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Veritasium "How Electricity Actually Works"
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electrodacus:

--- Quote from: hamster_nz on May 17, 2022, 10:45:38 pm ---I agree that no electrons travel through the 1m space from one wire to the other, but it does not follow that no electrical energy travels through that 1m gap.

I am sure you agree that no electrons will pass through the two capacitors either side of the LED+Resistor. However, electrical energy does pass through the capacitors, and it does light the LED.  That energy is coming from the DC supply!


And as pointed out before, I can replace the LED+R with a third capacitor in series, and charge the middle capacitor from the DC supply, remove it form the circuit and measure it. It does have charge (and therfore energy), even though no electrons have moved through any of the capacitors.

--- End quote ---

No enenrgy pases trough capacitors.
What you see as work done on the LED is the result of electrons moving from the plate of first capacitor to a plate on the second capacitor as the two capacitors in series are charged from the supply.
If you disconnect the battery and then short the wires that were before connected to battery you are discharging the capacitors so electrons will flow back between the two plates making them neutral again.
IanB:

--- Quote from: electrodacus on May 17, 2022, 10:50:41 pm ---No enenrgy pases trough capacitors.
What you see as work done on the LED
--- End quote ---

Since it takes energy to do work, and the energy did not pass through the capacitors, how did it get from the battery to the LED?
electrodacus:

--- Quote from: IanB on May 17, 2022, 11:08:17 pm ---Since it takes energy to do work, and the energy did not pass through the capacitors, how did it get from the battery to the LED?

--- End quote ---

The LED is in series with the capacitor/capacitors so that is wasted energy during charging process.
Is the same as waste energy in the wires as they carry the energy from the source to the capacitors (energy storage device) you just add an LED and thus extra loss to the process of charging the capacitor.

Electrical energy travels through wires and travels through LED/lamp/resistor but does not travels through capacitor but in capacitor.
PlainName:

--- Quote from: electrodacus on May 17, 2022, 10:26:59 pm ---There are capacitors on both sides in Derek's experiment

--- End quote ---

Let's not complicate matters unnecessarily.

There is a power source, cap, resistor, return. That's it. We've decided the cap is the two wires 1m apart, and we've gone with your values for it. We know the resistor is converting energy to heat.

The only issue is that there is the 1m gap without wires in that circuit. What, exactly, is passing from the power supply side of the capacitor to the other side that lets the resistor heat up? It must be energy, mustn't it, since that's what everything ultimately reduces to.

So, if energy is not being transferred across that gap, what IS going across? That resistor isn't using nothing to heat up, you know.
electrodacus:

--- Quote from: dunkemhigh on May 17, 2022, 11:15:58 pm ---
--- Quote from: electrodacus on May 17, 2022, 10:26:59 pm ---There are capacitors on both sides in Derek's experiment

--- End quote ---

Let's not complicate matters unnecessarily.

There is a power source, cap, resistor, return. That's it. We've decided the cap is the two wires 1m apart, and we've gone with your values for it. We know the resistor is converting energy to heat.

The only issue is that there is the 1m gap without wires in that circuit. What, exactly, is passing from the power supply side of the capacitor to the other side that lets the resistor heat up? It must be energy, mustn't it, since that's what everything ultimately reduces to.

So, if energy is not being transferred across that gap, what IS going across? That resistor isn't using nothing to heat up, you know.

--- End quote ---

Electrons from the source flow through wires in to one plate of the capacitor. Same number of free electrons leave the plate on the other side of the capacitor and return to the source.
All energy flows through wires in to the plates that are also wires and no energy flows through the capacitor dielectric in this case 1m of air.
The resistor is nothing more than a wire with higher resistance so energy flows through it same as it flows through wires.
if source is disconnected this charge imbalance remains there and if you short this wires then electrons from one plate can travel to the other plate that has a deficit of electrons in order for both plates to become neutral so you are discharging the capacitor and current will flow in reverse through wires.

Electrons (charged particles) are the ones that carry the energy and they do so through wires.
While air even 1m of it can become conductive the potential (voltage) will need to be way higher than 20V so no energy was transferred outside the wires in Derek's experiment. 
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