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

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adx:

--- Quote from: EEVblog on January 13, 2022, 06:41:14 am ---I've been gone for several weeks, can someone TLDR me what happened here in regards to the quantum field theory explanation? Thanks.

--- End quote ---

Not sure, but I think it's done at least one more cycle of spiralling in on zero or more answers!

Best I can see is it's down to semantic differences, which trigger different thought pathways in people's heads leading them to have no way to reasonably dispute what they are now thinking, or at least wondering about the conflict now centred in their minds rather than projected externally. I say, faux psychoanalytically.

I'm starting to wonder if classical theory is grossly misleading through no fault of its own, just that it has propagated through textbooks where the authors have struggled for teachable meaning, now just layers of history and interpretation. Should have prefaced that with an extreme cynicism warning, but seems too true.

Kalvin:

--- Quote from: EEVblog on January 13, 2022, 06:50:55 am ---
<snip>

What if those fields are inside the copper wire at DC?
Again, the fundamental question here is whether energy flows inside or outside the wire (or both). And it should be easiest to argue this for DC.

<snip>

I have never said that Poynting vector math doesn't work at DC, I have in fact said that it does. What I was getting at is that they basically become of no practical relevance at DC.

--- End quote ---

You may find this simulation interesting regarding your questions about fields at DC:


--- Quote from: rfeecs on January 12, 2022, 08:08:37 pm ---Another cool simulation video.  Shows that energy outside the wires flows along parallel to the wire direction from source to load.  Ohmic losses flow in towards the center of the wire.  This one simulates at low frequency, close to DC.


--- End quote ---

snarkysparky:
If that simulation is for DC why does he run it at 1 hz.   Why does he discuss skin depth so much.

Where in the video does he support dc power flowing outside the wires.

If DC power is flowing outside the wires shouldn't it be easy to prove without so much blah blah blah.....

rfeecs:

--- Quote from: snarkysparky on January 13, 2022, 05:04:34 pm ---If that simulation is for DC why does he run it at 1 hz.   Why does he discuss skin depth so much.

Where in the video does he support dc power flowing outside the wires.

If DC power is flowing outside the wires shouldn't it be easy to prove without so much blah blah blah.....

--- End quote ---

The math applies to DC just as much as AC.  It calculates the instantaneous power flow at any point in time.

His simulator is just a fancy calculator, showing the result of E cross H.  The E field in a good conductor is negligible.  So E cross H inside the wire is also negligible.

 ... blah blah blah.   :horse:

adx:

--- Quote from: adx on January 13, 2022, 02:47:50 pm ---...Of course it doesn't - voltage is a property of matter, and is the excess charge density (number of extra or missing electrons from a state of absolute neutrality). When a metal, it represents the mechanical pressure of those electrons in the wire, a pressure that can't exist in a vacuum (unless a cleaner). But the mathematical field can - it predicts the force that would act on a charge if one were there.

--- End quote ---

(About the field in wire thing.) Ok, how about assuming the field isn't real. It is always the interaction between charged particles. If there's only 1 particle in the local vicinity, there is no significant force. Then consider a circuit, with wires, and charges. Are the interactions that drive energy through the system primarily along the length of the wire, or between them?

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