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

--- Quote from: adx on February 21, 2022, 02:30:38 pm ---[snip]
https://en.wikipedia.org/wiki/Speed_of_gravity
"...between -3×10-15 and +7×10-16 times the speed of light"

--- End quote ---

Wait... what?

I skimmed the page you linked to. It offers an extensive history of the subject and lists quite a few different speeds as predicted by different scientists, but, in the end, the consensus seems to be that speed of gravity = c.

But that's old physics. It includes relativity, etc, but it's still old in the context of this thread. It's exciting to be a part of history in the making.   :-DD
aetherist:

--- Quote from: penfold on February 21, 2022, 03:36:48 pm ---
--- Quote from: aetherist on February 21, 2022, 12:24:24 pm ---
--- Quote from: SandyCox on February 21, 2022, 11:42:52 am ---24mm/80ps = 3e8m/s  :palm:

--- End quote ---
Yes 1000 mm in 3.3 ns is the same as 1 mm in 3.3 ps which is the same as 24 mm in 80 ps.
And the speed of light here is the speed of light in air. The little bit of poly on the pair of wires (ladder antenna cable) would only add say 1 mm at 2c/3, not worth mentioning.
Actually i did measure it to be 85 ps rather than Howard's 79 ps.

--- End quote ---
Do you have any coments on the measurement uncertainty in that number?
--- End quote ---
I dont know how good his 20 GHz scope is. As u can see i got my 85 ps by drawing intersecting lines. It might be all ok to better than 5%, but really u would have to do dozens of tests using different setups & gaps etc etc etc to get a feel for what was doing what.
I would love to get my amateur hands on a 20 GHz scope. I did contact my local university, but no reply yet.
aetherist:

--- Quote from: SandyCox on February 21, 2022, 01:00:12 pm ---
--- Quote from: aetherist on February 21, 2022, 12:24:24 pm ---
--- Quote from: SandyCox on February 21, 2022, 11:42:52 am ---24mm/80ps = 3e8m/s  :palm:
--- End quote ---
Yes 1000 mm in 3.3 ns is the same as 1 mm in 3.3 ps which is the same as 24 mm in 80 ps.
And the speed of light here is the speed of light in air. The little bit of poly on the pair of wires (ladder antenna cable) would only add say 1 mm at 2c/3, not worth mentioning.
Actually i did measure it to be 85 ps rather than Howard's 79 ps.
--- End quote ---
So what's your point? The speed of light = The speed of light?
--- End quote ---
The point is that Veritasium's 1/c is the speed of light through air from his switch to his bulb. But u were still locked into a slightly different problem re the speed of electricity along an insulated wire.
The speed of electricity along an insulated wire does however come into this 1/c problem, but it only comes in a bit later when we get down to looking at the size of the current through the bulb a few ns after the initial wavefront edge of the current hits at 1/c. For example AlphaPhoenix's  0.2 V & its subtle rise (from say 0.2 V to 0.3 V) will have a lot to do with the 2c/3 speed of electricity along the enamel on AlphaPhoenix's wire(s).
penfold:

--- Quote from: aetherist on February 21, 2022, 12:24:24 pm ---[...]
Do you have any coments on the measurement uncertainty in that number?
--- End quote ---
I dont know how good his 20 GHz scope is. As u can see i got my 85 ps by drawing intersecting lines. It might be all ok to better than 5%, but really u would have to do dozens of tests using different setups & gaps etc etc etc to get a feel for what was doing what.
I would love to get my amateur hands on a 20 GHz scope. I did contact my local university, but no reply yet.
[/quote]

And you're confident that there's no classical EM explanation for what's contained in those scope traces?

I was thinking on the lines of what experiments you could do to examine the effects of surface finish on the speed of propagation along a wire. Woud you anticipate any noticeable effects for a copper wire with varying degrees of surface roughness, including nickel plated, tin plated, and kapton insulated? Would any effects be related to any established material properties?
aetherist:

--- Quote from: penfold on February 21, 2022, 11:38:09 pm ---
--- Quote from: aetherist on February 21, 2022, 12:24:24 pm --- Do you have any coments on the measurement uncertainty in that number?
--- End quote ---
I dont know how good his 20 GHz scope is. As u can see i got my 85 ps by drawing intersecting lines. It might be all ok to better than 5%, but really u would have to do dozens of tests using different setups & gaps etc etc etc to get a feel for what was doing what.I would love to get my amateur hands on a 20 GHz scope. I did contact my local university, but no reply yet.
--- End quote ---

--- Quote from: penfold on February 21, 2022, 11:38:09 pm ---And you're confident that there's no classical EM explanation for what's contained in those scope traces?

I was thinking on the lines of what experiments you could do to examine the effects of surface finish on the speed of propagation along a wire. Would you anticipate any noticeable effects for a copper wire with varying degrees of surface roughness, including nickel plated, tin plated, and kapton insulated? Would any effects be related to any established material properties?
--- End quote ---
The old (electron drift inside a wire) electricity can't explain how electricity is so fast along a wire.
And the Poynting Field version can't explain how electricity is slowed by a thin coat of insulation on a wire.

Classical em radiation might answer much of what we see in traces. For example almost every possible theory would say that Veritasium's bulb might feel a signal at 1/c seconds. It would be difficult to come up with a theory that didn’t.
And it appears that lumped element TL models can explain some of what we see in traces.
I think that my new (electon) electricity might explain traces that others can't.

A lot of professors are happy to say that electricity is due to photons near a wire. But no-one is happy with my photons (electons) hugging a wire, even though electons tick the above 2 boxes (& nothing else comes close).

I reckon that the best experiment would be the simple speed of electricity along a threaded bar.
I doubt that the kind of metal would make much difference, eg steel copper aluminium, zinc plated nickel plated etc.
But a plastic coating would of course slow the electricity to say 2c/3.

I don’t know how u could make much scientific sense out of surface roughness, other than by using screw thread.
Very fine screw, medium screw, & very course screw. Whitworth thread. Bar thread.
Anyhow if i had a scope then the screw-thread test is what i would do first.
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