Electric charges part 1 longitudinal wave propagation

  • Last Post 30 January 2023
Vidura posted this 21 May 2022

This thread is a copy from the proboard forum. As the topic is important for understanding the principals of propagation of electric energy I decided to publish again in the new site. Eventually some details will be corrected by the way.

This thread will be dedicated to longitudinal waves and the related phenomenon's of physics. As an introduction I would like to remind you that the human brain has two hemispheres, each one dedicated to a specific kind of processing information. Nowadays the term knowledge is uniformly associated with the accumulation of information, and it's processing with a kind of binary logic. This capabilities are mostly located in the left hemisphere of the brain, in contrast the capacity to understand by the way of analogies , images and intuition are domains of the right hemisphere of the brain. There is certainly a insane unbalance of this capabilities in the present time, as from early stages of the educational system there is paid attention almost exclusive to the "left hemisphere intelligence", while the other side is left to its own, without any training in most cases. In order to develop the whole potential of our intelligence-knowledge, it is necessary to train both sides of our brain with their associated capabilities, as they are a conjugate pair. This will require some practice and time, but finally it will enable us to gain an integral understanding of the phenomenon's of the physical world and beyond, and transcend the limited "binary logic way of thinking" . This is the reason why we will use analogies of the properties of sound-waves in this topic, as it will help us to get a better visual and intuitive understanding of the electrodynamic equivalents.
First we will have a look at the properties of a sound-wave inside a tube, and analyse the processes in detail.
We will be discussing only the simplest form of waves (called linear waves). Most sound waves behave as linear waves since they produce pressure fluctuations in air that are very small compared to the atmospheric pressure. This will be sufficient for the beginning, as it represents quite good the basic behaviour of our analogy, which will be an electric conductor(long line).
Waves transfer energy without transferring matter.
Let us consider air particles set in motion by a vibrating piston. We can see that the particles (the black dots in the animation below; three of these have been coloured red for illustrative purposes) move back and forth about their equilibrium position, thus creating alternating zones of compression and rarefaction. In the rarefied region, the pressure is less than the normal undisturbed atmospheric pressure, denoted Patm, and in the compressed region, the pressure is greater than the normal undisturbed atmospheric pressure, as shown in the animation below. 

As you can see, it is the disturbance which travels, not the individual particles (if in doubt fix your eye on one of the red particles). In sound waves, also known as acoustic waves, the local oscillations always move in the same direction as the wave. Waves like this are called longitudinal waves.
The velocity of a wave in a given medium (air, water, etc) is fixed and is related to the physical characteristics (temperature, density, etc.) of the medium.
But the frequency and thus the wavelength and the amplitude of the difference of pressure are dependent on the source, in our example from the movement of the piston.
For greater clarity, I selected key frames from this animation, which captured the individual stages of the red piston movement and the resulting deformation of the elastic air. Let's analyze them.

Below in the image, the piston (sound source) is on the left (at the bottom dead center) and starts moving to the right with some acceleration.

When the piston moves to the right, air molecules condense in front of the piston, increasing the pressure in front of it (despite the tendency of the molecules to scatter in different directions).

In the upper image the piston continues its movement, forming condensations of molecules in front of it.

In the middle frame the piston continues to move, but already with maximum speed, and the wave of compression of molecules (but not the molecules themselves) in front of the piston continues to grow.

In the lower frame the piston stopped at the top dead center, forming a maximum concentration of molecules in front of it, after which the longitudinal wave, under the action of inertia, continues to move independently along the air channel at a constant speed.


Vidura posted this 28 January 2023


Hi Vidura.
A complex material for most of us I think, but a good analogy with sound propagation.
If we were to extrapolate a little... do you think it would be possible to give an example of a circuit, device, etc. which can be achieved? What do you think about the caduceus coil, for example. Would it fit in here?
In any case, it is one of the few articles that deal with this subject.
Thanks. Felicidades!!!

Thanks for the feedback. Yes it is a bit complex, but by means of analogies it can be intuitively understood, it might need some training, but if you get the "feeling" of the behavoir of waves it helps a lot. The caduceus coils I have not yet tested, somw weird things are stated about them, would be interresting to verify. For the question about a circuit or device that can be achieved, I think many of them will be built,  and  wave theory is needed for most I believe. 



Vidura posted this 29 January 2023

Hi all, I made some corrections in the earlier posts and added content, for those who are interrested might want to review.

Regarding the 20nS delay in the video, I found the cause. A wireloop like shown in the experiment is equivalent to a transmissionline with shorted endpoint. The voltage on the second end would appear immediately, but there is a delay as the energy wave reaches there along the wires of the scopeprobes, and the signal has to travel back to the scope. Note that this signal (Ch2) has half of the potential applied from the SG. This is in accordance with Ivor Catt's theory. The actual propagation velocity when the signal reaches the full potential, was exceeding 40nS. So the physical laws are still valid😂.


Atti posted this 29 January 2023

 A wireloop like shown in the experiment is equivalent to a transmissionline with shorted endpoint.


Now I am not writing about the propagation speed of the signal, but about its effect.



-Wave reflections.
Special cases when the wave suffers a phase jump.
Let's think here of the stretched end of the rope. Phase jumps of the free-end rope end or the clamped rope end. (transmission line)
-For example, opposing magnetic fields.
- Or the electromagnetic waves moving against each other.
The interference phenomenon created in this way and the reflection itself cause many interesting things.




For the question about a circuit or device that can be achieved, I think many of them will be built,  and  wave theory is needed for most I believe. 

Yes. We are working on it.


Otherwise, an example.



So. We have a transformer. With a specific control, a secondary circuit. If we have another control circuit and if the "parameters" of the two controls are the same, then nothing special happens. (Think about the parallel operation of the transformers here.)
But if the parameters are correct, one source fills the other source. Then exchange.

In this video, both power supplies start at 20 volts.
At first, the excitation is small, so the bulb does not light up.
If there is a suitable resonance, the other power supply is charged to 30 volts and the bulb also lights up dimly.
Then exchange.
The change in the direction of the current is shown by the double-sided Deprez meter.

The situation is similar for multi-transformer solutions. It is true that the capacitor between the two transformers provides reactive energy. This reactive energy travels between the two transformers.
In the description of the fourth video, I refer to the previous videos. This way you can jump back with the search.But this is just my opinion.











First measurement is not a measurement. Second measurement half measurement. Third measurement is a measurement.

Vidura posted this 30 January 2023

In the following post I will show some tests of measurement of the wave propagation, which I think could be helpful for those who are building on replications.


In the video below it is clearly demonstrated that the propagation velocity of a longitudinal wavefront depends on the distributed capacitance of the line:

If you think about the implications for practical works, you will note that it is necessary to make measurements for an accurate tuning of oscillatory circuits. With calculations, despite they are done correctly, will at best lead to an approximation. It also becomes clear, that not the speed of light should be used by default for this calculations, as it only applies to thin wires suspended in air at a considerable distance from the ground(or the second conductor). Therefore, if we need a accurate tuning between different oscillatory circuits, especially if different types and gauges of wire are used, then we need to make measurements with all coils and components mounted in its final position.   For tuning the longitudinal resonance with the magnetic resonance of a conductor in one and the same coil, the best way is to do the longitudinal velocity measurement first, also everything mounted in its position, and then calculate the resonant frequency. Then we choose a constructive related frequency(harmonic) for the magnetic resonance and adjust for example by adding a ferromagnetic core material for the final tuning.