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Latest comment: 7 years ago by Jimli536 in topic how do inductors really work ?

The article currently says

... air-core (only a coil of wire), iron-core, and ferrite core. Iron and ferrite types are more efficient because they conduct the magnetic field much better than air...

I suppose it depends on what you mean by "efficient". If you're trying to get a high inductance value with the least amount of copper wire (least cost), then yes, air-core will use the most wire (and cost the most), making it the least "efficient". On the other hand, if by "efficient" you mean "high Q factor -- dissipates the least amount as heat", then air-core is the *most* "efficient". Right ?

Maybe there's a different way of saying this without using the ambiguous word "efficient".

-- DavidCary 02:09, 27 Jun 2004 (UTC)

i would think its talking about transformers... - Omegatron 04:57, 27 Jun 2004 (UTC)

I think you're right. Should I move that text to Electronics/Transformers ? -- DavidCary 00:03, 30 Jun 2004 (UTC)

I guess. - Omegatron 18:22, 30 Jun 2004 (UTC)

diagrams

[edit source]

I changed the images from this:

File:Electronics Inductorsseries.PNG

File:Electronics Inductorsparallel.PNG

to this:

so that it is consistent with the other articles. but i am biased, because i made them. so use whichever you want. Sorry I didn't realize the extension was case sensitive. - Omegatron 13:21, 28 Jun 2004 (UTC)

L=B/I? Never come across this before, but it may be true. If B=uH and H=NI then this comes to L=uN. This is something like true but there are usually some other complexities...

how do inductors really work ?

[edit source]

Should this page go into the physics of what happens to electrons inside an inductor ?

I starting writing about why inductors work (for anyone curious about the physics behind them): "Whenever an electron is accelerated...", then I realized I wasn't really sure myself. Even though I'm an EE and I know all about how inductors work. Why do inductors work ? What's going on with the individual electrons ? (Should I stick with a "magnetic fields" explanation, or with a Feynman Q.E.D. "electrons and photons" explanation ?) Is that really appropriate for "electronics" ? Or should we put that sort of detail over at (currently non-existent) http://wikibooks.org/wiki/Modern_Physics:Magnetic_Induction_and_Inductors ?

-- DavidCary 00:01, 30 Jun 2004 (UTC)

what is the electrons and photons explanation? i would just say that the electrons have a net drift velocity that causes a net magnetic field, and when the voltage changes the magnetic field is pushing them in the direction they were already going, so they have a kind of inertia. i guess i don't really have a good way of explaining it either. i guess this comes back to the question about who our target audience is, too. - Omegatron 18:22, 30 Jun 2004 (UTC)

I've read the book Q.E.D. by http://c2.com/cgi/wiki?RichardFeynman WikiPedia:Richard_Feynman . In it, he describes how electrons and photons "really" interact (at least according to [WikiPedia:Quantum_electrodynamics]). In his explanation, there is no such thing as a "magnetic field" or "waves". There are only particles (with "quantum characteristics"). A "electrons and photons" explanation of electrostatics is simple. Off the top of my head: Every charged particle constantly spews out virtual (?) photons equally in all directions. Whenever a photon hits another charged particle of the *same* charge, it is absorbed and the momentum transfer pushes that particle "away" from the first charged particle. Whenever a photon hits another charged particle of the *opposite* charge, it is absorbed and the momentum transfer pulls that particle "towards" the first charged particle. See ? notice there is no electric "field", only particles.

I'd like a similar explanation for the inductor (no magnetic "field", only particles). I suspect it would go something like this: Say we have 2 close parallel wires carrying streams of electrons in the *same* direction. If you could fly close to the wires at the same (average) speed as the electrons, you would see electrons randomly bouncing around with zero average velocity, but the nucleus (including the protons) streaming by. Because of special relativity length contraction, the protons appear to be packed closer together in their direction of travel. Since the protons are packed more densely than the electrons, the electrons in the other wire are *attracted* to the (apparent) net average positive charge. Similarly, when parallel wires carry currents in the *opposite direction ... the wires repel each other." Is that going the right direction, or is it totally wrong ? (EditHint: feel free to *move* this comment to a more appropriate place -- perhaps one of the physics books). -- DavidCary 05:19, 2 Jul 2004 (UTC)

Pretty weird.  :-) Aren't they both equally valid ways of thinking about the same phenomena though? I think it is more appropriate for the physics book, and we should link to it after a basic classical description in our book. The focus is on building circuits, not on the physics involved, but we do have to explain enough physics for them to know what their circuits are doing... - Omegatron 14:41, 2 Jul 2004 (UTC)

Briefly explain. But seriously, it's starting to look less introductory with the barrage of formulae. Jimli536 (discusscontribs) 16:36, 16 October 2016 (UTC)Reply