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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?

#41

Post by Thrymr »

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.

A CRT display is a "cathode ray tube", which shoots electrons, which are negative.

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

#42

Post by zer00eyz »

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.

Rome was about 2500 years ago.

The first recorded name, 5000 years.

Oldest human structures 10k years.

Humans, about 130k years.

Our oldest "ancestors" 300-400k.

3.7 billion years.

For you, not so recent. In the grand scheme of things it was a heartbeat ago.

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

#44

Post by electrodank »

boring-alterego wrote: post #39

Fun fact when in 2 year school for electronics engineering technology we learned the current flow with the electrons, and in my 4 year electrical engineering school I learned it by following electron holes. You'll find basic electrical circuits books sometimes have an electron flow edition.

Any recommendations for the circuit books?

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

#45

Post by jonny_eh »

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…

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

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

#47

Post by hn_throwaway_99 »

jonny_eh wrote: post #45
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…

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, it kinda sucks because I think Franklin just "picked wrong".

I.e. it would make much more sense to me if the absence of electrons (i.e. holes) were negative by convention and an abundance of electrons were denoted as positive.

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

#48

Post by card_zero »

akira2501 wrote: post #28
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…

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.

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

#50

Post by throwway120385 »

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…

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 it feels like to stand on the shoulders of giants.

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