The bifilar pancake coil at its resonant frequency

[web000x]

I'll just leave this here for anyone who cares:


Gyroscopic Primer by Prof Eric Laithwaite


Dave

[MileHigh]

Why, what this analogy explains/predict? BTW Does self-resonating flywheel exist?

It's simply meant to give you insight into a self-resonating coil.  What is resonance?  I can tell you from experience that many people use the term without even knowing what it means.  Resonance is energy cycling back and forth between two complimentary energy storage mechanisms.  In a coil it is the inductance and the self-capacitance when the coil is self-resonating.  In a flywheel it is the moment of inertia and the spring associated with the deformation of the metal when the flywheel is self-resonating.  All flywheels can self-resonate and in real life that is almost always a condition that is to be avoided.

[MileHigh]

Dear MileHigh.

On the contrary, I don't think there was a point to be missed.

Your flywheel ceased to be a " Flywheel " the moment it stopped rotating. IMO your analogy is more akin to a mechanical oscillator.

From my perspective any flywheel that's rotating at a fixed speed ( doesn't matter what speed ) is resonant. My reasoning ? The flywheel, once up to speed requires far less energy than it took to get there.

Kind regards,  Graham.

Sorry, but the analogy was stated specifically to compare a self-resonating coil with a self-resonating flywheel.  A coil is not really fulfilling the function of a coil when no current is passing through it and instead it is simply self-resonating.  Likewise a flywheel is not really fulfilling the function of a flywheel when it is not spinning and instead it is simply self-resonating.  However, both cases deserve to be studied and there is information to be gleamed from understanding them.

The study is much more applicable to mechanical flywheels.  Take the case where a gear is spinning and a clutch engages to effectively knock the gear up to a higher RPM with a strong impulse.  The gear will self-resonate momentarily from the strong impulse that knocks it up to a higher RPM while it is still spinning.  Excessive vibrations from these impulses could reduce the life of the gear from metal fatigue.

Nope, a spinning flywheel is not resonating and doesn't meet the definition of resonance.  Same thing when you have DC current flowing through a coil, there is no resonance.

MileHigh

[MileHigh]

I'll just leave this here for anyone who cares:

Gyroscopic Primer by Prof Eric Laithwaite

Dave

This discussion is not about the angular momentum of a gyroscope and how it responds when you try to change the orientation.  This discussion is about the energy dynamics of a self-resonating coil and the equivalent self-resonating flywheel.  The stuff about the angular momentum is a completely different discussion.

Note again that you don't even have to consider the magnetic field and internal electric field of the self-resonating coil.  The process of vector addition for the magnetic field has been explained multiple times.  The vector addition concepts also apply to the electric field.  For a simple example of a self-resonating coil, or a coil with DC or AC current flowing through it, there is nothing special about the energy stored in the magnetic field.  I can see from what Evostars is reading that there is what appears to be a lots of pseudoscience mysticism associated with coils and the magnetic fields associated with coils.  IMO it's just pulp to capture eyeballs and sell books, downloads, and DVDs and make a living for yourself.

Yes we have evolved from stars. We are stardust, and we all want a nice lush green garden to get back to.

The same people also said this:

You who are on the road
Must have a code that you can live by
And so become yourself
Because the past is just a good-bye.

Teach your children well,
Their father's hell did slowly go by,
And feed them on your dreams
The one they picks, the one you'll know by.

Yes we can all dream.  But we also have a responsibility to teach ourselves and teach others the real truth so that we can go out and make the world a better place.  It's a code of honour and responsibility and respect for ourselves and for others in the world.  In other words, learn and respect the truth and reject the lies and the crap that we have to deal with every day.  You need to amass enough knowledge to be able to discern between the truth and the junk.  It's not easy, but one would hope that you would want to try.

MileHigh

CNN caught lying red-handed:

https://www.youtube.com/watch?v=Ihr7z9P_xaQ

CNN caught in a double-lie:  She says that "(CNN) inadvertently and wrongly characterized."  There was nothing inadvertent about it.  They intentionally edited a clip to completely change the message that someone was saying.  It is absolutely obscene that they did that.  And the only reason they apologized for their lying is because other ordinary people were recording the same event on their cellphones and posted the truth on YouTube.  Take the Red Pill.

[NRamaswami]

Dear Mile High

I requested you to explain your theory and if you have a working circuit I again request you to post it. I have received no response and you have moved to seelf resonating flywheel.

Please I again request you to respond.

Regards

Ramaswami

Sure I would be happy to explain this to you again.  Typically high-frequency voltage travels down the single wire.  However, with no current flow you cannot transfer any AC power into the load.  So the question is how do you get current to flow when there is no apparent current loop in the circuit?  As we know, for current to flow, there must be a loop.

We also know that there exists so-called "stray" (a.k.a. parasitic) capacitance everywhere.  A capacitor is just two conducting plates separated by a distance.  Let's look at a trivial example.  Suppose you are outside in your back yard.  Let's say there is an insulating plastic lawn chair that you are sitting in and your feet are not touching the ground.  We know that the ground is conductive and there is always some moisture in the ground that helps it become more conductive.  We also know the human body is basically salty water, and so the human body is conductive.

Therefore, when you sit on an insulating plastic chair in your back yard with your feet not touching the ground we can say that there is a measurable capacitance between your body and the ground.  It may be very small, perhaps 100 pF, but it is there and it is measurable.  In reality, there is stray or parasitic capacitance everywhere.

It is this stray capacitance that allows AC current to conduct in a current loop that allows for so-called "single wire power transmission."

Here is a typical circuit current loop:

<earth ground> ---> <stray capacitor #1> ---> <high frequency AC signal generator> ---> <load> ---> <stray capacitor #2> ---> <back to earth ground>

When you do a "single wire power transmission" experiment there are typically two "invisible" stray capacitors that allow AC current to flow.  Therefore the load sees both voltage and current and therefore AC power gets transferred into the load.  Small neon lights and LEDs require very little power to light up and that's why you often see them lit in experiments like this.

This is a fairly straightforward concept that should be understood by people interested in experimenting with electronics.