Idealized grounding arrangement per Merlin!

[Merlinb]

But the textbook definition of electronics is "the study of ELECTRON flow" (hence the ELECTRON in ELECTRONics) whereas the definition of electricity is "the study of charge flow".

Hmm, I'm not sure that's true. I may well be wrong, but I suspect the word electronics existed before the actual negative particle which we now call 'the electron', was proven/discovered in the 1890s (however you want to describe it).

The word electron derives from the Greek elek-tron and literally translates as "the means by which light/sparks are achieved", indeed, the Greeks used the same word for amber, because of its known electric properties.

I don't know much about the very early history of electronics, but it is my suspicion that it was described as "electronics" (simply the means of making light) long before knew what was causing it.

[Russ]

Yes, I was assuming that the pos battery terminal is at a lower potential relative to the string, in which case there would be attraction on that end and repulsion at the other (neg) end, and it seems the two-wave propagation towards the middle would result.

If the string is at the same potential as the pos end of the battery, then there would be no force at that end and it would be like the ball example.

attraction and repulsion are one and the same thing, they're not two different forces in the system, they're the same force with a different referential.

Yes, they just have opposite directions.

I know because my amp is verrrry sensitive to this stuff. lol

Russ

[R.G.]

Here. Let me give each of you some gasoline and a box of matches.

Dr. Ramakumar who taught the fields class back at college, always just smiled at whatever version if this discussion went on in his hearing.

Electrons? Charge carriers? Bah. It's the electromagnetic field that matters.

The speed of actual electrons through a wire, semiconductor, or vacuum is not all that fast. It's a (conceptually now) ball of mass which responds to a first order to Newton's Laws, and to a second law to relativistic effects. The EM field in the conductor moves at the speed of light in that medium (which is not the same as the speed of light in vacuum). The field races through the conductors at at the speed of light in the conductor. For copper PCBs of typical construction, that's about a nanosecond per foot. The electron slog along as the field passes them and cause them to move.

Here's another gallon of gasoline. In a semiconductor, you dope the thing to make it conductive by putting in atoms with either an excess of electrons for the bulk crystal to give a free(ish) electron to get N-type, or atoms with a deficiency of electrons compared to the rest of the crystal to get a P-type.

The absence of an electron is, in the typical poetic jargon of engineers, a hole. A hole is where an electron should be but ain't.

OK so far. Excess electrons obviously move through the crystal by bumping the next atom's electrons out of the way. Electron flow is easy to visualize, little billiard balls moving from one too-full depression to another. And holes, the deviciency of an electron? Easy again. The little electron-holder-cup atoms have one too few, and as an electron fills up the empty space, it leaves an empty space behind it.

Quick - what's the mass of a hole?

Easy, right? It's the same as the mass of an electron because you had to move one electron to fill the hole to create the "hole" flowing in the opposite direction.

As Mencken said, for every complex problem, there is an answer that's simple, direct - and wrong. The measured mass of a hole is different from the mass of an electron, and its drift velocity and other parameters are different. It's one reason that silicon makes better NPNs than PNPs.

[Alex R]

The word electron derives from the Greek elek-tron and literally translates as "the means by which light/sparks are achieved"

Hey, I was getting electronics right all along!

[jmaf]

Here. Let me give each of you some gasoline and a box of matches.

Dr. Ramakumar who taught the fields class back at college, always just smiled at whatever version if this discussion went on in his hearing.

When Merlin said I hadn't given his example enough though, I mentioned college. We had this discussion in 3 or 4 different approaches, nearly 15 years later I still don't know exactly.

There was one particular physics book which around 2/3 along the way, had a Richard Feynman anecdote. It says his dad asked him "Richard, you're a pretty renowned physicist by now, tell me what I asked you xx years ago: WHAT THE HECK IS LIGHT?" He replied "I don't know, why should I know?" And walked away. Something similar was replied by Einstein I think, he said I don't know and if anyone tells you they do, they're lying.

Well I'm detouring from electron-ics here

I have a hunch that we won't be building Merlin's lightbulbway to heaven project so soon. I say they light up minus to positive, in series, not from side to side to the middle. So there's some kerosene floating in the gasoline now.

[Merlinb]

I have a hunch that we won't be building Merlin's lightbulbway to heaven project so soon. I say they light up minus to positive, in series, not from side to side to the middle. So there's some kerosene floating in the gasoline now.

Russ was right, it matters where you put the switch. I was assuming you touched each end of the string to the terminals simultaneously.

If you already have on end connected to -ve, and then touch the other end to +ve, then they will light from the positive end backwards (opposite to the electron flow). Doing things the other way round would produce the opposite (same direction as electrons). I think it still demonstrates that there is no reason to object to conventional current.

[jmaf]

Russ was right, it matters where you put the switch. I was assuming you touched each end of the string to the terminals simultaneously.

If you already have on end connected to -ve, and then touch the other end to +ve, then they will light from the positive end backwards (opposite to the electron flow). Doing things the other way round would produce the opposite (same direction as electrons). I think it still demonstrates that there is no reason to object to conventional current.

I don't think the switch makes any difference. You could split the chain in 200 places, soon as all the links are closed, a circuit is formed and the EMF starts working.

Where the EMF source is does matter, thought, IMHO.

[Merlinb]

I don't think the switch makes any difference. You could split the chain in 200 places, soon as all the links are closed, a circuit is formed and the EMF starts working.
Where the EMF source is does matter, thought, IMHO.

With one end of the string initially connected to the battery there would be an excess of electrons at one of the circuit, a deficit at the other, and a uniform charge-density gradient along the whole thing (I think). Touching the open end of the string to the remaining battery terminal would initiate charge movement at that point first, since it is between those two points that there is initially the greatest potential difference.

Actually, now I think about it, the shunting effect must always propagate out in both directions from whichever point in the circuit is switched...

I still do not follow your argument that all the electrons would start moving simultaneously in all parts of the circuit, during that transient phase.

[Steve Conner]

Electricity flows at the speed of light, but so does light. Therefore the answer depends on where the observer is standing in relation to the circuit.

But in practice the resistance of the filaments would increase the characteristic impedance of the "line" and slow the wave down considerably, so maybe it won't matter that much.

Fourier might have a word to say here. If you energize the circuit with a high frequency (say 100MHz) then the bulbs nearest the source will light brightest, because energy gets lost by radiation, capacitive currents and so on, as you travel further from the source. You can do this with a radio transmitter, Tesla coil or whatever, I've actually tried it.

Now according to Fourier, the switch-on transient, being a step function, can be decomposed into a band of frequencies from "DC to light" as they say. The low frequency components will light all the bulbs evenly, and as we proved with our test above, the high-frequency ones will light the bulbs nearest the source more.

So to me this proves that, when the switch is thrown, the bulbs will light in a wave moving away from the source. Doesn't matter if they're in two strings positive and negative, the wave will spread the same in both conductors.

Saying the same thing in a more practical way: A bulb works the same on AC as DC. Doesn't matter whether you push electrons through it, or pull them through.

[jmaf]

With one end of the string initially connected to the battery there would be an excess of electrons at one of the circuit, a deficit at the other ...

That's what I'm trying to argue since I replied to Russ: I don't think there's any reason for the electrons to leave the battery at all if you connect just one end. So I think there aren't any excess electrons on the light bulbs when, for example, the negative is hooked up and the positive side is switched. I think they're confined in the source of the EMF, namely a battery in this case.

The EMF exists only when you hook up the other end to the battery, then you have the EMF kicking electrons out of the - side and into the + side.

Which is what I tried to argue before: just touching a piece of aluminum on the negative side for example does not create a dead end current into the aluminum, there are no more excess electrons on a piece of metal touching the negative electrode than there were before. No?

So I'm parting from that principle to believe that the EMF happens uniformly after you close the switch anywhere in the circuit, the EMF starts pushing them through(or pulling, etc) and you get a - to + electron flow, or + to - conventional current.... BUT bulbs light up due to electron flow, not charge flow, so they'd light up from - to +. (Assume an "I think" after all these affirmations, I'm really, honestly, not 100% sure of any of this.)

[Merlinb]

just touching a piece of aluminum on the negative side does not create a dead end current into the aluminum,

Hmm, I believe it does momentarily cause a "dead end current". The excess electrons in the battery will try to get as far away from the positive end as they can, which means they must gather at the free end of the piece of aluminium. So yes, the aluminium becomes charged. It becomes nothing more than an extension of the battery, waiting for the circuit to be closed.

[Steve Conner]

Yes, the piece of metal will have a slight capacitance between it and the rest of the universe, which includes the circuit. On touching it to a battery terminal, that capacitance will get charged, which will cause a brief transient current.

[Wilder Amplification]

I have a hunch that we won't be building Merlin's lightbulbway to heaven project so soon. I say they light up minus to positive, in series, not from side to side to the middle. So there's some kerosene floating in the gasoline now.

If you had an airplane on a treadmill....

[mooreamps]

Hmm, I believe it does momentarily cause a "dead end current". The excess electrons in the battery will try to get as far away from the positive end as they can, which means they must gather at the free end of the piece of aluminium. So yes, the aluminium becomes charged. It becomes nothing more than an extension of the battery, waiting for the circuit to be closed.

If you believe this is so, than it would be easy to prove. Right !!!!!!
Not that I personally give a flying flip, but if the piece of aluminum does get charged ; which I am highly doubting because I understand the insides of a battery produces a voltage as a result of a chemical reaction inside the cell ; then one should be able to "untouch" from the negative post, and then "touch" it to the positive post, and then measure a current ?

Ya, Not Happening......

But hey, I'm not calling myself "merlin", so . . . . .. .


-g

[Merlinb]

But hey, I'm not calling myself "merlin", so . . . . .. .

If only my parents had named me Gary, instead