[amalia (OP)]

Rakesh reached out with a couple of questions on electric current:
What is the speed of electric current? When elections flow - do they come out from the atoms and flow as electric current? Is it not true that when electrons come out from atoms, light and energy is released? So why don't electric wires change their color?
Can you help?

[Kryptid]

Yes, the electrons come from the atoms in the wire. No, it's not true that light and energy is released when electrons come out of atoms. The opposite is true. Removing an electron from an atom requires the input of energy, not the release of energy. It isn't proper to think of the electrons as "coming out" of the atoms when electric current is passed through a wire anyway. The valence electrons are already distributed between many atoms as an "electron sea". The electrons are simply moved or vibrated through this sea when an electric current is applied.

If by "speed of electric current" you mean "drift velocity", then it's actually very, very slow: on the order of micrometers per second: https://en.wikipedia.org/wiki/Drift_velocity The electric signal itself can travel close to the speed of light.

[Soul Surfer]

Amelia,   Kryptid has given a good reply but I think that there is one more vital fact to get over.  The electrons associated with atoms that are bound together in the form of liquids solids or compounds behave very differently fro the electrons associated with atoms that are on their own in empty space as gases.  This is where the changes in energy levels can produce the emission of electromagnetic radiation including light.

When elements and compounds are in the liquid or solid state the electrons in the outer shells of the atoms are in effect linked to form the physical and chemical bonds that hold the atoms together.  These bonds can take several forms and this has a great bearing on the properties of the solid or liquid. 

In some substances they are locked together solidly in a formal pattern and this creates hard insulators that can be transparent like glass and diamonds. 

Sometimes they are freely moving and this creates metallic conductors like copper and aluminium  that can also  be soft and formed to shapes. 

The really interesting ones are the ones that are half way between these tow extremes  the semiconductors where with care the properties can be controlled by physical and electrical effects.  These semiconducting elements and compounds are the source of almost all of today's information technology.

[acsinuk]

It is not true that an electric current  is a flow of electrons through a conductor as electrons are particles and would take infinite energy to get to the speed of light.  However, magnons which can vibrate the magnetic flux inside a conductor electron shell enclosure and are capable of travelling at the speed of light, as an area of vibrating flux/current. 
This action can be witnessed in action in an isolation transformer in which the power passes from the primary winding to the secondary winding by linking the amp-turns flux areas together, by transmitting the energy through the iron core at the speed of light.

[evan_au]

an isolation transformer in which the power passes from the primary winding to the secondary winding by linking the amp-turns flux areas together, by transmitting the energy through the iron core at the speed of light.

Actually, the buildup of a magnetic field in the iron core is opposed by eddy currents formed in the iron core.
- This is a result of Lenz's Law: https://simple.wikipedia.org/wiki/Lenz%27s_law
- Eddy Currents (a flow of electrons) represent a major power loss in power transformers
- Designers of power transformers attempt to minimize this opposition and loss by making transformers out of very thin iron alloy sheets, with low conductivity between them.
- This means that the power in an iron-cored transformer is not transferred at the speed of light, but is in fact limited by design to the 50Hz or 60Hz of the national power grid.
- For high frequencies (eg in cellphones), transformers are made of non-conductive ferrites
- The worst possible design for a power transformer would be a solid iron core (which is implicitly promoted by the quoted statement above)

magnons which can vibrate the magnetic flux inside a conductor electron shell enclosure and are capable of travelling at the speed of light, as an area of vibrating flux/current.

I must say that "magnon" was a new term to me.
- But, like superconductivity, it is an effect that only occurs near absolute zero
- Magnons cannot account for power transfer in room-temperature transformers
- Magnons cannot account for power transfer in room-temperature copper wires
See: https://en.wikipedia.org/wiki/Magnon

It is not true that an electric current  is a flow of electrons through a conductor as electrons are particles and would take infinite energy to get to the speed of light.

This is confusing the movement of an individual electron with the propagation of an electric field.
- In a copper wire at room temperature, the individual electrons don't move faster than about 1mm/second, on average
- Even if you increase the current up to near melting point (ie considerably above "room temperature")
- The reason for this is that electrons continually bump into the copper atoms, and lose energy (which is what heats the wire). There is no suggestion that the individual electrons reach relativistic speeds in a copper wire.
- If the wire is carrying AC power, the electrons don't actually depart from their original position by more than the width of a human hair


It's a bit like the "Newton's Cradle" toy: if you hit one end with a swinging ball, the impulse propagates at a very high speed through the balls, even though the balls themselves hardly move.
- An electric field in a copper wire propagates at about 2/3 the speed of light (depending slightly on the geometrical construction of the wire, and the type of dielectric/insulator used).

Just because a mains-power isolation transformer can work via magnetic fields (over a narrow range of frequencies) does not prove that electrons don't flow in copper wires
- After all, the primary and secondary coils of the isolation transformer work fine with electrons flowing through the copper wire

[PmbPhy]

Rakesh reached out with a couple of questions on electric current:
What is the speed of electric current? When elections flow - do they come out from the atoms and flow as electric current? Is it not true that when electrons come out from atoms, light and energy is released? So why don't electric wires change their color?
Can you help?

The electrons in a conductor exist in sea of electrons. They aren't bound to particular atoms.

[chris]

Nice answers; thanks all.

[Bored chemist]

If anybody thinks the answer to the OP's question isn't "yes" then they have to explain where else the electrons might come from.
Walmart?

[acsinuk]

The electric current is better understood as an area of flux-current or magnoflux which is magnetically spinning inside the conductors molecules. Electro-magnetic ray energy is composed of a magnetic vibration of flux which induces a current [amps] at right angles. also known as a magnon. If a voltage is applied in the 3rd dimension the inertia will cycle forward as electric light #energy #vibration #magnetic 

[evan_au]

like superconductivity, it is an effect that only occurs near absolute zero
- Magnons cannot account for power transfer in room-temperature copper wires
See: https://en.wikipedia.org/wiki/Magnon

The electric current... also known as a magnon

Please explain how a cryogenic magnon effect can explain electrical conductivity at room temperature.
- Or are you talking about a "magnon" that is different from Wikipedia's "magnon"?
- Or maybe you have discovered room-temperature magnons?

[Bored chemist]

The electric current is better understood as an area of flux-current or magnoflux which is magnetically spinning inside the conductors molecules.

No.
Just, "no".

[alancalverd]

Just to stir the pot and add to acsin's confusion, it is worth noting that the charge carriers in aluminium travel on the opposite direction to those in copper.

With tongue firmly in cheek I would suggest that this is why Al is used for high voltage grid transmission lines - the charge flows in the forward direction in your copper-based motors and computers, so we conserve electricity, prevent the earth's magnetons getting in a tizzy, and save the polar bears.

[PmbPhy]

Just to stir the pot and add to acsin's confusion, it is worth noting that the charge carriers in aluminium travel on the opposite direction to those in copper.

Since when? What are you suggesting that the charge carriers are?

[evan_au]

the charge carriers in aluminium travel on the opposite direction to those in copper.

I also found this statement puzzling.

Is this something to do with conduction by electrons (in copper) vs conduction by holes (presumably in aluminium)?
Conduction by holes certainly occurs in semiconductors (like doped silicon).
See: https://en.wikipedia.org/wiki/Electron_hole#Solid-state_physics

[alancalverd]

Yes. Al is an oddity among metals in having a positive Hall coefficient, so  that the "conventional current" (that flows from positive to negative) is actually conduction by positive holes.

[evan_au]

I found a list of Hall effect coefficients.

Most of the metals seem to have the same polarity (iron is opposite)?
See: http://it.stlawu.edu/~koon/HallTable.html

[alancalverd]

Where on earth did I get the idea that aluminum was anomalous? I've held it for at least 60 years! Oh well, thanks for the table - it does at least show that some metals exhibit hole conduction!

[acsinuk]

I agree!  " Please explain how a cryogenic magnon effect can explain electrical conductivity at room temperature.
- Or are you talking about a "magnon" that is different from Wikipedia's "magnon"?
- Or maybe you have discovered room-temperature magnons? "  Well, said Evan
What we need is at least 2 leading universities to investigate  magnons and define exactly what they are from a classical and quantum physics point of view.
I have defined them from an electro-magnetic point of view and you should note that because nothing can be at 0degK the double pyramid volume shape will always rotate due to the magnoflux spin effect and therefore appear to be a sphere.

[alancalverd]

Hey, that's a great idea. Think of a word, then pay a bunch of academics to tell you what they think it means.

I think you have just invented theology.

[acsinuk]

Wiki says " The concept of a magnon was introduced in 1930 by Felix Bloch[1] in order to explain the reduction of the spontaneous magnetization in a ferromagnet."  So it is known for 90 years so why is it not clearly defined by physicists as a force carrier with its associated spinning amp-flux characteristics??