passes from one material to another. You can't without the benefit of future knowledge. This is…

What is an amber rod?

Just what it sounds like: a rod made of amber[1].

[1]: https://en.wikipedia.org/wiki/Amber

Re: Why does current flow the opposite way from the electrons?

#103

Post by marmadukester39 »

bequanna wrote: post #78
AnotherGoodName wrote: post #74

Earlier quoted context omitted.

Thinking of it as directional action potentials that are blocked by mass? I agree it does feel intuitively nicer that way honestly.

Yep. Coming from everywhere and moving outward in all directions at all times and ‘absorbed’ or ‘blocked’ by mass

Physicists: Has anyone ever looked into this?

Re: Why does current flow the opposite way from the electrons?

#104

Post by ooopdddddd »

nitwit005 wrote: post #5

Could be worse. They could have chosen any term implying opposite. We could have had left and right handed charges. Although I suppose we essentially did that when naming the quarks.

Up and down quarks have names that make perfect sense, they are derived from the isospin which in turn derives from spin (spin-1/2 was the only other well-known object in physics that had the same symmetry properties). Which one is up and which one is down is the only arbitrary choice.

Using "positive" and "negative" would have been a disaster. What charge does a positive antiquark have?

Re: Why does current flow the opposite way from the electrons?

#105

Post by philipov »

throwway120385 wrote: post #13

Because he didn't know anything about electrons, and the experiment he did involving rubbing amber and glass rods on fur and silk cloth only showed that something was transferred between the two materials, and that when the material containing the substance was brought near to the other material containing the other substance, the property conferred by the substances appeared to negate. If you read Teaching Introduct…

> We could just as easily have called it "black" or "white" charge

And when we found a charge system that had 3 charges rather than just two, we did.

Re: Why does current flow the opposite way from the electrons?

#106

Post by lukeasrodgers »

Gibbon1 wrote: post #24
CapitalistCartr wrote: post #6

A big part of this is we measure what's important to us. As an electrician, what's important is which wire is full of angry pixies. They're technical direction of travel is far less important to my job (and my safety). When doing electronics, the direction of travel becomes quite important. So there's a different point of view.

Anytime electrochemistry is involved it's important. But regular electronics not very much. I think positive and negative mostly trips up people trying to use what they think is happening to explain theory. When it's not that useful most of the time. What I could never keep straight is anode and cathode.

It doesn't help that very many explanations on the web of anode/cathode are wrong, or at least misleading, and only cover catalytic or galvanic cells.

I believe https://chemistry.stackexchange.com/questions/16785/positive... is correct.

Re: Why does current flow the opposite way from the electrons?

#107

Post by sudhirj »

detourdog wrote: post #89
a1445c8b wrote: post #73

Earlier quoted context omitted.

Using the word “accumulator” wouldn’t be enough to differentiate batteries from capacitors, inductors, etc. which are also accumulators.

In system design that distinction may not matter.

Seems like capacitors, inductors and batteries differ only quantitively in their response curves, not in qualitatively? As in they all do different things to the circuit on the voltage, amperage and time axis? We would need separate words for them, but accumulators seems like a decent umbrella.

Re: Why does current flow the opposite way from the electrons?

#109

Post by abecedarius »

samatman wrote: post #54
Gibbon1 wrote: post #24

Earlier quoted context omitted.

Anytime electrochemistry is involved it's important. But regular electronics not very much. I think positive and negative mostly trips up people trying to use what they think is happening to explain theory. When it's not that useful most of the time. What I could never keep straight is anode and cathode.

It's easy! Cations are positively charged, so cathodes are, uh, negatively, charged. With anions and anodes it's the other way around. It makes perfect sense! Cations, you see, are attracted to anions. And reduced by cathodes. Anions? Attracted to cations. And oxidized by anodes. Whereas cations are oxidized by anions, and anions are reduced by cations. The only alternative here would be if cathodes and cations were…

The other day, I was reading a chemistry book at the point where it "helpfully" listed four different mnemonics for the same thing -- cations vs. anions, or maybe it was cathodes vs. anodes, or anyway, you know, something in that vicinity.

I just let my eyes skip over that list. I refuse to be the Jaguar in "Just-So Stories" https://etc.usf.edu/lit2go/79/just-so-stories/1294/the-begin...

Re: Why does current flow the opposite way from the electrons?

#110

Post by dotnet00 »

pdonis wrote: post #32
throwway120385 wrote: post #13

Because he didn't know anything about electrons, and the experiment he did involving rubbing amber and glass rods on fur and silk cloth only showed that something was transferred between the two materials, and that when the material containing the substance was brought near to the other material containing the other substance, the property conferred by the substances appeared to negate. If you read Teaching Introduct…

> there is no way of knowing the direction of the charge But there is--otherwise we wouldn't know that Franklin got it backwards. He thought the charge carriers were going one way, and chose the convention he did because he thought it matched the way the charge carriers were going, but it turns out they were going the other way. The signs of the charges are a convention--and the fact that we still use Franklin's conv…

I think they don't mean it in the literal "you physically can't tell the direction of charge at all" sense.

As you say, the very fact that we know the real direction counters that. They mean that within the abstract context of electronics presented in introductory physics, the real direction of charge doesn't matter and cannot be determined. As long as you pick one consistent convention and stick to it, the math will always work out the same, since depending on convention, all the directions and signs are equally flipped. The real direction of charge only matters when you get deep into the details (eg semiconductors).

At the level of detail of introductory physics, it's effectively a symmetry, similar to how given the simultaneous flipping of charge, parity and time, you cannot tell the difference.

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