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

--- Quote from: penfold on April 08, 2022, 07:47:46 am ---"Do" is the present tense, the content of those videos is more about the early days, and the nature of electrical supply and consumption has changed somewhat since then. Anything to suggest that it is still the optimum solution?

--- End quote ---

That's not what she said.

The content of those videos is about how important Steinmetz work is, exactly because it's still relevant to this very day.

Get rid of your bias so you can see things clearer.
adx:
My view on those videos is it seems a bit fangrrlish and "story" rather than dry sequence of facts - which is totally appropriate for a YT video, but quoting it as evidence is similar to someone quoting a movie as evidence because it was well received and based on real events.

"how important Steinmetz work is" <> "complex numbers ... The ubiquitous and affordable distribution of energy wouldn't be possible without the help of its application to engineering."

Sounds utterly ridiculous to me, synthetic, when the link is distant: His total work is much more than complex notation, this seems to have been motivated more as a non-mathematical hack (optimisation), and both he and Clarke seem not to have given two hoots (for the most part) about the mathematical basis of complex numbers and solutions when using this notation. Rather like HP's VNA - sqrt(-1) need not exist, because it is optional (I would like to suggest irrelevant) to the meaning of j. And then there is the whole assumption that that notation was required to make energy affordable. And the unavoidable inference that it includes petroleum, solar etc. Claims made from a position of sensationalist hyperbole don't work, because they are illogical. They just sound like they do. The sentiment I might agree with quite happily, but it is not a statement of historical fact.

Anyway, I was meant to be replying to some other stuff first.
snarkysparky:
Does anybody really think complex numbers don't enter daily use in electrical engineering ?

The banner ad running at the top of this page for me says

"A single sweep of impedance phase"   Zurich instruments.

phase is the imaginary part.
adx:

--- Quote from: snarkysparky on April 08, 2022, 12:22:06 pm ---Does anybody really think complex numbers don't enter daily use in electrical engineering ?

--- End quote ---

Of course. Well, depends on how you define complex numbers in your mind, but if I wind the cursor along on my "cheap ass VNA" (earlier in thread) hang on Thorlabs oh crap boxes everywhere I thought it was sitting on a great big diplexer I had been meaning to measure one of these years. Looks like they report results in R + C or R + L depending, that was not to be my point, hang on again no it was but not so directly. If I see a "j" number I think about L or C or equivalent delay structure, I think phase shifted component, I think integral or differential of source sinusoidal voltage. That's all (that, and latent unease over the uncertain meaning of j).

Some people prefer to think in terms of complex numbers, imaginary (rotated) numbers, mathematical concepts they were taught as young tykes, or even some greater cosmic form. All power to them - that's their way of thinking. I've been interested in that cosmic form in this thread, and I have also learned that the link to daily electrical engineering is so loose as to not be worth worrying about. My best idea is it is a fiction that arises from transforms used to come up with differential calculus solutions.
adx:
Catching up a bit with partly prepared reply pieces:


--- Quote from: TimFox on March 24, 2022, 03:55:43 pm ---...
Or, one could do an .AC analysis in SPICE (which is strictly algebraic and undoubtedly uses complex algebra internally).
...

--- End quote ---

It does:
https://www.emcs.org/acstrial/newsletters/summer09/HowSpiceWorks.pdf
A good description I found after all these years.

I guess most (all?) fundamental linear circuit elements 'are' either real or imaginary, kind of even more sparse than a complex model.

Or you can do a .TRAN, and bypass all the frequency-based transforms. If you can't see poles and zeroes in "mathematical" form, then there's not a lot of point. (That is sort of the point of my 16th century mathematics / raw arithmetic jibe.)

Edit: yes I know it's a pain to get a frequency response graph out and set up a sweep. In hindsight I use .ac more than I thought. But a lot of the time I want to see what I'd see on a scope.


--- Quote from: TimFox on March 31, 2022, 04:32:38 pm ---Yes, the voltages indicated as I and Q on a two-phase lock-in amplifier are "real values" in the common mathematical sense of the word.
However, when I use these values to calculate something useful, such as the frequency response of an amplifier or an impedance as a function of frequency, being of sound mind I do the simple complex algebra in Excel, setting the imaginary part of the voltage to "Q" and the real part of the voltage to "I".  Both values are functions of frequency going into the algebraic calculations.

--- End quote ---

That's fine. But you can do the same with reals (no complex analysis toolpak). My point is that going to a new 'domain' of numbers isn't a requirement, when [deleted waffle].
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