DCAudioDIY.com

This is one of the question which always bothered. I was never comfortable with the concept that electrons are moving at near the speed of light in cables carrying charge.

Watch the video below. It clearly shows that electrons ARE NOT responsible for carrying charge.

https://youtu.be/bHIhgxav9LY

How are the electromagnetic wave propagation and electron discharge in vacuum tubes related to each other.

What I learned -- or should I say was taught -- electrons do not "flow" but are displaced. A mechanical demonstration of this effect can be done with billiard balls. Line up a straight string of balls on the table then take one ball and use it to strike the first ball.

There is no flow or movement of the balls, but the ball at the opposite end of the string is bumped out of position. Kirchhoff's Current Law applies here, which states that “The algebraic sum of all currents entering and exiting a node must equal zero.”

This law is used to describe how a charge enters and leaves a wire junction point or node on a wire. This also is similar to "hole theory" in terms of describing the behavior of transistors (solid-state).

Using the term "flow" kind of simplifies the issue in the minds of most people since an analogy could be water flow. Pressure = Voltage Flow = Current

_________________
Walt

Shashi,

Interesting video, thanks for posting. Actually, the influence of cable capacitance in the first transatlantic cable is an interesting example of how cable construction affects signal performance...there is a scientific reason why cables may perform (and sound) different.

Electron tubes introduce a different element into the equation. They depend on thermonic emissions of free electrons from the surface of an emissive material such as Thorium, Tungsten, oxides of Barium, Strontium heated to a high temperature. This is a case where electrons *DO* flow in free space. The plate attracts the flow of electrons due to the high potential (a field effect?), and the field created by the signal in the grid interferes with (modulates) this flow of free electrons. A strong enough field will block the flow, a weaker field will allow electrons through. At least that is my understanding.

David

Electrons and photons experience actions that mimic both particles and waves. The difference is electrons have charge and photons do not. Using light from the sun as an analogy to electrical flow is therefore not entirely correct. His video is another way at looking at the effect of electrons and energy transfer. Although energy is transmitted in the electric and magnetic fields, it is the movement of electrons that creates the magnetic fields. That is why if no electrons move, no magnetic fields are created and while you have a situation that may have a significant amount of potential energy, it is not until the electrons move and create the magnetic field that you get kinetic energy.

BTW, the electrons do move at the speed of light. However, when you look at the fact that an electron moves to an adjacent atom in the conductor, there are so many atoms that the single atom would take a very long time to travel down the wire even at the speed of light if it is a DC situation. The effect of that one electron moving to an adjacent atom at the speed of light pushes an electron off the adjacent atom and the process repeats down the length of the conductor., thus moving the energy at the speed of light.

The effects of the conductor parameters such as resistance, inductance, and capacitance are ways that can be use to describe the modifications of the energy transfer along the wire. As far as we are concerned, it is not necessary to get into the bowels of the laws of physics to make an audio system work at a basic level. The details do make a difference when you get to the highest levels of performance, but you can still use the parameters described to work with a system. And, of course since your brain does not function like a simple conductor or electrical component, at the end you have to listen.

On a totally different subject, all matter in the universe (ignoring dark matter for the moment) is considered baryonic matter and the baryonic particles that make up matter such as atoms according to some are simply packets of vibrating energy. My string theory is lagging so by now I may be off base. That is why I stick to the basic parameter when working with audio.

Poor dumb me just listens in ignorant bliss and is perfectly happy to float along in the wonder of music.

_________________
Walt

In a vacuum tube, the electrons are freely flowing (lets ignore the direction of flow of charge in the tube for now). Once the free electrons reach the anode, what happens to them? Do the electrons attracted by anode enter it and flow thru the anode circuit? According to the video, the electrons drift at 0.1mm/sec in a conducting medium where as the charge (electrical and magnetic) flows at speed of light.

The electrons are travelling at near the speed of light in the vacuum tube until they reach the anode, but in the anode circuit, they drift at only 0.1mm/sec. Wont this huge difference in velocity cause the anode to saturate with electrons?

_________________
Walt

That Veritasium Video on electricity is causing a big debate.

RSD Academy has posted a video to explain the science behind Veritasium video. It is a very simplified version which deals it at the level of simple electronic devices like capacitors and transformers where as the original video is dealing at strictly electromagnetic propagation. It feels short IMO.

https://www.youtube.com/watch?v=--v5BXmFYv4

I think my question was answered in the RSD academy video. Even though the electrons are only drifting at 0.1mm/sec inside a conducting medium, the electrons act like longitudinal waves transferring energy to the electrons in front of them at nearly the speed of light.

The red plating is caused by improper/faulty circuit, but that's not directly related to our discussion here.