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Veritasium "How Electricity Actually Works"

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rfeecs:
I thought it might be good to start a new thread for Veritasium's new video, the follow up to the "Big Misconception"  video:



He carries out his own experiment, much like AlphaPheonix.

He gives a lot of credit to Ben Watson and other YouTubers including EEVBLOG and Electroboom, etc.

I thought a new thread might be warranted, since the thread on the previous video wandered so off topic into pseudoscience trolling that it is probably being ignored.  :rant:

rfeecs:
One quibble is that several times he says there is an electric field inside the wires but other times he says the electric field inside the wires is zero.

HuronKing:

--- Quote from: rfeecs on April 29, 2022, 04:48:40 pm ---One quibble is that several times he says there is an electric field inside the wires but other times he says the electric field inside the wires is zero.

--- End quote ---

Could you elaborate on this quibble? I thought he was pretty clear when its zero and when its not zero - electrostatic versus electrodynamic conditions.  :)

PS
I thought this was a very nice follow up video - especially in addressing all the specific objections people had to his description of the original thought experiment. What a lot of work to explain how an antenna works.  ;)

PPS
It's still too bad though that Heaviside's work with coaxial cables didn't have time to get mentioned - that's the most immediately practical application of Poynting Theory beyond it being a mere theoretical curiosity.

rfeecs:

--- Quote from: HuronKing on April 29, 2022, 05:34:34 pm ---
--- Quote from: rfeecs on April 29, 2022, 04:48:40 pm ---One quibble is that several times he says there is an electric field inside the wires but other times he says the electric field inside the wires is zero.

--- End quote ---

Could you elaborate on this quibble? I thought he was pretty clear when its zero and when its not zero - electrostatic versus electrodynamic conditions.  :)


--- End quote ---

One point that sounded odd to me is at 8:00 he talks about a python simulation of a DC circuit.  He talks about there is an electric field in the center of the wire.  Maybe I misunderstood what he is trying to say.

At 11:14 he says at the instant that the switch closes, the electric field inside the conductor is no longer zero.  So I guess this would be the electrodynamic condition?  OK, but this condition only exists for attoseconds until the charges move and the field disappears.

We typically assume the boundary conditions for a perfect conductor include: the tangential electric field at the surface is zero, and the electric field inside the conductor is also zero.  This applies both for static and dynamic conditions.  But I suppose this is only an approximation and neglects the attoseconds long period when charges re-arrange themselves.

Then again, in both cases he may be assuming the wire is not a perfect conductor and has some resistance.

snarkysparky:
What pushes the charges inside the wire if there is no electric field inside the wire and the electrons don't push themselves.

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