Can electricity flow through air w/out sparking?

I might vote for avalanche breakdown. Also, the current voltage curve for discharges is quite non linear and exhibits negative resistance in the spark region.

Later...

Ron Capik

Broadcast radio and TV do actually matter. But they're not electricity flowing through the air. An electrical current is a bulk flow of charge. Radio and TV is broadcast by massless and uncharged electromagnetic radiation.

On Fri, 18 Aug 2006 14:15:02 GMT, in message , "Michael A. Terrell" scribed:

Well, thanks for the info.

On Fri, 18 Aug 2006 20:54:25 -0500, in message , Greg Hansen scribed:

Well, since the transmission and reception of electromagnetic radiation depends upon the presence of an electric field, how do you justify that electromagnetic radiation is not a form of electricity? Since electromagnetic generators produce most of the electricity that is used in industry and residences, I am again wondering how electromagnetism is distinctly separate from electricity?

Read up Faraday FFS.

Graahm

Can electricity flow through air w/out sparking?

Yes!

We need to be much more sensitive to the process of how electons or photons move through air. Humans are not developed this way.

Change one word in your question -- change air to water--- Sharks and other aquatic life are able to sense living organisms by their electric field.

I don't know of any "air" examples. But suppose you take a TV picture tube. We know that electricty is passing from the gun to the screen. Suppose we let just a little air into the tube; I doubt it would spark. Suppose we compress 1,000lbs of air in the tube, I suspect it will burn up the gun in a instent. Suppose we use an inert gas; neon, for example, it would probably light it up like a torch. Define air!!

I say yes, but humans are not capable of detecting electricity flowing though the air in such small potentials. I have often suspected ants can do this and possibly moths but I just don't know. How do cattle all stampede in an instant? how do birds in a flock all turn at the same time?

A wireless, diaphramless speaker would be an interesting development.

Bless you Radium; you are a thinker. A few on this list are inventors and will try to develope your ideas into practical applications. But Radium, beware the politicians, they got Socrates killed.

Pj

No.

Funny thing, though - humans have developed instruments which are much, MUCH more sensitive than anything in nature.

But electric fields are not electrons, nor are they the "flow of electricity." So this is utterly irrelevant.

What do you think a "little" air is? Quantify your statement! Are you at all familiar with how much air (actually, how little) is necessary to make an ordinary vacuum tube (let alone a CRT) behave as a "gassy" tube? Do you know what the symptoms of a "gassy" tube are?

Air: 78% nitrogen, slightly under 21% oxygen, slightly under 1% argon, trace amounts of CO2 and a slew of other gases; that'll do for a definition for these purposes. But that's irrelevant, too - anyone who thinks a CRT will function with an "inert gas" in it has apparently never been exposed to that wonder of modern technology, the neon lamp. (Yet Another Hint: "chemically inert" doesn't have a whole lot to do with how the gas in question behaves in the presence of an hefty electric field....)

So would anti-gravity boots and an responsible government, but I'm not holding my breath on either and I'm certainly not expecting the sort of idiocy we've come to expect from Radium to get us one micron closer to ANY "interesting development."

If you consider Radium to be a "thinker," all I conclude is that your exposure to that species has been exceptionally limited.

How do you justify calling the plastic wrapping around a wire an insulator when the electric field goes right through it?

Electromagnetic radiation is a gauge field, an electric current is a flow of particles that have charge. Charges interact with the fields, but that doesn't mean the field is a flow of charge. A "D" cell has a dipole field looping from the positive terminal to the negative, but that doesn't discharge the battery.

You could wave your hands and say "electricity" to encompass all related phenomena, if you like. But when someone asks whether electricity can flow through the air, they're clearly not asking whether light can flow through the air. Light and charged particles are different things that behave in different ways. You can bend a beam of electrons with a magnet, for instance, but you can't bend a beam of light. And microwave circuits are very different from electrical circuits.

Exactly, so electricity and electromagnetic radiation are two seperate entities. As I thought. No offense to Alan.

What do you think an insulator is ?

Graham

You're *BOTH* stupid.

Stupid is as stupid does I guess.

Graham

On Sun, 20 Aug 2006 05:47:15 +0100, in message , Eeyore scribed:

So far, so fascinating. My first impression is that a Faraday rotator works in much the same manner as a microwave circulator. But then, my first impression of my ex wife was of a wonderful, charming woman.

Oh by the way, I now realize that I was overly broad in my description of electromagnetic radiation requiring the presence of an electric field, as I was ignoring optics. Optics is getting away from electricity just a bit, but electrical circuits are still required for getting the information in and out of the fiber.

On Sun, 20 Aug 2006 09:19:22 -0500, in message , Greg Hansen scribed:

Well, the preparation for broadcast relies quite a bit on a real mass of real charged particles. That "massless and uncharged" radiation requires quite a bit of electrical oomph behind its transport into free space. Now here's a question: if radio reception is dependent on an electric field intensity of some minimum value, and an electric field is defined as existing in any space in which a force is exerted on a stationary charge[1], how does it follow that electromagnetic radiation is uncharged? If the field strength at my receiver is 50uV, where did that V come from? Is voltage also not electricity?

An insulator, in varying degrees, will block an electric current. Insulators can also stop electromagnetic radiation, it's just that the insulators take a different form. Lead, for instance, is an insulator against gamma radiation.

I see that you wish to describe the term "electricity" to mean only "flow of charge." Why are you being so selective? Why is "electric field" excluded? Indeed, why exclude fiber optic communication? The underlying principles are the same.

"An electric field is said to exist in any space in which a force is exerted on a stationary test charge." Would you agree or disagree that it follows that there must be an electric field surrounding any charged body? You argue that a flow of charge is electricity, but you deny that the resultant electric field is electricity, when in fact the two are inseparable.

I don't have to wave my hands, all I have to do is consult a textbook. Electromagnetic radiation is taught and described in countless texts, and all of them, in one way or another, describe or title themselves as teaching electricity. Why would an inductor, which relies on electromagnetism every bit as much as an FM radio, be classified separately from electric circuits? Indeed, I think you would be hard-pressed to find a text that suggests that the realm of electricity is being left behind when descriptions of radio and television begin.

Furthermore: from what discipline come technicians who work on both wired and wireless communication? Electronics, and the field is not divided into three parts; copper wire, wireless transmission, and fiber optic. The same electronics technicians and engineers work all three fields. Do not journeyman electricians understand electromagnetic radiation? They are not confined to working only on DC copper lines.

You can certainly bend a beam of light, using prisms, optic fiber, or simply a glass of water. Different tools for different jobs, but again, the fundamentals are the same. You can't measure microwaves with a light meter, but they are both (as you argue) forms of electromagnetic radiation. If the tools used define the discipline, then the discipline of Electrical Engineering would have split off into a half-dozen professions ages ago.

Well, if microwave circuits are not electrical circuits, what are they? Cheese? Do I then hire a dairy farmer instead of an electronics technician to work on my microwave radios?

References consulted: Basic Electric Circuits, Donald P. Leach Electric Circuit Analysis, Taber/Silgalis Communications Electronic Circuits, J.J.DeFrance

On 20 Aug 2006 12:44:33 -0700, in message , "Radium" scribed:

No offense taken, as you are agreeing with an improper premise. So it seems that your goal in posting is to find someone who will agree with you regardless of the viability of the proposition. Am I correct?

Wrong.

In this case you experienced the change of type of energy from electromagnetic radiation (photons, which lack charge) to electrical energy.

The differences get rather large! Shields against electromagnetic radiation to some major extent are electrical conductors!

Do any electrons or any other charged particles or charged particle clusters flow through the fiber from one end of the fiber to the other?

No electrical energy is expended if the electric field does not move any charged particles.

An inductor relies on reversable transformation between electrical energy and magnetic energy, which are both distinguishable from each other as forms of energy, and both of which are distinguishable from electromagnetic radiation which is a distinguishable different form of energy from electrical energy and magnetic energy.

Although most electronics and AC circuit analysis texts that say much about radio communications involve changing of energy type between "electromagnetic radiation" (photons) and "electrical energy" (volts times coulombs). That is often done with a bidirectional transducer that is often called an "antenna", although there are unidirectional and semiunidirectional transducers such as LEDs, solar cells, magnetrons and klystrons, masers and lasers, and lightbulbs.

Aren't there more than that many job classifications dealing with electricity, light, and forms of electromagnetic radiation other than light NOW?

To clarify somewhat - microwave circuits are a specialized subset of electrical circuits that have requirements of design and layout specific to handling of AC at frequencies that high.

I would advise basics-learners to grab a copy of any edition of "University Physics" by Sears, Zemansky and Young! That one derives existence of electromagnetic radiation, even to extent of deriving "speed of light in vacuum" ("C") as a function of permeability and dielectric constant of a vacuum! For that matter, derives speed of electromagnetic radiation in insulating materials of any permeability and dielectric constant! (That would be C divided by square root of product of permeability and dielectric constant.) Index of refraction of any transparent material with unity permeability is the square root of the dielectric constant, at the frequency in question! (Dielectric "constant" can and often to usually does vary with frequency.)

- Don Klipstein (Jr) ( snipped-for-privacy@misty.com)

A very high resistance.

And a significant amount of work is done by mechanical pumps to get water from the treatment plant to your home. Do we now equate water with a spinning rotor? Or with the electricity used to turn the rotor, or the heat that was used to generate the electricity?

Energy is converted from one form to another.

Uh... seriously? Charges are a source of electromagnetic field. If the electromagnetic field were charged it would be self-interacting. That would mean, among other things, that Coulomb's law would not be correct, and it would mean the breakdown of the superposition principle.

Voltage is electric potential. It means an electrical current could be produced if there were charges in the region that were free to move.

Different form with different physics, because they're different entities. An insulator stops an electrical current because it doesn't have anything in conduction bands. Something that will stop radiation is not called an insulator, it's called shielding. Radio waves are stopped by conductors when they induce electrical currents in the shielding that destructively interfere with the incident radiation.

Because they're different entities with different properties, and there are different ways to work with them, and so it's useful to distinguish one from the other.

Funny you should mention that. I was involved in an experiment that used a fiber optic line to get information out of a detector that was held at about -2000 volts with respect to ground. A fiber optic line was used precisely because it does not conduct electricity. It carried light quite easily, though. It needed electronics on one end and the other to convert electrical energy to light energy, and back.

Do you think they apply Ohm's law to electromagnetic radiation? Put a multimeter on a fiber optic cable? Electronics technicians also cut metal, but we wouldn't say they sweep up bits of electricity when they're finished. They do whatever the job requires, but that doesn't mean it's all the same physics.

No, the fundamentals are not the same. A beam of electrons bends in a magnetic field in accordance with Lorentz's force law, exerting a force proportional to all three of charge, velocity, and magnetic field. Light bends in a prism because of induced moments that create secondary radiation which interfere with the incident light in accordance with the superposition principle.

You can also bend the path of a golf ball by rolling it on an uneven green. But it takes more than bending to claim that the physics are fundamentally the same.

I wasn't thinking of microwave frequency circuits, but rather circuits of microwave radiation. They involve waveguides whose geometries determine their effects. At a design level it's closer to acoustical circuits (like a trumpet) than to electrical circuits.

Try one on electrodynamics or optics.

So what's that got to do with electric fields ?

Graham