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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?

#71

Post by hammock »

throwway120385 wrote: post #50
hn_throwaway_99 wrote: post #47

Earlier quoted context omitted.

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…

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?

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

#72

Post by tonyarkles »

bilsbie wrote: post #68

I’ve always wondered if there are any applications where it matters which way the electrons are going. Anyone know?

Cathode Ray Tubes probably wouldn't work very well if they sucked electrons away from the screen instead of launching them towards it.

At a deeper level it does start to matter when you get down to the physical level of transistors because electrons and holes (places in a crystal lattice where an electron could go but isn't there) move differently. P-type transistors generally can't be made as conductive as N-type transistors because, with plenty of handwaving, negative charge due excess electrons move easier than positive charge due to a lack of electrons.

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

#73

Post by a1445c8b »

somat wrote: post #52
detourdog wrote: post #38

Earlier quoted context omitted.

I often prefer the original language of discovery. My favorite is the term accumulator compared to battery.

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.

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

#74

Post by AnotherGoodName »

bequanna wrote: post #70
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…

As a layperson, that makes sense to me. It also explains the time dilation effect when near a large mass.

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

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

#75

Post by a1445c8b »

card_zero wrote: post #48
akira2501 wrote: post #28

Earlier quoted context omitted.

It really seems like had a rationale: "We suppose as aforesaid, That Electrical Fire is a common Element, of which every one of the three Persons abovementioned has his equal Share before any Operation is begun with the Tube. A who stands on Wax, and rubs the Tube, collects the Electrical Fire from himself into the Glass; and his Communication with the common Stock being cut off by the Wax, his Body is not again imme…

Hmm. "We rub our Tubes with Buck Skin", he says in the same letter. I was trying to work out whether the tube gets a positive or negative charge. I think it depends on what material is being rubbed with what: https://en.wikipedia.org/wiki/File:Triboelectric-series_EN.s... The tube is glass, but is the buckskin fur, or slightly furry, or leathery? That would seem to alter the charge it gets.

> Hmm. "We rub our Tubes with Buck Skin", he says in the same letter.

My immature brain didn’t get past this sentence.

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

#76

Post by Yaa101 »

It does not, it just seems that way. The electron just jumps to an empty slot in the next atom (metals have empty electron slots in their atoms, that is why they conduct energy) and leaves a bit of energy in the current one. So if the electron jumps to the next atom on the right, the current seems to go left.

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

#77

Post by gus_massa »

bilsbie wrote: post #68

I’ve always wondered if there are any applications where it matters which way the electrons are going. Anyone know?

https://en.wikipedia.org/wiki/Hall_effect If you put a magnetic field that is perpendicular to the current, you get a charge in one dide of the wires that depends on the moving charges. This is used to measure magnetic fields.

https://en.wikipedia.org/wiki/Vacuum_tube usualy you heat only one electrode, but you must heat the correct one so electrons can jump to the other electrode.

https://en.wikipedia.org/wiki/Cathode-ray_tube I'm not sure if it'a a different example or just a variation. Anyway, you can have a lot of fun changing the pressure of the gas, and the electric field https://www.daviddarling.info/encyclopedia/D/discharge_tube....

https://en.wikipedia.org/wiki/Transistor IIRC they are also not symetric, but my knowdledge is too small even to write a good remark.

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

#78

Post by bequanna »

AnotherGoodName wrote: post #74
bequanna wrote: post #70

Earlier quoted context omitted.

As a layperson, that makes sense to me. It also explains the time dilation effect when near a large mass.

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

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

#79

Post by gus_massa »

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...

Those videos are misleading. Electrons flow inside the wires. They just flow much slower than what you would expect. When you close a circuit, the information that it was closed goes very fast but the electrons flow slowly.

(It happens also with water, if you have the shower with only very hot water and you open the cold one, the output of the shower changes almost instantly but you need like a second to get the mixed water with that is warm.)

What flows outside the wires is the energy. It's very unintuitive but it's true. Feynman has a nice lecture about it. But note that most of the energy flows very close arround the wires, a very small part wanders far away.

There is an exception when you have a radio transmissor with an antena and a reciver. Then the energy flows just through the air (or vacuum). Also when you have a light lamp or a laser.

Actualy every electric circuit emit some radiation as a bad radio tranmisor. But most of the times you can ignore it.

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

#80

Post by [deleted] »

ars wrote: post #26
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.

Actually both wires are full of angry pixies, it's just that you have angry pixies in your body that match the ones in one of the wires, so you don't notice when you touch one, and strongly notice when you touch the other. On top of that if we did not ground one side of the electrical network, you could touch either wire and feel nothing. That's called an isolated ground, and is not commonly used except in hospitals…

[deleted]
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