Electroboom: How Right IS Veritasium?! Don't Electrons Push Each Other??

[Sredni]

It’s all a protracted ego flex for YouTubers to show how intelligent they are (The real reason is actually just earning convenient ad revenue for a string of pointless videos)

The successive back-and-forth videos replying to one another are surely both an ego thing, and most of all, a way for them to protect their image (which you must realize is for them a business), and I can understand that. In other words, that ends up getting annoying, but they unfortunately don't have much choice. If they leave someone else "debunk" their videos without replying to that, they are by default acknowledging they were wrong, and thus their image gets a dent and their YT channel loses credibility.

Yeah, and when they are wrong they need to spin it, like Science Asylum did with his animation on energy transfer, or Electroboom itself, falsely stating that Feynman and Belcher agreed with him on applying KVL on an unlumpable circuit (no, both were talking about lumped circuits). Minor youtubers simply resort to censor critic comments (like fromjesse and RSD Academy) and sometimes they redo their videos multiple times and hide the ones where their ignorance was exposed (RSD Academy).

Doesn't mean that what's being discussed is not interesting. But you must realize that this is a general problem with online discussions, especially when someone cares about their image. You just can't let others "debunk" you if you think you're right or that the other has not fully understood your point. Letting them is akin to approving. Of course, unless you were actually wrong, which can happen, in which case the appropriate reply is just to admit you were. But in many cases, as with this discussion, there is no fundamental "wrong" in any of what Veritasium, Electroboom and others have said. Those are just different points of view, and they are essentially debating models, none of which is fully accurate or fully depainting "reality". Our models are just useful tools. Just my 2 cents.

Well, yes and no. Yes, models are imperfect and the map is not the territory. But no, sometimes there is a right side and a wrong side.
In this last video Mehdi exposes the root of his misunderstanding: it really looks like he was unaware of the role of surface charge in simple electric circuits. And he has a problem with superposition, too. When he tries to picture the electric field that the rings of charge create inside the conductors he only considers the field of the charges inside and on the surface. But what about the original field, that generated by the battery?
Thinking that the field experienced by electrons inside the conductor is only the field generated by said charges is what prevented him to understand why voltage is path depedendent. In the case of Lewin's ring he was not accounting for the external Eind field. Now he is not accounting for the external Ebatt field (let's call it this way).
The charge on the surface of the conductor is disposed that way because it is reacting to the external field imposed by the battery. It's the superposition of the original external field and the surface charge field that gives rise to the Etot = j / sigma field that obeys Ohm's law in the conductor.

So, no. "It's raining" and "Tt's sunny" are not two different points of view. One is right, the other one isn't.

By the look of it, Derek is just 4-5 remote calls away from dubbing Mehdi a flatearther.

[electrodacus]

Yeah, and when they are wrong they need to spin it, like Science Asylum did with his animation on energy transfer, or Electroboom itself, falsely stating that Feynman and Belcher agreed with him on applying KVL on an unlumpable circuit (no, both were talking about lumped circuits). Minor youtubers simply resort to censor critic comments (like fromjesse and RSD Academy) and sometimes they redo their videos multiple times and hide the ones where their ignorance was exposed (RSD Academy).

I'm not that familiar with those youtube channels but removing videos that contain a wrong explanation is probably the best way to go about it.
What will you prefer ?

Well, yes and no. Yes, models are imperfect and the map is not the territory. But no, sometimes there is a right side and a wrong side.
In this last video Mehdi exposes the root of his misunderstanding: it really looks like he was unaware of the role of surface charge in simple electric circuits. And he has a problem with superposition, too. When he tries to picture the electric field that the rings of charge create inside the conductors he only considers the field of the charges inside and on the surface. But what about the original field, that generated by the battery?
Thinking that the field experienced by electrons inside the conductor is only the field generated by said charges is what prevented him to understand why voltage is path depedendent. In the case of Lewin's ring he was not accounting for the external Eind field. Now he is not accounting for the external Ebatt field (let's call it this way).
The charge on the surface of the conductor is disposed that way because it is reacting to the external field imposed by the battery. It's the superposition of the original external field and the surface charge field that gives rise to the Etot = j / sigma field that obeys Ohm's law in the conductor.

So, no. "It's raining" and "Tt's sunny" are not two different points of view. One is right, the other one isn't.

By the look of it, Derek is just 4-5 remote calls away from dubbing Mehdi a flatearther.

Derek is completely wrong and Mehdi has enough gap in understanding that it was easily confused by Derek.
Derek knows that he has gaps in understanding this but he published two videos on the subject.

Electric current is defined as a stream of charged particles traveling through a conductor or space (as in the vacuum diode I mentioned in last post).
There are no stream of charged particles in Dereks example outside of the wire.  Since current is only through wire energy only travels in wire in his example.
Lewin has no idea of what he was doing in that experiment as Mehdi correctly pointed out.
The lumped circuit model for a transmission line provides the correct result and it is a simplification/reduction in order to be able to do the calculation.
The one that could be considered a flat earther will be Derek at least based on this two videos about how electricity works and the ones about direct downwind faster than wind vehicle where he is basically saying he has a overunity device.
In both cases is about understanding what energy and energy storage is.

[pcprogrammer]

Minor youtubers simply resort to censor critic comments (like fromjesse and RSD Academy) and sometimes they redo their videos multiple times and hide the ones where their ignorance was exposed (RSD Academy).

Funny you say this and it sure is happening. There was this video about a problem with the FNIRSI-1013D touch panel and the youtuber fixed it basically without knowing what he was doing. So I left a comment about that he was wrong and that there is a thread on EEVblog where this scope is discussed and reverse engineered. The comment did not became public and when I viewed the video a while later the schematic I made was shown to point out how the touch panel was connected. It was still advocating the original solution of a resistor to ground.

For some reason I seem to be unable to post comments on youtube on other channels than my own. For instance I commented the FNIRSI-1014D review and tear down video Kerry Wong made, pointing out that he should have done his homework and looked on EEVblog before making his video, but that was also not published

[Sredni]

Yeah, and when they are wrong they need to spin it, like Science Asylum did with his animation on energy transfer, or Electroboom itself, falsely stating that Feynman and Belcher agreed with him on applying KVL on an unlumpable circuit (no, both were talking about lumped circuits). Minor youtubers simply resort to censor critic comments (like fromjesse and RSD Academy) and sometimes they redo their videos multiple times and hide the ones where their ignorance was exposed (RSD Academy).

I'm not that familiar with those youtube channels but removing videos that contain a wrong explanation is probably the best way to go about it.
What will you prefer ?

Absolutely. Removing the wrong explanation and replacing it with the correct explanation is the way to go.
Removing the wrong explanation and replacing it with the same wrong explanation -while removing some of the errors, not so much. Especially when it's done to reset the comments after banning users who pointed out the remaining errors in previous videos.

Derek is completely wrong
...
Lewin has no idea of what he was doing in that experiment...

Have you ever consider the possibility that it might be you going the wrong way on the highway?

[Sredni]

Minor youtubers simply resort to censor critic comments (like fromjesse and RSD Academy) and sometimes they redo their videos multiple times and hide the ones where their ignorance was exposed (RSD Academy).

Funny you say this and it sure is happening. There was this video about a problem with the FNIRSI-1013D touch panel and the youtuber fixed it basically without knowing what he was doing. So I left a comment about that he was wrong and that there is a thread on EEVblog where this scope is discussed and reverse engineered. The comment did not became public

Youtube is very strong in gaslighting.
It does not allow external links that are not links to youtube (or shortcuts to youtube videos - there might be some other minor exception). I no longer post comments with links because they will be automatically deleted  - sometimes I can still see them from my account when I am logged in, most of the times they dissapear from my history as well.
Even worse, I have noticed that youtube deletes also comments where one explains how to reach a certain internet page without giving a link. I believe there is some form of AI that is dedicated to that.
I have also noticed that when there is an ongoing discussion, some words might trigger youtube's censorship. Your comment will be deleted, but you will still be able to see it as if it was published. This is the real gaslighting. It is possible they are doing this to prevent flame wars and degeneration (you think you had the last word and your opponent had nothing to reply - and the same goes for your opponent).

It is scary how this imposed censorship can be used to drive public opinion, by carefully tweaking the algorithms... This is Orwell level stuff.

(Very often the channel owner has nothing to do with it)

[pcprogrammer]

I just gave up. I tried without links and that did not work either, but maybe it triggers on EEVblog or github and still removes comments that mention those.

It is a bit of a shame how this kills the original idea of a fully open platform, but the truth is that people can't handle a fully open platform. As you say it will go up in proverbial flames with a lot of mud slinging and thus leading to nowhere.

[HuronKing]

By the look of it, Derek is just 4-5 remote calls away from dubbing Mehdi a flatearther.

It was interesting to me that Mehdi retreated into the "electrons are pushing AND pulling" explanation like two ends of a chain and sprocket or two ends of a water pump... Derek says "that's nice... that's nice"... WHEN THIS IS THE EXACT ANALOGY DEREK WAS DEBUNKING IN HIS FIRST VIDEO! 

He slips it in "and if we add the idea of field interaction then we're totally in agreement" and Mehdi's all "yea yea, whatever, I'm right too!"

Lol.

[electrodacus]

Have you ever consider the possibility that it might be you going the wrong way on the highway?

I see no evidence for that.  As soon as I can see the evidence I will apologize and turn around going the correct way.

There is no evidence showing that energy travels through a capacitor (basically what Derek is saying) and all evidence points that energy flows in to a capacitor when charging and out of the capacitor when discharging.

Same for direct downwind faster than wind vehicle where energy is being stored when vehicle is below wind speed then that stored energy is what allows the vehicle to exceed wind speed but only for a limited amount of time proportional with the amount of energy stored.

[electrodacus]

It was interesting to me that Mehdi retreated into the "electrons are pushing AND pulling" explanation like two ends of a chain and sprocket or two ends of a water pump... Derek says "that's nice... that's nice"... WHEN THIS IS THE EXACT ANALOGY DEREK WAS DEBUNKING IN HIS FIRST VIDEO! 

He slips it in "and if we add the idea of field interaction then we're totally in agreement" and Mehdi's all "yea yea, whatever, I'm right too!"

Lol.

While all analogies have limitations the one with "electrons are pushing AND pulling" is way closer to what happens in reality.
What Mehdi was trying to say by "I'm right too" is that his analogy works in all applications and never gives an incorrect result but since he was confused by Derek's explanation and did not had a counter argument he also accepted Derek's incorrect analogy considering that may be a valid alternative analogy when it is not.
That is about what happened with the professor that lost 10K due to his inability to explain how the small toy vehicle can drive on the treadmill against the direction the treadmill was moving. For him that should be impossible as he completely ignored the fact that propeller stores energy by creating a pressure differential while vehicle was kept in place with the hand and then when released that stored energy is what pushed the vehicle in the opposite direction that treadmill surface was moving.
So vehicle was no longer powered by treadmill (that will be impossible) but powered by stored energy. The treadmill was way to short to show that vehicle stops accelerating and moves backward after stored energy is used but if video was taken from the side you can see the rate of acceleration dropping as the stored energy is being used up. Likely people either forgot that air is a compressible fluid or do not know what that is and is not helpful that air is invisible.
If most people have problems understanding air as a compressible fluid I do not expect to understand even more abstract things like electrons.

[Naej]

By the look of it, Derek is just 4-5 remote calls away from dubbing Mehdi a flatearther.

It was interesting to me that Mehdi retreated into the "electrons are pushing AND pulling" explanation like two ends of a chain and sprocket or two ends of a water pump... Derek says "that's nice... that's nice"... WHEN THIS IS THE EXACT ANALOGY DEREK WAS DEBUNKING IN HIS FIRST VIDEO! 

He slips it in "and if we add the idea of field interaction then we're totally in agreement" and Mehdi's all "yea yea, whatever, I'm right too!"

Lol.

Maybe Derek finally realized he didn't debunk anything?

[EPAIII]

OK good old OHM's law tells us that the current is inversely proportional to the resistance.

I = E / R

So, with two wires of equal length and all other things also equal (like the path followed or whatever other factors), but with different resistances will carry different currents. Now, how do those currents differ?

The resistance in a conductor is directly proportional to it's length and INVERSELY proportional to it's cross sectional area. Look about 1/4 of the way down the page:

https://en.wikipedia.org/wiki/Electrical_resistance_and_conductance

R = p (l / A)

p is a constant
l is the length of the conductor
A is the cross sectional area of the conductor

A, the cross sectional area is the full area, not just some fraction of it that is near the surface. It does not matter what shape that cross section may be. A round conductor, a square conductor, and a thin but very wide rectangular conductor (like sheet metal or even metal foil), each with the same cross sectional area and the same constant (p) will have the same resistance per unit length and will have the same resistance. So they will all carry the same current - all else being equal, of course. And combining this with Ohm's law, we see that the current is directly proportional to the cross sectional area (A).

A solid, round conductor, like ordinary solid wire, will have far fewer surface charges than a conductor made of thin foil but with the same cross sectional area. But they will carry the same current - all else being equal. If conduction relied on just the surface charges being distributed in a manner from one end of the conductor to the other that produced an E field gradient, then there would be a lot more surface charges on the surface of the foil conductor than on the solid, round one. And those charges would be a lot closer to the electrons inside the conductor so they would exert a lot more force on the interior electrons which would then move faster. And faster moving charges would mean that more charge would pass a given point in a given amount of time - all else being equal again. So the current in the foil conductor would be greater.

BUT, this is NOT the case. The foil conductor has exactly the same current as the round wire conductor. Or as a square one. Or as a triangular one. Or as a star shaped one. Or as one of any other shape. The current is not changed by changes in the amount of surface area the conductor may have, but by the CROSS SECTIONAL AREA.

This seems to argue rather heavily against the idea that it is only the surface gradient that is causing the interior charges (electrons) to move down the conductor.

A further argument and perhaps a better one would be that it will take a finite amount of time, at least 1/c if I am not mistaken, for the initial field to propagate down the wire. So, regardless of weather the force on an internal charge (an electron) is created by only the surface charges or by both surface and interior charges, both the interior and exterior charges (electrons) near the negative battery terminal will start moving BEFORE the ones that are around the half way point in the circuit formed by the wire. Those charges near the negative battery terminal will therefore BUNCH UP. They will become more dense, both on the surface and in the interior. This will create a net negative region both on the surface and in the interior of the conductor. And this net negative region, this net negative charge will exert a force on the charges in front of it.

In the vernacular, it will PUSH those ELECTRONS ahead.

The exact opposite of this also occurs at the same time on the end of the conductor that is connected to the positive battery terminal except in that case a region of net positive charge is created and it will ATTRACT the negatively charged electrons on and IN the wire there. That attraction will then act on the regions of the wire, both surface and interior, in attracting the negative charges ever further down the wire from that positive battery terminal.

Again, in the vernacular, it will PULL those ELECTRONS toward the positive terminal.

In a time (<= l/c), those two effects will meet at the light bulb in the center of the wire loop and it will then have it's maximum current flowing in it so it will light up at full brilliance.

This is not to say that the light bulb may not also have some current flowing in it before that time. But the amount of that current will depend heavily on the exact physical arrangement of the wires between it and the battery terminals and switch.

In this I am assuming that the switch and battery are connected by a length of wire that is negligible.

[Sredni]

A solid, round conductor, like ordinary solid wire, will have far fewer surface charges than a conductor made of thin foil but with the same cross sectional area. But they will carry the same current - all else being equal. If conduction relied on just the surface charges being distributed in a manner

I have to stop you here.
You seem to think that the surface charge is the number of free electrons per atoms times the number of atoms that make up the surface of the conductor.
No, it's just a tiny, tiny, tiny, veeeeeeeeeery tiny amount of excess or missing charge that is forced to be there in order to have the whole conductor comply with Ohm's law in local form.

So, no, you can't say a priori what that charge would be by the shape of the cross section of the conductor. It depends on the field estabilished in the whole space by the battery, and the way the conductor is placed in the space around it (and also on the shape of the conductor, that fact that it might become twisted on itself, have sharp bends, kinks...).

The amount of surface charge for 'ordinary circuits' with 'ordinary currents' is so tiny that it sometimes can be equivalent to a handful of electrons. (I also wonder when the classical model will break down with small currents - one can hardly have fractions of electron charge...)

[electrodacus]

A solid, round conductor, like ordinary solid wire, will have far fewer surface charges than a conductor made of thin foil but with the same cross sectional area. But they will carry the same current - all else being equal. If conduction relied on just the surface charges being distributed in a manner

I have to stop you here.
You seem to think that the surface charge is the number of free electrons per atoms times the number of atoms that make up the surface of the conductor.
No, it's just a tiny, tiny, tiny, veeeeeeeeeery tiny amount of excess or missing charge that is forced to be there in order to have the whole conductor comply with Ohm's law in local form.

So, no, you can't say a priori what that charge would be by the shape of the cross section of the conductor. It depends on the field estabilished in the whole space by the battery, and the way the conductor is placed in the space around it (and also on the shape of the conductor, that fact that it might become twisted on itself, have sharp bends, kinks...).

The amount of surface charge for 'ordinary circuits' with 'ordinary currents' is so tiny that it sometimes can be equivalent to a handful of electrons. (I also wonder when the classical model will break down with small currents - one can hardly have fractions of electron charge...)

EPAIII is correct and I mentioned this in one of the other threads.
With DC current the charges will be distributed basically equal on the entire cross section of the wire.
With AC a lot more of the charges will be on the side of the conductor facing the return conductor so not equally distributed since the conductor forms a capacitor with the return wire.  With high frequency most of the charges will be close to the surface (still inside the conductor) so resistance of the same conductor will increase as you do not take advantage of the entire conductor.

This image is probably what is shown in schools and it is correct except for the fact that it is valid for a coaxial cable so the return path of that current is through the cylindrical shield around the wire drawn in the photo. If return wire is like in Derek's example on the side then density of charged particles will be higher on the side facing the return conductor with which it forms a capacitor.
This asymmetric charge distribution is only for the first few nanoseconds during transient in Derek's experiment and at steady state DC charges will basically be uniformly distributed. 

[Sredni]

...
You seem to think that the surface charge is the number of free electrons per atoms times the number of atoms that make up the surface of the conductor.
No, it's just a tiny, tiny, tiny, veeeeeeeeeery tiny amount of excess or missing charge that is forced to be there in order to have the whole conductor comply with Ohm's law in local form.

...

The amount of surface charge for 'ordinary circuits' with 'ordinary currents' is so tiny that it sometimes can be equivalent to a handful of electrons. (I also wonder when the classical model will break down with small currents - one can hardly have fractions of electron charge...)

EPAIII is correct and I mentioned this in one of the other threads.
With DC current the charges will be distributed basically equal on the entire cross section of the wire.
With AC a lot more of the charges will be on the side of the conductor facing the return conductor so not equally distributed since the conductor forms a capacitor with the return wire.  With high frequency most of the charges will be close to the surface (still inside the conductor) so resistance of the same conductor will increase as you do not take advantage of the entire conductor.

I was not talking about the electrons that make up the current.
I was talking about the surface charge: the excess electrons or lack thereof that - along with the original external field generated by the battery - shape the electric field inside the conductor in such a way that it be directed along the conductor axis and will have a magnitude that satisfies Ohm's law in its local form.

Read Chabay and Sherwood. Or Jackson's paper "Surface charges on circuit wires and resistors play three different roles" (American Journal of Physics 64 (7), July 1996), or one of the other references I have put in this answer: https://electronics.stackexchange.com/questions/532541/is-the-electric-field-in-a-wire-constant

[rfeecs]

I was not talking about the electrons that make up the current.
I was talking about the surface charge: the excess electrons or lack thereof that - along with the original external field generated by the battery - shape the electric field inside the conductor in such a way that it be directed along the conductor axis and will have a magnitude that satisfies Ohm's law in its local form.

Read Chabay and Sherwood. Or Jackson's paper "Surface charges on circuit wires and resistors play three different roles" (American Journal of Physics 64 (7), July 1996), or one of the other references I have put in this answer: https://electronics.stackexchange.com/questions/532541/is-the-electric-field-in-a-wire-constant

That's the steady state condition.  But how did the surface charges get there?  Maybe they "pushed" each other?

And what would happen if the electrons in the wire at some random instantaneous time ended up bunched up a little bit at one spot?  Maybe they would "push" each other apart?  (Of course the positive lattice atoms have a role, too, in "pulling" the electrons.)  Is the continuity equation and conservation of charge maintained by "pushing" and "pulling"?

It seems like the whole arrangement of surface charges and constant current at every point along the wire is created and maintained by charges "pushing" and "pulling" each other.

[Sredni]

They get there in the same way charge on a metallic body redistribute itself when immersed in an electric field: by reacting to the electric field. At first it's only the 'external' electric field, then when they move because of that, the new configuration of charges creates its own electric field and this will lead to a new resultant electric field and a new configuration, and so on. All done with relaxation times, so very fast and on timescales that will make the (classical) flow of charge due to the current as if it were a still photograph. The process of redistribution goes on until the constitutive relation in the material is satisfied. In electrostatics we end up with zero electric field inside the metallic body; in DC we end up with a constant electric field directed along the conductor.

If you move the wire, the distribution of electric charge on its surface will instantly change to produce the right value for E, but the current inside will not change (because the right value of E has not changed). The conduction electron (again in the classical sense of sea of charge that flows due to the electric field inside) are so slow, in comparison to the surface charge redistribution, that they won't even know you have moved the wire and surface charge has changed place.

But, yes, I suppose we can assume that presence of surface charge will be the result of a dynamical equilibrium: it's not the the electrons are fixed - they will move as the other conduction electrons, but they will *immediately* be replaced by other electrons. Locally, the excess and deficit of charge is what is responsible for pushing and pulling conduction electrons - but that charge is there due to the fields. If I have a resistor halfway to the moon, once the fields have put the surface charge in place at its extremes, it's that charge that will make the electrons inside the resistor accelerate - there, halfway to the moon - and then lose energy to the lattice and heat the resistor's body.

[electrodacus]

I was not talking about the electrons that make up the current.
I was talking about the surface charge: the excess electrons or lack thereof that - along with the original external field generated by the battery - shape the electric field inside the conductor in such a way that it be directed along the conductor axis and will have a magnitude that satisfies Ohm's law in its local form.

Read Chabay and Sherwood. Or Jackson's paper "Surface charges on circuit wires and resistors play three different roles" (American Journal of Physics 64 (7), July 1996), or one of the other references I have put in this answer: https://electronics.stackexchange.com/questions/532541/is-the-electric-field-in-a-wire-constant

What you call surface charge are electrons and if they move then you have a current.

The switch in Derek's experiment is a capacitor so when open you have an electric field between the two contacts separated by air.
While you have an electric field there is no energy transfer through that small air gap.
The contacts will need to be within a few micrometers from each other for an electron to be able to jump the gap at 20V (DC voltage source used in the experiment).
There is clearly no electron traveling through that 1 meter gap thus no energy travels from battery (source) to lamp (load).

Since there is an imbalance of electrons between the two contacts of the switch there is an electric field so a small force created by that.
Say distance between the switch contacts is 1mm (more than large enough so that electrons can not "fly" from one side to the other) and you move them to 2mm. When you do that you will put some mechanical energy in to the system to move the two contacts from 1mm to 2mm and that energy will end up as heat on the wires and lamp.
Since in Derk's experiment the wire resistance (those copper pipes) is orders of magnitude smaller than that 1kOhm resistor acting as the lamp most of that mechanical energy you put in to moving the contacts will end up as energy in the lamp very small amount lost as heat in the wies and some charging the battery (assuming battery is rechargeable or it is a capacitor).

So you move the contacts changing the capacity and provide energy to the lamp. But is not the battery that provides that energy but the mechanical energy is converted in to electricity  and all that energy is transferred through the wires.

[Sredni]

I was not talking about the electrons that make up the current.
I was talking about the surface charge: the excess electrons or lack thereof that - along with the original external field generated by the battery - shape the electric field inside the conductor in such a way that it be directed along the conductor axis and will have a magnitude that satisfies Ohm's law in its local form.

Read Chabay and Sherwood. Or Jackson's paper "Surface charges on circuit wires and resistors play three different roles" (American Journal of Physics 64 (7), July 1996), or one of the other references I have put in this answer: https://electronics.stackexchange.com/questions/532541/is-the-electric-field-in-a-wire-constant

What you call surface charge are electrons and if they move then you have a current.

It's a handful of electrons. Their contribute to the overall current is completely negligible.

But, go ahead, try expose your theory to John David Jackson:



I wouldn't dare.
I  am sleeping with the light on, tonight.

[electrodacus]

It's a handful of electrons. Their contribute to the overall current is completely negligible.

But, go ahead, try expose your theory to John David Jackson:

I wouldn't dare.
I  am sleeping with the light on, tonight.

Have you read my replay or just stopped at the first line.
It is not my theory. It is what everyone that understands what electrical energy is uses.

Search the definition for electrical current on google and first page Wikipedia will be good.
"An electric current is a stream of charged particles, such as electrons or ions, moving through an electrical conductor or space. "
Since you are not going to ionize air at 20V used in Derek's experiment we are talking about electrons.
No moving electrons no electrical current and no electrical current no electrical power and no electrical power means no electrical energy.
Unless you want to prove that electrons travel through 1m of air all electrical energy delivered from battery to lamp travels through wires.
Or you may disagree with the definition of electrical current but then it is on you to prove the one everyone else is using is wrong.

[rfeecs]

I was talking about the surface charge: the excess electrons or lack thereof that - along with the original external field generated by the battery - shape the electric field inside the conductor in such a way that it be directed along the conductor axis and will have a magnitude that satisfies Ohm's law in its local form.

So what happens with a superconducting wire?  Presumably the surface charges make the field inside the wire zero.  So what makes the current go?

[Sredni]

I was talking about the surface charge: the excess electrons or lack thereof that - along with the original external field generated by the battery - shape the electric field inside the conductor in such a way that it be directed along the conductor axis and will have a magnitude that satisfies Ohm's law in its local form.

So what happens with a superconducting wire?  Presumably the surface charges make the field inside the wire zero.  So what makes the current go?

Ah. Superconductors are quantum beasts. (Well, technically even ordinary conduction requires quantum theory to give quantitative agreement).
If we stay in the realm of classical ED, we can consider a perfect conductor as the limit of a resistive conductor for sigma->infinity. You need an infinitesimally small field to make the electrons move. But it can get tricky. Last year (?) Lewin posted a problem with a superconducting ring in a changing magnetic field. Basically what we call Lewin's ring but without resistors. What will happen? Only two people, among all those who were exposed to the problem (and they included several physics professors to which Lewin had emailed the problem) gave the correct solution. One is a professor in a University in Switzerland (IIRC) and the other is George Hniatuk (he has a youtube channel).

The solution is: no current inside the superconducting ring.

I had it wrong: my initial assumption was that the current would rise so rapidly - being a superconductor - that the small self inductance of the ring would act as a current limiter.  Then I saw George Hniatuk's comment (Nope. No current inside) - and knowing how he knows EM - I realized he was right. (Math and Physics are different - in math you can create the induced electric field magically inside the superconductor, in physics you must justify its presence there. How do you place it in? Surface charge will redistribute in such a way as to prevent it from entering the ring).

But this is not the reason I am telling you this. In the video (I will add a link tomorrow, now I need to sleep), or in the comments, Lewin made a very interesting statement. That to initiate a current in a superconducting ring you need... a resistor. You start your magnetic mumbo jumbo with the resistor inserted - and it's the field in the resistor that makes the electron go - once in the superconducting material they continue 'by inertia', and only after the current is established, you switch to a full superconducting ring.

Pretty crazy, uh?

[SiliconWizard]

OK good old OHM's law tells us that the current is inversely proportional to the resistance.

Did you know that Ohm was considered a lunatic (to put it mildly) by his peers back in the days? He got rehabilitated only after a relatively long time.

I wonder how it would have unfolded these days.

[tszaboo]

At this point Veritasium just needs to admit that he has no ide what he is talking about and he was using a textbook with flawed physics in it.
All this discussion about current density in a conductor is totally solved formulas, which tell us if there is current inside the conductor or not:
Here is one:

[Naej]

I was talking about the surface charge: the excess electrons or lack thereof that - along with the original external field generated by the battery - shape the electric field inside the conductor in such a way that it be directed along the conductor axis and will have a magnitude that satisfies Ohm's law in its local form.

So what happens with a superconducting wire?  Presumably the surface charges make the field inside the wire zero.  So what makes the current go?

Ah. Superconductors are quantum beasts. (Well, technically even ordinary conduction requires quantum theory to give quantitative agreement).
If we stay in the realm of classical ED, we can consider a perfect conductor as the limit of a resistive conductor for sigma->infinity. You need an infinitesimally small field to make the electrons move. But it can get tricky. Last year (?) Lewin posted a problem with a superconducting ring in a changing magnetic field. Basically what we call Lewin's ring but without resistors. What will happen? Only two people, among all those who were exposed to the problem (and they included several physics professors to which Lewin had emailed the problem) gave the correct solution. One is a professor in a University in Switzerland (IIRC) and the other is George Hniatuk (he has a youtube channel).

The solution is: no current inside the superconducting ring.

I had it wrong: my initial assumption was that the current would rise so rapidly - being a superconductor - that the small self inductance of the ring would act as a current limiter.  Then I saw George Hniatuk's comment (Nope. No current inside) - and knowing how he knows EM - I realized he was right. (Math and Physics are different - in math you can create the induced electric field magically inside the superconductor, in physics you must justify its presence there. How do you place it in? Surface charge will redistribute in such a way as to prevent it from entering the ring).

But this is not the reason I am telling you this. In the video (I will add a link tomorrow, now I need to sleep), or in the comments, Lewin made a very interesting statement. That to initiate a current in a superconducting ring you need... a resistor. You start your magnetic mumbo jumbo with the resistor inserted - and it's the field in the resistor that makes the electron go - once in the superconducting material they continue 'by inertia', and only after the current is established, you switch to a full superconducting ring.

Pretty crazy, uh?

Lewin did a bit of a mess, and the question is easy to anyone who knows superconductors.
The solution is: there'll be a current inside the superconductor.
No one said "E=0 in a superconductor" for the last 90 years, cf. https://en.wikipedia.org/wiki/London_equations
Of course, there's such a thing called "skin effect" which is a bit more extreme in superconductors, so that the current will be concentrated within a London length, or less than a µm. This is always true (at low magnetic field, type I etc.), whether you put a resistor with the superconductor or not.

So what makes the current go: either you inject electrons from a normal conductor (and you can then close the superconducting loop after if you want), or you bring a magnet close.

[Sredni]

So what makes the current go: either you inject electrons from a normal conductor (and you can then close the superconducting loop after if you want),

Which is what I wrote above: you need a resistor (the finite conductivity conductor).

or you bring a magnet close.

And there will not be current or field inside. Basically the current due to the surface charge that kills the field inside is all you get in a superconductor. In classical electrodynamics we can consider an impossible sheet of current of zero thickness (we can also consider infinitesimal charge quantities, if we wish). In the real world, in a real superconductor, the surface current will be confined to a few atom layers. But this is a far cry from stating that there is a current inside. That fraction of a micron is the real world approximation of the zero depth surface sheet.

There is a discussion of the difference between perfect conductors and superconductors in Ramo, Whinnery, VanDuzer (sec. 13.4 Perfect conductors and superconductors, p. 676 on the second edition).

Anyway, I found the links to Lewin's statement of the problem:



The solution



And further discussion