none related off topic posts

[Chet K]

http://rexresearch.com/corumzenneck/texzon.pdf

Just one link

[F6FLT]

Wow, I'm surprised to see so many references to Dollard, Steinmetz, and Farnsworth in a NASA-sourced paper
How'd you even come across it?


F6FLT, you might be interested in Section 3.3 "Differences Between Longitudinal and Transverse Electric Waves."
(PDF pages 60 to 67)

I can confirm the effects in Fig.8 A-D by firsthand experience.

In 2004, NASA had launched a vast exploratory project on alternative technologies, and was open to exotic theories, the goal being especially to imagine innovative propulsion methods.
I'll leave out the suspense about the result: nothing came of it (even the EM drive turned out to be a failure).
Then you will notice that on the pages indicated, it is always said "The BSRF experimenters claimed...". It is not NASA that "claims". NASA simply reports, it has never taken on board all these exotic theories. And it was right. When you see the images on the page marked "50" (actually page 64 of the PDF), you understand that the BSRF experimenters did not understand what they were observing.

At the end of the electric wire, there is a strong gradient of electric field. When we approach the finger or an object, it is subjected to this field gradient and therefore to a force towards the terminal of the wire. It is, in the electric domain, the same phenomenon that we have in the magnetic domain when a flat coil carrying a current is attracted by another close one. If the current is alternating, it doesn't change anything because it is in both coils that the current changes direction, so the force remains in the same direction.
Here in the electrical domain, the strong electric field at the end of the wire attracts the opposite charges of the object that is presented nearby. If the field is alternating, the force is always of attraction since the charges induced in the object are always of opposite sign to those at the end of the wire.
The explanation for the charge on the nearby capacitor is obvious: the field ionizes the air, and since the ionization is greater on one side of the capacitor than on the other, it becomes charged.

The attached diagram explains what the proponents of the longitudinal wave want to see, compared to what engineers with some experience, especially those in the RF field, see.
Longitudinal wave proponents see only appearances: a wire with nothing at the end.
Engineers who have a little experience see the capacitance at the end of the wire, the one that any conductor has in relation to the ground and to the other conductors in the vicinity, and never ignore it in their calculations (that's why they shield the RF circuits). This capacitance, associated with Maxwell, explains everything about single wire transmission currents, and for the electric field, see my explanation above by the gradient.

[Hakasays]

It is not NASA that "claims". NASA simply reports, it has never taken on board all these exotic theories.

I still found it impressive that NASA would be open at all to alternative models/theories/experiments.

And it was right. When you see the images on the page marked "50" (actually page 64 of the PDF), you understand that the BSRF experimenters did not understand what they were observing.

It was decent by 80's fringe-science standards but certainly not for today.
Adrian does a far better job scientifically in his replication: https://www.am-innovations.com/teslas-radiant-energy-and-matter-part-1/

At the end of the electric wire, there is a strong gradient of electric field. When we approach the finger or an object, it is subjected to this field gradient and therefore to a force towards the terminal of the wire.

The fields/rays generated by the Borderlands-style disruptive discharge setup are attractive to metals but repulsive to other things.

By-hand, it feels as if there is a very thin layer of soft 'rubber' or gel covering the bulb when the devices are in operation.
This rubber-like field felt by the hand expands and contracts slightly in-sync to the somewhat irregular spark discharges.

In addition, while the filament becomes hot in one-wire operation it visually appears different.  One will see straight, needle-like arcs emanating in all directions from the filament that gradually become more dense and numerous as the power is increased.  At full power the emanations merge into a puff or 'cloud', that doesn't show up well on camera.  The light from the bulb appears pure white as a result, rather than the yellowish glow normally seen when the bulb is driven with AC or RF.

[Grumpy]

That is the same description as a bulb being powered (lit?) by "cold current", which has been defined very well.

Is there a transverse current and a longitudinal current that are two separate things or are they different manifestations of the same thing? (Second option sounds more likely.)

[Hakasays]

That is the same description as a bulb being powered (lit?) by "cold current", which has been defined very well.

Is there a transverse current and a longitudinal current that are two separate things or are they different manifestations of the same thing? (Second option sounds more likely.)

Personally I would go with 'two different forms of induction' since dielectric and magnetic fields can both separately transfer power across empty space.  Two separate elastic properties of space; permittivity+permeability.
And the properties of dielectric induction appear to differ significantly from magnetic induction (because why wouldn't they? ).

But for terminology, I personally think there are many terms describing the same exotic phenomena.
Capacitive coupling, 'cold electricity', dielectric induction, displacement current, longitudinal networks, are all focused on the dielectric over the magnetic.

[Paul-R]

I Googled NASA/CR-2005-213749 from SolarLab's post above.

Interesting and weighty document. But it is Voluime 2. Can anyone find the Volume 1? I can't find it on NTRS.

[Paul-R]

Interesting and weighty document. But it is Voluime 2. Can anyone find the Volume 1? I can't find it on NTRS.

This is Volume 1. Interesting refs to Bearden, zpe and lifters around page 90 (doc page 80 approx).

[F6FLT]

I still found it impressive that NASA would be open at all to alternative models/theories/experiments.

It didn't last, and for good reasons, the same ones that I ask for and that are missing, experimental evidence. They are still open but more selectively today.

It was decent by 80's fringe-science standards but certainly not for today.
Adrian does a far better job scientifically in his replication: https://www.am-innovations.com/teslas-radiant-energy-and-matter-part-1/

The fields/rays generated by the Borderlands-style disruptive discharge setup are attractive to metals but repulsive to other things.

By-hand, it feels as if there is a very thin layer of soft 'rubber' or gel covering the bulb when the devices are in operation.
This rubber-like field felt by the hand expands and contracts slightly in-sync to the somewhat irregular spark discharges.

In addition, while the filament becomes hot in one-wire operation it visually appears different.  One will see straight, needle-like arcs emanating in all directions from the filament that gradually become more dense and numerous as the power is increased.  At full power the emanations merge into a puff or 'cloud', that doesn't show up well on camera.  The light from the bulb appears pure white as a result, rather than the yellowish glow normally seen when the bulb is driven with AC or RF.

I do not understand. You still bring back bewildering interpretations and human sensations to evaluate physical phenomena. You get nowhere with subjectivity, and you fail in technology when effects are only supposed from doubtful, non-formalized theories.

Rather than listening to the opinions of others, which copy each other and have resulted in an implausible mythology around Tesla, one must make the effort to confront the real facts. In science, one takes the trouble to verify by measurement.
The beautiful speeches without formal logic or proven facts, everyone can make them, do not believe everything we find on the Internet. Why don't you use your skills in electricity and electronics to verify by measurements what people not necessarily more competent than you say, or even, which is more efficient, to base your own interpretations from your own tests?
I am talking about elementary tests at the beginning. And only then, if it works, do we move on to the biggest achievements like a big Tesla coil for Transatlantic Communication.

[solarlab]

It didn't last, and for good reasons, the same ones that I ask for and that are missing, experimental evidence. They are still open but more selectively today.

I do not understand. You still bring back bewildering interpretations and human sensations to evaluate physical phenomena. You get nowhere with subjectivity, and you fail in technology when effects are only supposed from doubtful, non-formalized theories.

Rather than listening to the opinions of others, which copy each other and have resulted in an implausible mythology around Tesla, one must make the effort to confront the real facts. In science, one takes the trouble to verify by measurement.
The beautiful speeches without formal logic or proven facts, everyone can make them, do not believe everything we find on the Internet. Why don't you use your skills in electricity and electronics to verify by measurements what people not necessarily more competent than you say, or even, which is more efficient, to base your own interpretations from your own tests?
I am talking about elementary tests at the beginning. And only then, if it works, do we move on to the biggest achievements like a big Tesla coil for Transatlantic Communication.

F6FLT

You make it sound like you work for, or contract with, NASA (bold/underline above).

What's your mail stop?

Maybe someone can point you to the information you asked for -

"the same ones that I ask for and that are missing, experimental evidence" (?).

Be specific, there are volumes available.

Regards, 

SL

[Hakasays]

I do not understand. You still bring back bewildering interpretations and human sensations to evaluate physical phenomena.

An honest scientist would not ask someone to ignore firsthand observations just because they disagreed with them.


F6FLT, did you read any portion of Adrian Marsh's paper that I linked above to see if it meets your scientific standards?
Or are you again making conclusions based on blind ignorance?

If you're not willing to approach these exotic subjects with an open mind, I don't think this forum is the right place for you.

[F6FLT]

I was very specific, explaining why the past experiments of longitudinal waves can be explained by radio waves or why the effects invoked in the "single wire transmission" are not exotic.

If we take as gospel what others have said or done and interpreted before us, it becomes useless to make experiments, we would only see what we want to see.
To experiment is not to become complacent in what we want to believe, but to question what is affirmed, to be sure. It is as well to question that it would be a radio wave, as to question that it would be a longitudinal wave.

The truth only comes out of the elimination of bad hypotheses.
This is why I proposed to make a radio transmission on the same frequency as the hypothetical longitudinal wave to distinguish the two.
This is why I made the proposal of a link on a path, a frequency, and a time where the radio wave cannot pass.

Obviously they had no echo, so any link with a Tesla coil is considered as proof of a longitudinal wave: it is the justification of a credo in an "exotic subject", which proves that the subject is "exotic" (we are going around in circles) and that those who have never found any reality in it, like ham radios, however great experimenters of waves, are not open-minded! 
I am not interested in non-scientific methods nor in esotericism.

[Hakasays]

I was very specific, explaining why the past experiments of longitudinal waves can be explained by radio waves or why the effects invoked in the "single wire transmission" are not exotic.

Performing experiments yourself, or speaking from third-hand knowledge again?

F6, I still await your results comparing transverse and longitudinal networks on the bench or with a circuit simulator.  https://www.overunityresearch.com/index.php?topic=4320.msg100440#msg100440

If you're having problems, I can help put one together for you with https://www.falstad.com/circuit/


Observations to note:
* Compare 1/4 wave resonant frequencies
* Measure and understand the geometric ratio between resonant frequency in transverse and longitudinal modes.
* Measure Q factor in both circuits.
* Observe differences in voltage magnification.
* Determine effective velocity of both circuits using 1/4 wave frequency.

[F6FLT]

Performing experiments yourself, or speaking from third-hand knowledge again?
...

I did not wait for you to do experiments on longitudinal waves, even with plasmas according to the method of R Zimmerman. And of course I was confronted with radio radiation.
The difference is that I did not shout "victory, I have a longitudinal wave, I am the worthy successor of Tesla" like K Meyl and others, because I would have a link between LC circuits, which is conventional and within the reach of everyone.

Observations to note:
* Compare 1/4 wave resonant frequencies
* Measure and understand the geometric ratio between resonant frequency in transverse and longitudinal modes.
* Measure Q factor in both circuits.
* Observe differences in voltage magnification.
* Determine effective velocity of both circuits using 1/4 wave frequency.

The method is incorrect. As already said, various resonances or Q factors do not prove a longitudinal wave, but several tuning modes. This is common in electronics  (I even invented a double oscillator with a single triode, which oscillates on two frequencies).

As for speed measurement, in the near field it is impossible because of standing waves and a too slow front. Metrology is a science in itself.

If I stopped testing in this field, it is because I see the experimental complexity, especially to eliminate the EM wave. It is not the naive methods used so far that prove anything, they are inadequate.
I have proposed two very simple methods which remove all doubt, but the bad methods are obviously preferred, they allow to keep one's illusions.

So establish your UK/US link and show that it is not a radio wave. You said you were working with Eric Dollard on this, what's the status? Only then can we start to talk about the possibility of a longitudinal wave in free space or through the earth.

[Hakasays]

The difference is that I did not shout "victory, I have a longitudinal wave, I am the worthy successor of Tesla" like K Meyl and others

You can shout victory if you wish.  I can explain circuit configurations with anomalous effects that I have only seen replicated online by a few other people.
I've not see any naysayers willing to perform actual experiments.

The method is incorrect. As already said, various resonances or Q factors do not prove a longitudinal wave, but several tuning modes. This is common in electronics.

As I've stated multiple times, transverse and longitudinal modes are always present in every system.  Building transverse+longitudinal network analogues merely highlight the differences between them more directly.  Makes them easier to explore.
It's important to understand operating principles because they help guide our experiments.

As for speed measurement, in the near field it is impossible because of standing waves and a too slow front. Metrology is a science in itself.

It seems you still do not understand the rationale behind building transmission network models on the bench.
The components represent lumped elements in an arbitrarily long transmission line.

For example, each element in the transverse/longitudinal network could represent a 500ft section of transmission line across telephone poles.

So establish your UK/US link and show that it is not a radio wave. You said you were working with Eric Dollard on this, what's the status?

I've been posting regular updates in the other thread.  I also posted links in that thread to others with more detailed experimental setups you've probably still haven't explored.

If I stopped testing in this field, it is because I see the experimental complexity, especially to eliminate the EM wave.

I can tell.  Your demeanor is of someone who has stopped exploring.

[F6FLT]

You can shout victory if you wish.

I can't. Some people have built a lifter and shout "victory, I have antigravity". Ridiculous.

As an experimenter since I was very young, I can only claim victory if it works without artifacts, according to the claimed principle.

Sorry to be an experimenter, not a reproducer of other people's experiments, which even if they work, can't be proof of what they say about it.

I can tell.  Your demeanor is of someone who has stopped exploring.

Attacking the person when you don't know how to invalidate what he says, is a well known sophism.

You can't tell anything. You don't know anything about me. I am mostly experimenting with radio, and unlike you who has not yet established your US/UK link by longitudinal waves, I have results like this omni-directional UWB antenna I invented last year, which has been on my roof for a year, and outperforms all commercial antennas of its class and volume like discone antennas.
I know what I'm talking about when it comes to electromagnetic waves, that's my domain. I see effects falsely claimed as evidence of longitudinal waves by people who obviously have no experience with them (or are lying to us).

The thing is F6 what your saying here also applies to you and every thing you say, at the end of the day F6 your just a critic who likes rubbing up people the wrong way I think the term is a Troll and iut applies to you.

[Hakasays]

Attacking the person when you don't know how to invalidate what he says, is a well known sophism.

F6, your hasty responses suggested to me that you hadn't explored any of the source material and references that you asked me for.
(specifically Adrian Marsh, since he maintains very high quality work that is directly related to tellurics as well as transverse v. longitudinal propagation)

It felt like you were trolling me by asking for material you weren't going to read.  I apologize if I was mistaken.

[Allcanadian]

Hakasays

As I've stated multiple times, transverse and longitudinal modes are always present in every system.  Building transverse+longitudinal network analogues merely highlight the differences between them more directly.  Makes them easier to explore.
It's important to understand operating principles because they help guide our experiments.

I would agree longitudinal waves are different from transverse waves like RF.

In fact I built a neat little detector circuit made of an air coil, rectifiers and two LED's inside a copper mesh cube aka (Faraday Cage) to help determine the difference. As is often the case I stumbled onto the radiant/longitudinal wave circuit/effect which penetrated a metal enclosure by blind luck. From there, as you implied, it was just a matter of determining what was happening and why by working the problem/logic backwards. That is, how does a Faraday Cage actually block EM waves?, how could a different wave property circumvent said blocking effect?. 

So all this nonsense F6FLT is talking about seems foreign to me because I nailed down most of this stuff almost a decade ago. I mean, if some thing is doing something different then there must be a rational explanation. We can apply as many beliefs, dogma's, bandwagon fallacies, denial and other excuses as we want but at the end of the day if there's something to it then it should be addressed.

Here's how it works and it's actually so simple anyone can understand it...

The actual problem is that most are generalizing and confusing the terms "frequency" and "period". Frequency relates to the cycles/changes per second while the time period relates only to the rise/fall time. Ergo we can have a low frequency(cycles per second) and a small period(rise/fall time) which displays the same effects as a high frequency. Can you see the problem?, the effect has little if nothing to do with "frequency" only the rise/fall time normally associated with said frequency. It's actually the rise/fall magnitude which determines the nature of the external effects not frequency.

It's a question of extremes. What do you think would happen if we could discharge tens of millions of volts in nanoseconds?. It's not the voltage that matters it's the total energy which could be transformed which always relates to the time period...

So the longitudinal wave/Faraday Cage penetration problem has nothing to do with EM waves or frequency. It only relies upon a term few even talk about but Tesla did which is the time period. So the new rule is that if the total rate of change (magnitude of event within the smallest time period) occurs and said change occurs faster than the rate of conduction then said disturbance can penetrate any conductor and a Faraday Cage.

So it does come back full circle to understanding the principal of the thing in question as you implied. In my mind there is nothing more important than the principal which defines the how, where and why of something. Not some rigid dogma some other person imagined but something we can prove for ourselves. In this respect F6FLT is correct however his mistake is in thinking his or others experience/knowledge must be similar to ours/others but this is not always the case. What if we observed/measured something almost nobody else has, a discovery?. As they say... new discoveries are made every hour of every day somewhere.

Regards
AC

[Hakasays]

In fact I built a neat little detector circuit made of an air coil, rectifiers and two LED's inside a copper mesh cube aka (Faraday Cage) to help determine the difference. As is often the case I stumbled onto the radiant/longitudinal wave circuit/effect which penetrated a metal enclosure by blind luck. From there, as you implied, it was just a matter of determining what was happening and why by working the problem/logic backwards. That is, how does a Faraday Cage actually block EM waves?, how could a different wave property circumvent said blocking effect?. 

IMO the Faraday cage can do a good job of blocking electro-magnetic radiation (down to a reasonable level), but for impulses/disruptive discharges, or longitudinal tuning the Faraday cage just becomes one plate of a capacitor.

It's not magic per-se, but it is a very different property than we're normally used to (modern electronics are usually designed to prevent longitudinal transients.)

The actual problem is that most are generalizing and confusing the terms "frequency" and "period". Frequency relates to the cycles/changes per second while the time period relates only to the rise/fall time.

Indeed, for impulses+transients, terms like 'frequency' lose meaning.  Transients generally result in exponential curves which have to be measured in things like decibals-per-second.

So it does come back full circle to understanding the principal of the thing in question as you implied. In my mind there is nothing more important than the principal which defines the how, where and why of something. Not some rigid dogma some other person imagined but something we can prove for ourselves. In this respect F6FLT is correct however his mistake is in thinking his or others experience/knowledge must be similar to ours/others but this is not always the case. What if we observed/measured something almost nobody else has, a discovery?. As they say... new discoveries are made every hour of every day somewhere.

I would say that if there is room for BIG discovery, it would be in places that are poorly mapped+explored today.

Post-1890's Tesla was focused almost exclusively on high-voltage impulses and disruptive discharges.  In the modern world, longitudinal impulses/transients are usually suppressed instinctively in order to protect solid-state electronics.

[F6FLT]

Hakasays
I would agree longitudinal waves are different from transverse waves like RF.
...

Everyone agrees with that, including me, it's a cliché.

AC and Hackasays don't seem to understand that the question is only to demonstrate the existence of this wave in free space, or through dielectrics or conductors like the earth.

On the other hand, they do not know how to define mathematically this wave, how much energy it carries, what level would be emitted by a Tesla coil, what level would be received after a path of such or such nature.

The "science" of those who refer to Tesla to speak about longitudinal wave is of the zero level, which does not prevent them from telling us that it would be like this or like that, without obviously providing the slightest experimental demonstration nor the slightest equation nor quantified data.

As far as the longitudinal wave is concerned, there are much better formalizations than the rumor coming from the mythology around Tesla, like the one of A Zhakatayev ("Long-Range Longitudinal Electric Wave in Vacuum"), or of B Zohuri ("Principle of Scalar Electrodynamics Phenomena Proof") and many others, while the transmission of a Tesla coil is perfectly described by conventional electromagnetism, as by Z Blazevic ("Simple Transmission Line Representation of Tesla Coil").

But on these subjects it is necessary to think rather than to indulge in a myth, an activity where one rarely meets FE "researchers".

[Hakasays]

F6, was I correct in assuming that you haven't yet explored the experiments and reference materials you asked me for?

[F6FLT]

F6, was I correct in assuming that you haven't yet explored the experiments and reference materials you asked me for?

I have experimented with Tesla coil couplings. It is all conventional, I have not found any anomalies, nor do I see any in past experiments by others. They confuse the effects either with near field coupling for short distance links or with electromagnetic waves for long distance links.

So I am waiting for convincing results from other experimenters, which is why I was interested in your US/UK transmission, which might well demonstrate this if it succeeds.

I asked you how you would eliminate the likely artifact of an electromagnetic wave, since this is the huge weakness of long distance experiments with Tesla coils, and I don't see any commitment on this point.

I asked you where you were with your project: no answer.

Instead I see the usual rhetoric about theories that are unfounded because they are not proven by experiment, often off topic (e.g. the question of transmission lines), those created by this mythology around Tesla. I am not part of this bigotry, sorry.

If you say you are experimenting, please really do it, tell us where you are at, and provide your concrete results, even if they are negative because we learn from them too.

As far as I'm concerned, and until I get proof of the contrary from those who believe in it, there are no longitudinal waves produced by Tesla's coils. And the little that could be produced indirectly would anyway be completely masked by the EM waves generated by the current in the coil, a coil that is a classical radio antenna and that Tesla's experimenters do not even bother to screen!

I do not deny the possibility of the existence of a longitudinal wave in free space or others, but it will be complex to implement, the level attenuating in 1/r² and not 1/r like an EM wave.
I have already provided links to a much better formalization of the longitudinal wave theory, such as that of Zaimidoroga recently mentioned by Grumpy, who also proposed with Podgainy an extension of Maxwell's equations to include the longitudinal wave ("Nonrelativistic theory of electroscalar field"). There are others, like B Zohuri who arrives at results similar to Zaimidoroga, or Zhakatayev. As for the experiments, there are many of them, in particular linked to the scalar wave itself  linked to the potential vector, some of which I have tested, such as that of Zimmerman with plasmas. It is also confronted with the possible pollution by an electromagnetic wave (my duplication of this experiment was inconclusive because of that) but also because the experiment, as for Tesla's coils, can be explained classically (see the conclusion of the reproduction that KJ6VW made).
One must understand that the existence of a longitudinal wave imposes the loss of gauge invariance, which seriously challenges a solid part of physics. The potentials would no longer be relative but absolute.
So before tinkering, we must put everything in perspective to understand what we are dealing with, to avoid doing anything and drawing conclusions that are as false as they are hasty on what we observe in the experiments.

[Hakasays]

I have experimented with Tesla coil couplings. It is all conventional, I have not found any anomalies, nor do I see any in past experiments by others. They confuse the effects either with near field coupling for short distance links or with electromagnetic waves for long distance links.

I understand you have a great deal of experience working in the EE field, but please don't ask me again for information if you don't plan on pursuing.  It wastes both our time.

I asked you how you would eliminate the likely artifact of an electromagnetic wave, since this is the huge weakness of long distance experiments with Tesla coils, and I don't see any commitment on this point.

I asked you where you were with your project: no answer.

The intended strategies to quantify both modes were addressed the first time you asked me:
https://www.overunityresearch.com/index.php?topic=4320.msg99802#msg99802

Adrian has his own method that somewhat overlaps with this that you can also critique: https://www.am-innovations.com/telluric-transference-of-electric-power-brookmans-park-am-radio-transmitter/

If you say you are experimenting, please really do it, tell us where you are at, and provide your concrete results, even if they are negative because we learn from them too.

I've been posting updates regularly in the other thread; my current issue is maximizing dielectric coupling to ground through a high surface-area, as my earlier hypothesis that achieving a low resistance ground by hitting the water table would be good enough did not pan out experimentally (at least in the 160m band).

Adrian's further ahead of us in terms of direct experimental results, which you are always welcome to comment on:
Mid-field:  https://www.am-innovations.com/transference-of-electric-power-single-wire-vs-telluric/
2-8 miles: https://www.am-innovations.com/telluric-transference-of-electric-power-mf-band-2-8-miles/
27-70 miles: https://www.am-innovations.com/telluric-transference-of-electric-power-mf-band-27-70-miles/
110 miles: https://www.am-innovations.com/telluric-transference-of-electric-power-mf-band-110-miles/


The reason I've been focused on Transverse vs. longitudinal transmission line analogues lately is because it provides a potential operating principle that can be directly predicted and modeled without writing any new laws of electricity.
These networks can be used as analogues to represent systems of arbitrary size.

That's why one near-term goal is determining the bulk impedance properties of freshwater, saltwater, and various quality soil; because one could directly predict and engineer telluric transverse and LMD mode performance knowing only the volume inductance/resistance/capacitance/conductance at a given frequency.
It would also tell us if we need to scrap the 160m band experiments and go down to the 50-100kc region where Tesla was operating.

That's why I was asking about dielectric loss-tangents in the LF/MF bands.

[F6FLT]

...
That's why I was asking about dielectric loss-tangents in the LF/MF bands.

This question does not make sense, it depends on the terrain crossed, and near the surface even the weather. In the Sahara desert or along the Scottish loch, it is totally different.
If you don't know where your longitudinal wave will pass, answering this question for all cases will give a huge range of orders of magnitude depending on the location, the depth, even often unknown especially when the path is deep in the ground, and the answer will be of no use.
Do you know the path that your longitudinal wave will take? Does it stay near the surface? Does it cut the terrestrial arc?...

[Classic]

Can anyone explain me in simple terms what is light ? How about Dark ? What is dark, absence of light or opposite of light ?

[AlienGrey]

white light doesn't come from the sun it's dark out in space, everything is about free electrons hit by the sun's rays
if you hit the right frequency of the color it will cause the electrons to vibrate and deplete and while doing that
they give of light if you hit it's frequency, a bit like the depletion layer in a diode but the p and the n layers are
together so you wont se it glow unless it's an LED construction.