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

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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:

--- Quote from: Sredni on June 22, 2022, 04:53:29 pm ---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

--- End quote ---

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:

--- Quote from: electrodacus on June 22, 2022, 06:09:58 pm ---
--- Quote from: Sredni on June 22, 2022, 04:53:29 pm ---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

--- End quote ---

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


--- End quote ---

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:

--- Quote from: Sredni on June 22, 2022, 06:31:38 pm ---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.

--- End quote ---

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:

--- Quote from: Sredni on June 22, 2022, 04:53:29 pm ---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.

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

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