Some have claimed that the speed of electricity is quite slow and varies with the frequency of the alternating current. The disconnect seems to be with the definition of "electricity."
We know from years of talking on wired telephones and using a synchronized power grid, that DC, 50/60 Hz, audio, and radio frequency signals flow through a wire at 50 to 90% of light speed. The frequency of the signal does not appear to be a major factor in this speed. In some instances very high frequencies (several GHz) may be slightly slower than audio due to a lossy medium being used as the insulator, not the conductor.
As I stated previously that if the wire was long enough an individual electron may never make it out the other end, just be pushed back and forth. If it is somewhat shorter than this critical length an electron may get smacked back and forth a zillion times but moves a very tiny distance forward with each smack, making it's apparent movement quite slow. Repeat the smacking more often (raise the frequency) and this movement will appear to speed up.
Place all of the billiard balls against the rail along one side of the table. Drive the cue ball into one end of this row, and the last ball will pop out from the end. All the balls in the middle will move a tiny amount. The ball that left the end will be moving at the same speed as the cue (minus frictional losses) but those in the middle move in small quanta. This makes the apparent movement of the stack rather slow, and dependent on several variables.
We know from years of talking on wired telephones and using a synchronized power grid, that DC, 50/60 Hz, audio, and radio frequency signals flow through a wire at 50 to 90% of light speed. The frequency of the signal does not appear to be a major factor in this speed. In some instances very high frequencies (several GHz) may be slightly slower than audio due to a lossy medium being used as the insulator, not the conductor.
As I stated previously that if the wire was long enough an individual electron may never make it out the other end, just be pushed back and forth. If it is somewhat shorter than this critical length an electron may get smacked back and forth a zillion times but moves a very tiny distance forward with each smack, making it's apparent movement quite slow. Repeat the smacking more often (raise the frequency) and this movement will appear to speed up.
Place all of the billiard balls against the rail along one side of the table. Drive the cue ball into one end of this row, and the last ball will pop out from the end. All the balls in the middle will move a tiny amount. The ball that left the end will be moving at the same speed as the cue (minus frictional losses) but those in the middle move in small quanta. This makes the apparent movement of the stack rather slow, and dependent on several variables.
I very much doubt those distinguished Gentlemen could repeat the feat in a proper double blind experiment.
Seeing and believing does not make something true.
John Edward reading - YouTube
NO speaker has exactly 8 ohms, except by chance and only at a single frequency or two, if that were a problem,*all* amps would distort all the time.
Not sure why this relates to speakers having exact 8 ohm or not, or distortion.
We are talking Equal length wiring, not short/long same length in this thread
[/QUOTE]:where is the problem to desing something evenly, that whatsoever no chances are taken that because of not distribuiting Current Voltage, energy evenly, will bring up problems. Even if don't matter as you guys write, OK with me, but I do not like to TAKE CHANCES and then to find out, why afterwards instead of listening and enjoy music which is played, sound is like a trash can.!.. [/QUOTE]
Such GROSS deficiencies do not come from different length wiring in any normal installation or build. Search for other motives.
Maybe, but because way too much inductance, capacitance, poor layout or grounding, not because of "different length" or 1.5 meter vs 5 meter length.
But in 3 meters wen have a Trillion Billion Zillion Atoms, not just "100"
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Even if we focus on the movement of one electron, there is no guarantee that after it moves it will move again, a different electron from the next atom may move instead.
And if it is AC, the current reverses from time to time, the electrons will ping pong and most likely never traverse the entire lenth of wire, as tubelab says.
Also we are ignoring the fact that the wire whose length you want to match may be exposed to differing interference or noise if you make it a matched length, proving to be detriment over nonmatching lengths that are separately and independently routed carefully to avoid noise or inference pickup.
And if it is AC, the current reverses from time to time, the electrons will ping pong and most likely never traverse the entire lenth of wire, as tubelab says.
Also we are ignoring the fact that the wire whose length you want to match may be exposed to differing interference or noise if you make it a matched length, proving to be detriment over nonmatching lengths that are separately and independently routed carefully to avoid noise or inference pickup.
If we try to follow one electron through a wire it takes a relatively long time. But current is not a bunch of electrons entering one end of a wire and traversing it. If we bang one electron into one end of a wire, a different electron pops out the other end, the distance covered at close to the speed of light.
Back in the day of RGB video we would have to match cable length within a quarter of an inch between each RGB coax. Longer than that would screw up the timing and colors would look like the tiktok logo, offset. That was at MHz frequencies. At audio frequencies several inches will not cause enough delay to be audible. There are much more important things to worry about in life and in amplifiers.
"Electricity" doesn't move. Electrons and EM waves move. We used to make 5000 mile phone calls over copper cables. If you can't come to a logical conclusion from that theres no hope.
"3.1m/s. As a consequence of Snell's Law and the extremely low speed, electromagnetic waves always enter good conductors in a direction that is within a milliradian of normal to the surface, regardless of the angle of incidence. This velocity is the speed with which electromagnetic waves penetrate into the conductor and is not the drift velocity of the conduction electrons."
This is the speed the EM waves enter the conductor. (no EM waves in a perfect conductor, the electrons move to cancel it) and I think the skin depth is how far they penetrate. The speed of the EM waves outside the conductor is near the speed of light. The copper carries the electrons the dielectric carries most of the EM field.
This is the speed the EM waves enter the conductor. (no EM waves in a perfect conductor, the electrons move to cancel it) and I think the skin depth is how far they penetrate. The speed of the EM waves outside the conductor is near the speed of light. The copper carries the electrons the dielectric carries most of the EM field.
From Poynting vector - Wikipedia
Coaxial cable
Poynting vector in a coaxial cable, shown in red.
For example, the Poynting vector within the dielectric insulator of a coaxial cable is nearly parallel to the wire axis (assuming no fields outside the cable and a wavelength longer than the diameter of the cable, including DC). Electrical energy delivered to the load is flowing entirely through the dielectric between the conductors. Very little energy flows in the conductors themselves, since the electric field strength is nearly zero. The energy flowing in the conductors flows radially into the conductors and accounts for energy lost to resistive heating of the conductor. No energy flows outside the cable either, since there the magnetic fields of inner and outer conductors cancel to zero.
Counter intuitive but most of the power delivered by cables doesn't run thru the conductors.
Coaxial cable
Poynting vector in a coaxial cable, shown in red.
For example, the Poynting vector within the dielectric insulator of a coaxial cable is nearly parallel to the wire axis (assuming no fields outside the cable and a wavelength longer than the diameter of the cable, including DC). Electrical energy delivered to the load is flowing entirely through the dielectric between the conductors. Very little energy flows in the conductors themselves, since the electric field strength is nearly zero. The energy flowing in the conductors flows radially into the conductors and accounts for energy lost to resistive heating of the conductor. No energy flows outside the cable either, since there the magnetic fields of inner and outer conductors cancel to zero.
Counter intuitive but most of the power delivered by cables doesn't run thru the conductors.
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In a metal the electrons all move (or rather drift) in concert - as shown by the lack of shot-noise in metalic conductors. Basically they are all working together bound by the electric field within the metal. The drift that forms the macroscopic current is superimposed on the thermal jigging of the electrons.
Typical speeds in a copper wire:
electric field propagation along the conductor - close to 300,000,000m/s
typical electron drift speed at moderate current densities ~ 0.0001m/s
thermal jigging at room temp - 1,600,000m/s (more properly the Fermi velocity)
Number of free electrons in 1mm cube of copper: 85,000,000,000,000,000,000
(or ~14 coulombs)
I'm avoiding scientific notation to highlight the vast numbers and different scales involved...
In my day, I did some lossless line RF measurements. If you match the Rload and the amp o/p impedance load along the best cable you can get. If there are any load mismatches the reflections & timing delays are really noticeable. i.e. the amplitude of the reflection is subtracted from the main output level.
Therefore with audio lines, I'll let you slug it out as I haven't tried the lossless method yet.
Therefore with audio lines, I'll let you slug it out as I haven't tried the lossless method yet.