connect 2 different wire gauge to pos and neg speaker terminal

Geoffkait 9-2-2-2017
Uh, I’ve already stated that it’s a tie. As indicated by the mathematical paper from the Journal of Physics on the dodgy subject of whether the energy of the signal is located outside or inside the conductor the energy is actually partly outside and partly inside. And the mathematics for that conclusion is provided in the first couple of paragraphs. Don’t tell me you didn’t read it. GASP

Yes, I had read the paper you are referring to.  There is nothing in it that is inconsistent with what I have said.

If you'll notice, it deals with a hypothetical situation in which the wire ***is*** the load.  In other words, a single piece of "long" wire is connected directly across the terminals of a voltage source.  (The numerous references in the paper to the wire being "long" presumably imply that its resistance is high enough to limit the resulting, um, current, to an amount that can be provided by the voltage source, and that would not cause the wire to melt).

In that situation the Poynting Vector would point inward to the conductor, at all points along its length, as shown in Figure 1 of the paper.   The energy carrying photons would therefore enter the conductor, causing the conductor would heat up.  Note the references to energy flowing **into** "the cylinder," resulting in "Joule heating."  "The cylinder" referring to the geometry of the wire.  As the paper says:

The picture that emerges from these considerations is that the electromagnetic field around a current carrying wire is such that the energy dissipated in the wire is brought into it by the corresponding Poynting vector through each point of its surface.

That is all perfectly consistent with what I have said on the subject previously, assuming a more real world scenario involving low resistance wires conducting energy to a resistive load.  In that situation the electromagnetic wave, and the photons comprising it, travel outside the conductors, aside from (as I said in my previous post) "the very small fraction of the photons corresponding to the very small amount of energy that is absorbed by the resistance of the conductor and converted to heat."

Regards,
-- Al
  

Kijanki wrote,

Drift velocity is average electron velocity since it is "net" axial velocity in one direction while electrons move in different directions.

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

Fermi velocity (random) applies only to materials when no current is applied. As I stated previously the very low Drift Velocity indicates that electrons do not (rpt not) travel rapidly at any time in the conductor. If they did the net velocity or average velocity whatever would be much higher than the centimeter per hour velocity observed.

Pop quiz, if electrons are changing direction with alternating current, why is there a net velocity in one direction along the axis? Shouldn’t there be zero net velocity? And why is the net electron velocity in one direction, not the other direction? Why do electrons favor one direction over the other, assuming vector of Drift Velocity is always in the same direction?

Geoff, re your pop quiz, as you appear to realize there is no **overall** net movement of the electrons, assuming that the DC component of the applied voltage is zero. However, within each half-cycle of the applied voltage there is net electron movement and net velocity in one direction or the other, the direction corresponding to the +/- polarity of the applied voltage at that instant. I had said that in one of my early posts in this thread.

Also, I believe that your statement that "Fermi velocity (random) applies only to materials when no current is applied" is incorrect, and that there is always random movement of some electrons, at Fermi velocity and in random directions. That is why the word "net" comes into play. Since the movements at Fermi velocity are in random directions, that velocity does not factor into (or average into) the drift velocity.

Regards,
-- Al

Therefore in this wire the electrons are flowing at the rate of 23 µm/s. At 60 Hz alternating current, this means that within half a cycle the electrons drift less than 0.2 μm. In other words, electrons flowing across the contact point in a switch will never actually leave the switch.

You’re talking AGAIN about electrons. Electric current moves with the speed of electric charge (electric field) and not the speed of electrons or drift velocity. When you flip a switch electric charge moves thru conductor at the speed of light (remember stacked balls?) magnetic wave follows at the same speed. If electric current moves at the drift velocity then in very long cable electrons at the end would not even move since it would take hours or days for charge to get there. All electrons along the wire move together instantly like stacked balls. Electric and magnetic fields have to move with the same speed (electro-magnetic field) because one doesn’t exist without the other. Again, imagine pipe filed with ping-pong balls. When you push them at one side of the pipe they will start coming out at the other instantly. When there is no change (DC) electrons move at drift velocity. DC current is proportional to drift velocity while drift velocity is proportional to magnitude of electric field. Any sudden change at the one end of the wire will travel thru the wire at the speed of light and it will arrive almost instantly and not a few days later. It will travel as wave of electric charge inside of the wire (stacked balls) and wave of magnetic field outside of the wire at the same light speed (or close to it).