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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?

#121

Earlier quoted context omitted.

> 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 .

Where can I learn more on this? Searching yields nothing.

Quarks and gluons, or quantum chromodynamics

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

#122

Earlier quoted context omitted.

> 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 .

Where can I learn more on this? Searching yields nothing.

I imagine they're referring to https://en.m.wikipedia.org/wiki/Quantum_chromodynamics

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

#123
post #101

Earlier quoted context omitted.

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:

[deleted]

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

#124
post #96
post #26

Earlier quoted context omitted.

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…

I was under the impression that we primarily ground one side to prevent atmospheric charge and/or things like lightning strikes causing large voltage differentials to occur between power lines and grounded objects (it's probably a bit of a fire and safety risk if the wires coming into your house could be sitting many kV above earth potential).

Yes. If you have an electrical network that isn't grounded anywhere you can't get a shock from touching only one wire because there wouldn't be any current flow. If you repair electronics you might do that to a single device with an isolating transformer, or if you are a hospital you might do that to the entire building.

But at the scale of a national grid it's basically impossible to ensure that the entire grid is isolated from the ground all the time. Stuff breaks. And if the network is grounded in some far away place but not anywhere near you you get exactly the effect you describe: you have some unknown and potentially large voltage differential towards ground because the literal ground doesn't have the same potential everywhere. So instead you give up and tie one of the potentials to ground, and do that as often as viable.

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

#125

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…

The reason why which charge is named positive and which is named negative does not matter is because in all the equations that relate electric charge with other measurable physical quantities we never have an electric charge alone, but we always have the product of two electric charges.

The value of the product of two electric charges is invariant to the convention chosen for the sign of the electric charge.

Numbers and numeric quantities are actually a real thing that exists in the world. They do not exist only in our minds (and in the minds of many other animals who are also able to count until some small number). And so does the concept of negation, which clearly is a property of the world, independent of humans or animals.

For other physical quantities, the sign of a quantity is not arbitrary, like for the electric charge, because those are used in expressions that are not invariant to sign changes.

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

#126

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…

What you are describing is a meme in my country, used to make fun of religious anti-evolution people who claim "evolution is only a theory and not a proven law, thus doesn't exist".

We call gravity "yer çekimi", which literally means "the pull of ground". The meme is "Ya yer çekimi yoksa da gök itimi varsa?" which translates to "What if the gravity doesn't exist but sky-push does?".

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

#127

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…

Turn it into a theory that predicts exact quantities (accelerations) and I will start paying attention.

The idea he's describing is Le Sage's theory of gravity, and it does correctly predict many of the things Newtonian gravity predicts. Specifically it predicts an inverse square attraction between pairs of bodies and that the attraction is proportional to the masses of the bodies.

It turns out it doesn't quite work, but it is interesting enough try that does get enough things right that quite a few well known physicists over the years have taken a look at it. The Wikipedia article on it covers a lot of them [1].

Feynman talks about it briefly in section 7-7 of volume I of the Feynman lectures [2]:

> Many mechanisms for gravitation have been suggested. It is interesting to consider one of these, which many people have thought of from time to time. At first, one is quite excited and happy when he “discovers” it, but he soon finds that it is not correct. It was first discovered about 1750. Suppose there were many particles moving in space at a very high speed in all directions and being only slightly absorbed in going through matter. When they are absorbed, they give an impulse to the earth. However, since there are as many going one way as another, the impulses all balance. But when the sun is nearby, the particles coming toward the earth through the sun are partially absorbed, so fewer of them are coming from the sun than are coming from the other side. Therefore, the earth feels a net impulse toward the sun and it does not take one long to see that it is inversely as the square of the distance—because of the variation of the solid angle that the sun subtends as we vary the distance. What is wrong with that machinery? It involves some new consequences which are not true. This particular idea has the following trouble: the earth, in moving around the sun, would impinge on more particles which are coming from its forward side than from its hind side (when you run in the rain, the rain in your face is stronger than that on the back of your head!). Therefore there would be more impulse given the earth from the front, and the earth would feel a resistance to motion and would be slowing up in its orbit. One can calculate how long it would take for the earth to stop as a result of this resistance, and it would not take long enough for the earth to still be in its orbit, so this mechanism does not work. No machinery has ever been invented that “explains” gravity without also predicting some other phenomenon that does not exist.

[1] https://en.wikipedia.org/wiki/Le_Sage%27s_theory_of_gravitat...

[2] https://www.feynmanlectures.caltech.edu/I_07.html

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

#128

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…

>We say B (and other Bodies alike circumstanced) are electrised positively; A negatively: Or rather B is electrised plus and A minus. And we daily in our Experiments electrise Bodies plus or minus as we think proper. These Terms we may use till your Philosophers give us better.

Sounds like he leaves it open for future "Philosophers" to update the convention as our understanding of the phenomena that he had documented improved. Smart guy in not assuming that he got it right the first time. Franklin sounds like he wasn't a "my way or the highway" type of guy.

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

#129
post #36

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…

It’s really strange reading the words of such an intelligent person beginning to understand something back then that is so fundamental today that even laypeople understand it more scientifically. Really weird, but really cool to get a peek back into a scientific mind in the 1700s.

Indeed! I love reading Benjamin Franklin for exaclty that. If you haven't read it, Walter Isaacson's biography on Franklin is absolutely fascinating. Brilliant, hilarious, driven, and wildly accomplished. The dude was (IMHO) one of the most interesting humans to have ever lived. Highly recommend.

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

#130

Earlier quoted context omitted.

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

> inductors, etc. which are also accumulators. In what sense do inductors accumulate? Batteries and capacitors accumulate (i.e. integrate) current. Inductors differentiate current: v = L di/dt means you get voltage out of current changes.

Inductors accumulate a magnetic field.
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