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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?

#81

Post by gavmor »

lazide wrote: post #64
throw0101d wrote: post #59

Earlier quoted context omitted.

> Numbers and numeric quantities aren't a real thing that exists in the world. They exist only in our minds. Is math invented or discovered? * https://www.sfu.ca/~rpyke/cafe/livio.pdf See also "The Unreasonable Effectiveness of Mathematics in the Natural Sciences" by Wigner: * https://en.wikipedia.org/wiki/The_Unreasonable_Effectiveness...

Was ‘Blue’ invented or discovered? Fundamentally, it’s the same type of problem - and really more of a philosophical thing.

We're using the term "Blue" ambiguously.

The term was invented; its assignment and scope were invented, too. The wavelengths themselves were discovered.

So there are two different "Blues;" signifier and signified.

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

#82

Post by gavmor »

lazide wrote: post #64
throw0101d wrote: post #59

Earlier quoted context omitted.

> Numbers and numeric quantities aren't a real thing that exists in the world. They exist only in our minds. Is math invented or discovered? * https://www.sfu.ca/~rpyke/cafe/livio.pdf See also "The Unreasonable Effectiveness of Mathematics in the Natural Sciences" by Wigner: * https://en.wikipedia.org/wiki/The_Unreasonable_Effectiveness...

Was ‘Blue’ invented or discovered? Fundamentally, it’s the same type of problem - and really more of a philosophical thing.

We're using the term "Blue" ambiguously.

The term was invented; its assignment and scope were invented, too. The wavelengths themselves were discovered.

So there are two different "blues;" sigmifier, and signified.

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

#83

Post by kevin_thibedeau »

xdavidliu wrote: post #27
NegativeLatency wrote: post #3

It was only relatively recently we figured started to understand some sort of model of what the inside of the atom is: https://en.wikipedia.org/wiki/Plum_pudding_model

how is this recent? This was like 1900.

The Nobel prize for proving the existence of molecules was awarded in 1926. Less than 100 years ago. Our understanding of physical chemistry is extremely recent.

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

#84

Post by crote »

lazide wrote: post #64
throw0101d wrote: post #59

Earlier quoted context omitted.

> Numbers and numeric quantities aren't a real thing that exists in the world. They exist only in our minds. Is math invented or discovered? * https://www.sfu.ca/~rpyke/cafe/livio.pdf See also "The Unreasonable Effectiveness of Mathematics in the Natural Sciences" by Wigner: * https://en.wikipedia.org/wiki/The_Unreasonable_Effectiveness...

Was ‘Blue’ invented or discovered? Fundamentally, it’s the same type of problem - and really more of a philosophical thing.

The interesting part is that perception is shaped by language. The Ancient Greeks did not have a word for blue, which led to things like the sky being described as "wine-colored" or "bronze". Similarly, the English "blue" is split into two in Russian: light blue (голубой – goluboy) and deep/dark blue (синий – siniy), a speaker has to choose between them when describing something.

The wavelengths may have always existed but colors only become a thing when we draw the arbitrary lines between them.

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

#86

Post by mensetmanusman »

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…

“Numbers and numeric quantities aren't a real thing that exists in the world.”

How did your mind gain access to this universal truth? ;)

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

#87

Post by mensetmanusman »

hn_throwaway_99 wrote: post #47
jonny_eh wrote: post #45

Earlier quoted context omitted.

In a way he was right, if he was describing the movement of "holes", or the lack of an electron.

This is exactly why I think he was wrong . Normally, pretty much everywhere else we use the terms, "positive" denotes the presence or addition of something, while "negative" denotes the absence or subtraction. So while I agree with the GP's comment that Franklin didn't know anything about electrons, so he arbitrarily picked one as negative and the other as positive, now that we do know about the movement of electrons…

Not really, we talk about bubbles moving up, not water moving down.

Current is bubbles.

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

#88

Post by sobellian »

beryilma wrote: post #65

I dont understand all the details, but Veritasium and others on YouTube have videos on how the current/electron flow is also an illusion. Since electricity and magnetism are really fields per Maxwell equations, the current flow and other electrical things that we attribute to the inside of the wire are really happening outside of the wires as electric fields. They have a much better explanation than mine certainly...

Current really isn't flowing through the air. The relevant equation for resistive materials is J = sigma E; J is current density, E is the electric field, and sigma is resistivity. Air's resistivity is huge - if you pump any significant current through air you will cause arcing.

What really happens when you transmit energy through air is charge accumulation. Think of a parallel-plate capacitor - electrons accumulate on one side of the plate and holes on the other side. If you draw a black box around the system, it looks like current is flowing through it. But no significant current is actually going through the dielectric, or you will ruin the capacitor.

Electrical engineers model the phenomenon that Veritasium pointed out as capacitive coupling. In a circuit diagram, we would literally just draw an additional capacitor in between the relevant circuit elements.

In DC, this doesn't really matter after a certain settling time because the capacitor has settled to a certain charge. But in AC (or DC right after you flip the switch) it is non-negligible.

Edited to add - to be clear, there IS an electric field in the air - but the current density is negligible unless you've caused dielectric breakdown.

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

#89

Post by detourdog »

a1445c8b wrote: post #73
somat wrote: post #52

Earlier quoted context omitted.

That is a much better term, battery: inconsequential detail on how it is constructed. accumulator: what it does.

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.

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

#90

Post by ViktorRay »

AnotherGoodName wrote: post #66

It wouldn’t surprise me if at some point in the future we realise mass shields us from a gravitational field that pushes everything in all directions at once as opposed to our current thinking that mass emits a field that pulls us towards it. Eg. imagine the earth below you shielding you from a force that otherwise pushes all mass in all directions constantly. You’re now more shielded from the push in the direction o…

Well I guess that explains why "the normal force" is the one that counteracts gravity.

(for those of you who don't know, the super simplified explanation in physics 101 is that the normal force is the vector that pushes up while gravity pushes down for objects that are resting on top of each other)

So I guess the one who named it "the normal force" would be more correct that he ever imagined if your theory of gravity was the real correct one!

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