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Veritasium "How Electricity Actually Works"
snarkysparky:
""The two or three capacitors in series are just one capacitor.""
Factually they are not!
I ask to consider the actual case where there are three distinct capacitors. And the middle one receives energy from somewhere.
If you don't think capacitors can transmit energy you should be able to explain this.
TimFox:
--- Quote from: electrodacus on May 25, 2022, 05:20:09 pm ---
--- Quote from: TimFox on May 25, 2022, 05:01:46 pm ---An interesting variation on case B is if you use double-sided aluminized Mylar for the center plate.
Back in grad school, when some of my buddies were building wire chambers for high-energy physics experiments, we considered using the tooling to build large electrostatic speakers, but the engineer in charge warned us that the double-sided Mylar film used in the chambers would burn out if we tried to use them for the membrane, since charge would have to flow through a very thin film to get from one side to the other as the membrane moved.
--- End quote ---
There will have been no reason for that not to work with low power. The wires mesh plates should have been fairly close to be an effective speaker but he should have allowed you to test this if nothing else will have been damaged other than worst case some inexpensive mylar tape.
--- End quote ---
As I remember it, the aluminized Mylar sheets were roughly 1 by 2 m, and the double-sided metallization was extremely thin (< 1 um). Power is a strange concept in electrostatic speakers (capacitive load), but we were planning to drive them with quite high voltages directly from the plates of 6DQ5 tubes. In our initial calculations, we had forgotten that the material available (for free) was double-sided. We were trying to take advantage of the tooling for stringing the wires on a glass-epoxy frame.
In your example case B, when the charge flows from the left to the right face of the central solid conductor, it flows through a huge cross-sectional area (width times height) compared with the Mylar case where it flows through an area that is wide but very thin.
electrodacus:
--- Quote from: snarkysparky on May 25, 2022, 07:02:34 pm ---""The two or three capacitors in series are just one capacitor.""
Factually they are not!
I ask to consider the actual case where there are three distinct capacitors. And the middle one receives energy from somewhere.
If you don't think capacitors can transmit energy you should be able to explain this.
--- End quote ---
What about two or three capacitors in parallel? They are factually two or three in parallel but is there any difference in functionality compared to a single larger capacity capacitor ?
Same thing applies for two or three in series is just that leakage is a bit of a problem as it will not be equal so they may charge a bit inequal and if used close to the voltage limit you will usually add some parallel resistors if used this way in a circuit.
When connecting identical capacitors in parallel you increase the plate area with distance remaining the same.
When connecting identical capacitors in series you just increase the distance between plates of the equivalent capacitor that is why capacity drops.
Example c) and example d) are identical with the exception that you can disconnect the two middle plates leaving you with 3 capacitors after you do that.
e) -| |_| |_| |-
Say you have e) so 3 capacitors in series but the one in middle has plates closer say 2x the capacity of those at the ends.
When you disconnect those 3 capacitors after you charged them
Do you think:
1) all have the same amount of energy stored equally divided.
2) the one in the middle contains twice as much energy as each of the other ones.
3) the one in the middle contains half of the energy each of the other two contain.
electrodacus:
--- Quote from: dunkemhigh on May 25, 2022, 07:00:58 pm ---
To be Frank I have no idea since I've given up following your diversions so haven't really looked at it. Also it seems a pretty pointless thing to consider since you're unlikely to replicate Derek's experiment with whatever shielding, so it just comes back to what you say would occur rather than what actually does.
--- End quote ---
I put in the effort to read what each one of you has to say. If you understand how capacitors and transmission lines work you will not need to even do the experiment to see that what I say holds true.
Likely you never seen any sort of shield that prevents a load getting energy from a source that is connected to load through wires. So you know for sure even without testing that lamp/resistor will receive energy from battery no matter what shield I create around.
The question is only if you think the shield that I proposed or any similar shield can stop energy getting to lamp/resistor in those first 65ns required for the energy to be delivered through the long wires.
Question is if this if proven true to you it is enough or you can still invent something to allow for energy transfer outside wire to still be true?
electrodacus:
--- Quote from: TimFox on May 25, 2022, 07:10:44 pm ---
As I remember it, the aluminized Mylar sheets were roughly 1 by 2 m, and the double-sided metallization was extremely thin (< 1 um). Power is a strange concept in electrostatic speakers (capacitive load), but we were planning to drive them with quite high voltages directly from the plates of 6DQ5 tubes. In our initial calculations, we had forgotten that the material available (for free) was double-sided. We were trying to take advantage of the tooling for stringing the wires on a glass-epoxy frame.
In your example case B, when the charge flows from the left to the right face of the central solid conductor, it flows through a huge cross-sectional area (width times height) compared with the Mylar case where it flows through an area that is wide but very thin.
--- End quote ---
That was a large sheet (not something I had in mind) and the double metalization will not have been helpful quite the opposite as mylar as outside layer will have helped reduce the risk of a discharge when sheet got to close to the grid. You also needs some sort of transformer to add audio signal.
Yes in my case b) the heat loss due to conduction is fairly small.
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