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"Veritasium" (YT) - "The Big Misconception About Electricity" ?

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aetherist:

--- Quote from: adx on February 20, 2022, 02:26:08 am ---You misquote me, emphasis mine:


--- Quote from: aetherist on February 19, 2022, 10:00:28 pm ---...
U mentioned that i reckoned that the discharge of a capacitor must have a very weak additional long term discharge current due to the redistribution of the induced surface charge (electrons) on the positive plate.
And u said that i said that i reckoned that there will be a corresponding very weak additional long term charge current, ie a mirror image of the discharge.
Yes & No.
No i never said that.
And yes, i do believe that there is a mirror image effect during charging.
If the speed of surface electrons is say c/10,000 then their charge/discharge will be very weak compared to the c/1 speed of electons. But i am not sure how far the surface electrons need to move. If they move from the surface of the wire or plate to just under the surface then that distance might be only 1.0 nm. Or they might have to move 1.0 nm along the surface. I don’t think that any electrons have to go all of the way to the battery. Still thinking.

--- End quote ---

You said (in full for context, again emphasis mine):


--- Quote from: aetherist on February 19, 2022, 04:38:42 am ---
--- Quote from: SandyCox on February 18, 2022, 01:02:28 pm ---Can new electricity answer the following question? What is the equation for the voltage across the capacitor, as a function of time, as it discharges through the resistor?
--- End quote ---
I don’t know what the old (electron) electricity equation(s) is for discharge of a capacitor. But the new (electon) electricity equation(s) would be almost identical, except that it would have to show the correct steady half voltage for the correct double the distance, ie for double the time (at least it would for the case of zero reflexions).

And it would need an additional equation for the additional voltage from electons leaving the length of the wire from the capacitor to the resistor. This extra voltage would be for a doubled time, ie electons have to go the wrong way along that wire & later return along that wire, hence a doubled distance & a doubled time. For a giant capacitor & a short or thin wire this voltage might be insignificant.

And it would need an additional equation for the very small extra voltage happening for a very long time due to surface electrons gradually slowly entering the positive plate. But this voltage might be insignificant.

--- End quote ---

I then said (also in full for context, now emphasising):


--- Quote from: adx on February 19, 2022, 08:33:23 am ---From an abandoned post a few days ago: The voltage on a capacitor you might use (ie, a real one you can buy) rises linearly when a constant current (coulombs per second) is injected into it, and falls when that charge is removed. The rate at which the voltage rises is predicted by the capacitance value, it can vary for non-quality capacitors (a well known set of problems) but is generally stable and almost exact for good ones. Not 100% out. There isn't a "charging time" independent of what I just described.

So there is no stair step change in voltage. There is no steady half voltage. There is no distance. There is no double the time. There are no "reflexions". This is all complete nonsense.

There also no polarity effects except electrolytic capacitors which have been formed to a particular polarity - many can be reformed (carefully) and used in reverse. There are no differences between positive and negative beyond the sign.

There is no "very small extra voltage happening for a very long time" in a vacuum capacitor and the small amount that occurs in usual capacitors is due to dielectric absorption, ie the insulator taking a 'set'. That goes away if the insulating material is removed.

--- End quote ---

You'll see I didn't say you reckoned anything. I merely quoted your words to show you how it is totally wrong in the context you used it. Your thoughts are irrelevant to the facts in this instance (where you are wrong). I didn't comment on what you think, only your wrong claims, using some of your exact words for clarity. I took no mental leap of assumption (like I did with your roo-tons, claiming that they were part of a planned deception scheme on your part - is that what you're upset with?).

You introduced the concept of a slow charge effect. We were both talking about a long-term charge retention and discharge mechanism, where the capacitor maintains a small voltage for longer than expected while discharging.

You are now starting to believe I have said things I didn't say. It seems to me you might be both externally and internally grasping at straws to ignore your "rational core". How can I know how you think if I am merely under your skin? To use your own device, I'm not saying I am your rational core, but what if I were?

Of course if you want to define capacitors to be transmission lines in either practical or theoretical effect (or both), then by your new definition then of course you go right ahead and show stair step changes in voltage, distance and that whole first line of nonsense. But I (or is it you?) think you should use the term "capacitor (transmission line)" to avoid ambiguity over your definition.

--- End quote ---
Aha, i see the problem. In red -- when i said surface electrons slowly entering the positive plate, this entering was a part of the overall system discharging, not charging.
The positive plate has positive charge, hence it makes a half of the capacitance. And it loozes all of that when electrons enter onto that plate & eventually snuff out the positive charge.
And i havent given it much thort but charging of the system would have a mirror image process i think.

aetherist:

--- Quote from: adx on February 19, 2022, 03:47:41 pm ---
--- Quote from: aetherist on February 17, 2022, 11:00:30 pm ---<big snip>
--- Quote from: adx on February 17, 2022, 12:48:29 pm ---
--- Quote from: aetherist on February 16, 2022, 09:43:00 pm ---Can any members here use old electricity to explain the traces for the AlphaPhoenix X pt1 & (later) pt2?
--- End quote ---
Once again, this explanation is in this thread way back - the answer is yes. The Maxwell simulation (or even all of them) replicates the features seen in the measurement I think better than expected given the problems with 'X' technique. The only thing I found 'interesting' is the "subtle lift", in both. I didn't quite go to town on the scope screenshot to the degree you have, but I did pore over it for a time not to treat it as some kind of smorgasbord of  Dunning-Krugeresque intrigue but because I use scopes and know what to look for. You are ignoring the fact pointed out in one of my first replies to you that the result of the measurement matches the Maxwellian simulator's output, confirming the theory for that particular case, which is what you question, resulting in the answer "yes" which is a simple word with a stable meaning and unlikely to be confusing unlike this unnecessarily long sentence which you have no problem understanding. Ask your rational core, it asked the question.
--- End quote ---
I am still not happy with lumped element TL models. And i admit that they can replicate the initial 0.2 V that AlphaPhoenix (Brian) got in his white trace for V across his bulb.
--- End quote ---
As I posted in my first reply on page 42, lumped TL models don't replicate the 0.2V, they predict higher, because they are an incomplete subset of conventional theory not intended for antennas. You are right to not like them in this particular application - they are not intended to be accurate for the job.

What does match experiment quite consistently including shape of the pulses, is the collection of field solver simulations based on Maxwell's theory. You ran through them in your second post, and they show conventional electricity theory matching measurement for the white trace.
--- Quote ---But i should have made it clear that i was referring to his green trace for the voltage across the resistor near his positive terminal. <snipperoo>
--- End quote ---
Yes, that is what I meant too. I can see why you have a problem with it now, and needed more detail...

--- Quote from: adx on December 18, 2021, 02:19:09 pm ---If the scope were truly isolated (or ground lifted, depending on where EMC caps go) then the green trace should rise sharply more like the yellow.
--- End quote ---
and
--- Quote from: adx on February 15, 2022, 01:38:27 am ---I explained some of the problems with AlphaPhoenix's result many pages back, one of the main ones which distorts the send waveform I think is common mode coupling. I explained what I think it should look like, if it is measured with a better technique. Others did too, and went into quite some detail.
--- End quote ---
At 7:27 in the video is a diagram of the setup. The probe "reference GND" is the ground clip of the scope. This is tying one side of the pulse generator to Earth, loosely via extension cords and perhaps an inverter from the cars (described in discussions here at the time). The green probe, which is on the other side of the resistor, can thus not see the step directly from the step generator, because it is shorted to ground at the send end (by the ground clip). In essence it can only see voltage due to current getting around the circuit the long way, and a slow change of the GND voltage (which we can't directly see, because there is no probe measuring the voltage between this scope's GND and Earth under the desk).


This is not the way it's meant to be, but surprisingly the experiment still works. It's not necessarily an error if the person doing the test knows that taking this shortcut will still work. Again, I agree the green trace is "wrong", and this does represent the current in that resistor, and hence the current sent into that leg of the 'apparatus'. The other leg should be taking the balance, so it should be seeing nearly all the initial pulse missing from the green side (because that is shorted to ground).

From the clean white trace I can infer that the differential send current is probably fairly rectangular. But subtract the green trace and add the generator step, and that's going to make for a pretty messy voltage on the far side of the unprobed resistor, possibly best not to think about because it is guaranteed to confuse.

The situation would be the same but inverted traces (voltages) if the polarity of the generator is changed - other than that there is no difference and I likely would not test to confirm if I were doing the experiment.

BTW all this isn't so much from theory, as from experience. It just helps explain what is seen. The result is in the white trace, and matches simulation as you already know and I can now see you never really had a problem with. I rarely think about theory when doing engineering stuff, but I sometimes calculate things, and sometimes put it in a circuit simulator if I have really turned my brain inside out. By "Trevor's theorem" I try not to think through tricky situations to arrive at an answer, especially if it is about something that is inverted a number of times - he says you're most likely to get that out by one so would be better off flipping a coin, so save yourself the bother and guess, test, and then swap it round if it's wrong (sort of thing). The important thing is that anyone can be wrong at any time so don't put too much trust in thoughts. Or scopes. In either case trying to bulldoze through a problem with your mind is asking for trouble. It's not about intelligence, but experience in the biz.

Also small apology that I didn't say "subtle lift" originally, or if I did I edited that to "some sort of frequency dependent tilt". This is the white trace before the first reflection arrives. I'm not very interested in why, just noticed it (it appears in the simulations too).
--- End quote ---
Interesting. Here is my opinion re the AlphaPhoenix X pt1. Keeping in mind that i don’t know what a scope smells like. And i am allergic to electrons.  In my opinion Brian has 1 hit & say 7 strikes.
Hit 1. Brian has shown that there is an early significant current in the bulb. White trace (black in my drawing).
Strike 1. Brian fails to show whether the 1/c answer (ie the optional answer (d) ie 3.3 ns) is correct, because his scope can only see down to about 10 ns, & he needs to see down to 1 ns or 0.1 ns if he wants to confirm the 3.3 ns. However Howardlong has confirmed that (d) is correct (his 20 GHz scope can see down to 0.05 ns).
Strike 2. Brian fails to tell us the exact length of his two loops of wires. Hence we can't check to see the (time delay) effect of the heavy enamel on his wires. Oh, & he fails to tell us whether there is enamel on the wires.
Strike 3. Brian's wires etc on his table are all over the place. They should be symmetrical or rectangular or something. And there is lots of hardware in the joints & leads & clips & buckles & bows, but i don’t know whether that pile of krapp can be cleaned up a bit, perhaps he could have used some solder.
Strike 4. Brian's table has more wt of Fe in the frame under the plastic table top (i think it is plastic) than there is Cu wire in his circuit. If u look u will see that there is say 3 mm tween the Fe & the Cu near his bulb, & likewise near his source. In his X pt2 he could show us a trace for a probe on his Fe. Not good. The plastic top might make it worse, it would act as a capacitance multiplier (ie a dielectric).
Strike 5. His source is a 5V DC charger. I would prefer a lead acid battery, like Veritasium had. In fact i reckon that a lead acid battery is essential.
Strike 6. His say 1000 m of Cu is overkill. However i might make this his Hit 2, koz i think the extreme length is going to (accidentally) help me with my explanation for the green trace (which will follow hereunder)(we will see)(a lucky punch perhaps).
Strike 7. Brian failed to show us the trace for the resistor near the switch. This missing trace would for sure help us to explain the green trace (the main topic today).

I noticed the slight rise in the white trace (black in my drawing), but i haven’t thort about it, i doubt that any explanation (& there would be hundreds ovem) would be of much interest. And there are lots of interesting things in the traces. Ok, i have had a think about it (the slight rising grade), i might explain it tomorrow.

Anyhow Hit 1 was a big shock to me. I thort that there might be a brief weak spike, at 3.3 ns, due to radio crosstalk, but instead we see a strong capacitive inductance crosstalk, at 3.3 ns we think. I was shocked (pun alert). However, it lead me to my new (electon) electricity. This feel-good story will someday be folklore. Hell, i might get a Nobel medallion. bsfeechannel might nominate me (& a murmuration of pigs will darken the Sun). But now my genius is needed to explain the Green Trace. Green, my favourite colour – NO, ITS GREY (python joke alert). Ok, i had a think about the green trace, i will explain it in a new reply later today or early tomorrow.

Re any adverse comments that i might have made about TL models for the white trace, i think that these were re the initial part of the transient, ie what i called stage-1 of the transient, ie the part that AlphaPhoenix didn’t & couldn’t measure with his mickey mouse 100 MHz scope. I said that a TL model might be ok for the stage-2 transient, ie AlphaPhoenix's  0.2V bit of the white trace, but that a TL model was almost certainly not ok for the stage-1 transient, but might be with lots of new clever tweeking.

adx:

--- Quote from: aetherist on February 20, 2022, 06:00:44 am ---Hell, i might get a Nobel medallion.

--- End quote ---

That's what thingverse is for.

SandyCox:

--- Quote from: aetherist on February 19, 2022, 10:54:43 pm ---
--- Quote from: SandyCox on February 19, 2022, 02:11:41 pm ---I will attempt to address your misconceptions in the note I am writing.
In the meantime, let me set a challenge: Let's change the termination resistor in Catt's paper from 75 Ohm to 47 Ohm. How, according to "new electricity", will the measured pulses look if we do that?
--- End quote ---
There will be stepped reflexions of current & voltage. I have never worked on that kind of stuff.
But i see that Wakefield already has some traces for 75 Ohm coax with a 40 Ohm termination.
Shown on page 42 & 43 of Forrest Bishop's paper re Reforming Electromagnetic Units…
http://www.naturalphilosophy.org//pdf//abstracts/abstracts_6554.pdf


One thing i can explain, that i think no-one else could explain.
See how the bottom trace jumps up a few V too high, & then falls down to the correct 4V.
That jump is due to the 40 Ohm resistor being saturated with my electons. When the switch is closed electons in that short wire near the switch already heading for the switch will instead of doing their usual u-turn at the open switch they will propagate through the closed switch & onto the core wire of the coax, followed by electons from the resistor. The short wire was saturated with electons too, but the resistor holds a lot more electons per m length than the wire. Hence the brief spike of over-voltage.
U can see the same spike of over-voltage in some of the other traces, but there it is a negative spike of under-voltage i suppose u could call it.

But i have to have a think about what happens to electons inside resistors. Are they annihilated. Do they looz energy. Do they convert to infrared photons.
Anyhow, if there are lots of voids or porous bits or interface surfaces then there must be lots of electons on thems surfaces, & the electons would be doing lots of u-turns.
And they would be jostling lots of surface electrons, which would jostle atoms, & produce heating & resistance & would we know produce a voltage drop.
Its the voltage drop that has me worried. I am glad that SandyCox did not ask me re how exactly do electons produce a voltage drop across a resistor. Still thinking.

--- End quote ---
Your theory is useless unless it can predict values of voltage and current.

aetherist:

--- Quote from: SandyCox on February 20, 2022, 12:34:36 pm ---Your theory is useless unless it can predict values of voltage and current.
--- End quote ---
My electons explain what happens in the various stages of transients.
And if fully developed my theory will give numbers for transients.
Old electricity can't even give good numbers for steady state, eg the half voltage double time for discharge of a capacitor (which my electons explain in the simplest possible way).

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