Directionality of wire

In the case of an electrical signal (or AC power) that is being conducted via wires the energy is conveyed in the form of an electromagnetic wave, which travels outside the conductor itself. That wave propagates at a substantial fraction (generally somewhere between 50% to 98%) of the speed of light in a vacuum. The exact speed depends primarily on the "dielectric constant" of the particular insulation.

Any electromagnetic wave can be considered to be comprised of photons, although the term photons is most commonly associated with a particular kind of electromagnetic wave, namely light.

As I indicated in an earlier post in this thread, in the case of an electrical signal that is being conducted via wires the near light speed propagation of that electromagnetic wave is intimately related to movement of electrons within the conductor, even though that electron movement occurs at a **vastly** slower speed.

Sfroyen’s comment that "the energy flow takes place in the dielectric surrounding the conductors -- including the surrounding air" is absolutely correct. Photons do not travel within metallic conductors, electrons do. Ralph (Atmasphere) has made the same point, btw, in prior threads here that have involved similar controversies.

Regards,
-- Al

fsonicsmith seems too informed and rational to post on this thread

he might as well be quoting Patti's favorite French poet here

same for almarg - BTW, it is obviously the neutrino flux interacting with the wrong way wire

There is some confusion as to what the difference is between current and the audio signal. The audio signal is the electromagnetic wave. The current is traveling at the speed of electron flow in the conductor, which is virtually idle, to whit,

"Electromagnetic waves propagate in vacuum at a maximum speed of 299,792,458 meters per second . For a 12-gauge copper wire carrying a 10-ampere DC current, the speed of electric current (average electron drift velocity) is about 80 centimeters per hour or about 0.0002 meters per second."

The electromagnetic wave is the audio signal. There is no electromagnetic wave in the power cord or in the fuse where the power cord enters the amp. As I said previously, most audio frequencies travel within the IC or speaker cable wire per se, the skin effect being that very high frequencies travel nearer the surface (skin) of the metal conductor. And what carries the audio frequencies? The electromagnetic wave, of course!

There is no law saying photons can’t travel in copper. In fact it’s the physical non symmetry of the copper ITSELF that gives rise to directionality. Now, if anyone wishes to argue that "directionality" is due to electron speed differences (due to physical non symmetry of the wire) that give rise to resistance differences depending on directios I might actually consider going along with that.

geoffkait

There is no law saying photons can't travel in copper. In fact it's the physical non symmetry of the copper ITSELF that gives rise to directionality. Hel-loo!

>>>>>Indeed there is. The laws are called Maxwell's equations and were published in the 1860s. They are fully relativistic and form the basis for all electric, optical and radio technologies. In fact they are also used to calculate the skin-effect. As I stated above, any asymmetry in the copper can only affect the electron motion -- not the photons (electromagnetic fields and photons are one and the same).

If somebody is interested in the math of electrical energy flow in cables, this is a good article in Am. J. Phys. (it's possible to read the paper without following all the math):

http://depa.fquim.unam.mx/amyd/archivero/El_flujo_de_energia_de_una_bateria_a_otros_elementos_de_un_...