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

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electrodacus:

--- Quote from: Sredni on May 01, 2022, 10:00:44 pm ---You talk about the dielectric, while I talk about what happens INSIDE the plates.

Here: https://electronics.stackexchange.com/questions/532541/is-the-electric-field-in-a-wire-constant
I put some references in this answer. A good deal of that is freely available on the net. Try to read at least the essay by Chabay and Sherwood.

--- End quote ---

The link seems to be out for maintenance.
Have you properly read my replay ? Do you disagree with the simplification ?
If you do agree then is there anything other than energy transferred trough wires in the simplified example?
Plates are made of conductive materials so I do not get your comment about dielectric and INSIDE the plates (inside the plates means basically inside the wire).

Sredni:
Funny, the link opens fine on my side. Maybe local servers undergo maintenance at different times.
Yes, inside the plates means inside the wires and inside the resistor.
Your simplification is assuming a lot of things that are true in circuit theory but are not necessarily true in the physical systems we are considering. Wait for the site to go back online.

aetherist:

--- Quote from: aetherist on May 01, 2022, 10:28:37 am ---I detect a continuing love affair around here for lumped element transmission line models.  I wish to point out that there has never been any good correlation tween such a model & experiment for a DC transient of the Veritasium gedanken kind, albeit using 1000 m of Cu (AlphaPhoenix) or 22 m of Cu (Veritasium) or 8 ft of Cu (Howardlong) or any m or ft of Cu.
--- End quote ---

--- Quote --- Q6.  Why did the yellow trace start its main rise at  63.0 ns, when the speed of electricity along the 21 m Cu tube (10 m out plus 1 m spacing plus 10 m back) is  3.34 ns/m in air which demands that the rise should have been at 70.1 ns?  A delay of 63.0 ns suggests a tube Cu length of only  18.9 m (2.1 m too short).  Q6A. Why was the speed of electricity  10% faster than  c?
--- End quote ---

--- Quote from: antenna on May 01, 2022, 05:31:04 am ---re Q6: With all the complaints about the speed of light, has anyone included the meter of probe cable? Or its velocity factor? Just wondering...
--- End quote ---
 

--- Quote from: electrodacus on May 01, 2022, 05:07:57 am ---re Q6. I have not looked at the graph that closely and I do not know their exact setup and how accurate their length measurements where. But is also irrelevant.
--- End quote ---
[antenna]  The length etc of the probes sounds like it could be the problem. The probes might have accidentally deducted 2.1 m from the 21 m of Cu tubing. Especially if the velocity factor for a probe is 2c/3. But i don’t know much about any of this stuff, i don’t know what a scope or a probe or Cu tubing smell like. 
Is there some way of zeroing a scope to cater for the delay in the probes?

[electrodacus]  Veritasium says almost zero about the exact lengths, but i think that the total L of Cu tubing is  42 m.
I like the way that Veritasium has the tubing say  2.5 m above the ground, so that ground reflexions don’t spoil his measurement of the  3.3 ns delay. And then he duznt even show us (on his scope screen) where exactly we can see his measurement of his  3.3 ns delay.

Veritasium duznt tell us whether the Cu tubing has an enamel coating. We all know that the speed of electricity drops from  c/1 down to  2c/3 when a Cu tubing is painted or when it is insulated.

Which brings me to my main point today.  Duz a lumped element transmission line model allow input for the insulation on a wire?
Duz a lumped element transmission line model allow for ground reflexion?

Veritasium made much of Ben Watson's lumped element transmission line model. Actually i think that it was not a lumped element transmission line model, i think that it might have been a direct application of Maxwell.  Duzzenmadder.  The same question arises.  Duz his Maxwell TL model allow input for the insulation on a wire?

electrodacus:

--- Quote from: Sredni on May 01, 2022, 10:11:46 pm ---Funny, the link opens fine on my side. Maybe local servers undergo maintenance at different times.
Yes, inside the plates means inside the wires and inside the resistor.
Your simplification is assuming a lot of things that are true in circuit theory but are not necessarily true in the physical systems we are considering. Wait for the site to go back online.

--- End quote ---

Seems to work now. I will take a look.

Main claim made by Derek is that energy flow is outside the wire. That is just not true as should be clear with my example of a charged capacitor charging a discharged capacitor.

electrodacus:

--- Quote from: aetherist on May 01, 2022, 11:07:05 pm ---[electrodacus]  Veritasium says almost zero about the exact lengths, but i think that the total L of Cu tubing is  42 m.
I like the way that Veritasium has the tubing say  2.5 m above the ground, so that ground reflexions don’t spoil his measurement of the  3.3 ns delay. And then he duznt even show us (on his scope screen) where exactly we can see his measurement of his  3.3 ns delay.

Veritasium duznt tell us whether the Cu tubing has an enamel coating. We all know that the speed of electricity drops from  c/1 down to  2c/3 when a Cu tubing is painted or when it is insulated.

Which brings me to my main point today.  Duz a lumped element transmission line model allow input for the insulation on a wire?
Duz a lumped element transmission line model allow for ground reflexion?

Veritasium made much of Ben Watson's lumped element transmission line model. Actually i think that it was not a lumped element transmission line model, i think that it might have been a direct application of Maxwell.  Duzzenmadder.  The same question arises.  Duz his Maxwell TL model allow input for the insulation on a wire?

--- End quote ---

I do not think there is any enamel of the copper pipe (that will not be common as far as I know). Also even if there was a thin layer of enamel or paint it will not charge the capacitance in any significant way as there is about 1m of air in between.
Also even if capacitance was some other value (say closer pipes or anything like that it will still be irrelevant for the main question).
 
The transmission line model is very accurate and just a digitization of the real transmission line as you need finite element's in order to do the calculation.

So as mentioned the setup can be simplified to just a charged capacitor (in place of the battery or power supply) and a discharged capacitor that is paralleled to the charged capacitor to approximate the transmission line and even the load.
You can have the two discharged series capacitors with a resistor in the middle but since the resistor is just a wire with higher resistance is not needed and since two series capacitors are the same with a single half capacity capacitor the simplification is perfectly accurate to explain the fact that all energy from one capacitor to the other is transferred trough wires (capacitor plates are also wires).


When you connect a charged capacitor to a discharged capacitor you have two ideal capacitors in series with a resistance (ESR) so the charge capacitor is say at 20V and discharged capacitor at 0V then 20V is the drop on the series resistance ESR plus is you want a light bulb
Voltage will drop on the charged capacitor as it is discharged while the voltage on the discharged capacitor increases. The current is limited by the series resistance ESR plus lamp if you want to have one there.
There is no electric field in the discharged capacitor and the field is only present when there is a delta in electrons on the two plates.
The electric field has nothing to do with the energy transfer as that is done by electrons trough the wire and the electric field is the consequence of the electron imbalance.
No electron imbalance no electric field.

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