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Veritasium "How Electricity Actually Works"

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electrodacus:

--- Quote from: snarkysparky on May 19, 2022, 06:45:46 pm ---if current flows into one terminal of a capacitor and out the other terminal I think most of us here call that "through"  the capacitor.

Are you saying that this situation is not correctly described by using the word "through" to describe the currents ?

--- End quote ---

You are calling it through but that is incorrectly. Saying electrical current flows through dielectric is incorrect and you know that.
Try and solve the problem in post #701 and see if going "through" is helpful.
Electric current flows through a resistor but it will not flow through a capacitor but in and out as it is stored there not doing any work.

IanB:

--- Quote from: electrodacus on May 19, 2022, 06:08:05 pm ---Then say you connect a 5Ohm resistor and energy will go through wires and through resistor toal 6Ohms so 2A * 12V = 24W in one second it will be 24Ws delivered by the source and 24Ws all end as heat dissipated by wires and by resistor as energy travels through them.

Now say you leave the wires and instead of a resistor you connect a capacitor say it is 1000uF = 1mF and say internal DC ESR is basically zero to keep things simple.
--- End quote ---

No, this is the wrong question. Keep the resistor there and insert the capacitor as well, so you have both the resistor and the capacitor in series in the circuit. Now answer your questions below:


--- Quote ---a) How much energy will power supply deliver in one second after the discharged capacitor was connected ?
b) How much energy will end up as heat dissipated by wires and resistor?
c) How much energy is stored in the capacitor after this second?
d) How much energy is delivered by the source in the next second? so after first second ended and another second from that point.

--- End quote ---

snarkysparky:
a) How much energy will power supply deliver in one second after the discharged capacitor was connected ?
b) How much energy will end up as heat dissipated by wires?
c) How much energy is stored in the capacitor after this second?
d) How much energy is delivered by the source in the next second? so after first second ended and another second from that point.


The circuit you describe is basically  12V  zero impedance source,    1 ohm resistor ( both 0.5 ohm wires )  ,  and 1000 u capacitor all in series.

Vc  =  12 * ( 1 - exp(-R*C* t))

Vc  =  12 * (1 - exp(- 1 * 1000e-6* t)

plot of the energy stored in the capacitor vs time



electrodacus:

--- Quote from: IanB on May 19, 2022, 07:02:11 pm ---
--- Quote ---a) How much energy will power supply deliver in one second after the discharged capacitor was connected ?
b) How much energy will end up as heat dissipated by wires and resistor?
c) How much energy is stored in the capacitor after this second?
d) How much energy is delivered by the source in the next second? so after first second ended and another second from that point.

--- End quote ---

No, this is the wrong question. Keep the resistor there and insert the capacitor as well, so you have both the resistor and the capacitor in series in the circuit. Now answer your questions below:


--- End quote ---

Wires already have a resistance 1Ohm in total so it will not make any difference if you keep the 5Ohm resistor in series. If you want keep the resistor in series and solve the problem.

electrodacus:

--- Quote from: snarkysparky on May 19, 2022, 07:07:01 pm ---a) How much energy will power supply deliver in one second after the discharged capacitor was connected ?
b) How much energy will end up as heat dissipated by wires?
c) How much energy is stored in the capacitor after this second?
d) How much energy is delivered by the source in the next second? so after first second ended and another second from that point.


The circuit you describe is basically  12V  zero impedance source,    1 ohm resistor ( both 0.5 ohm wires )  ,  and 1000 u capacitor all in series.

Vc  =  12 * ( 1 - exp(-R*C* t))

Vc  =  12 * (1 - exp(- 1 * 1000e-6* t)

plot of the energy stored in the capacitor vs time

(Attachment Link)

--- End quote ---

The graph looks wrong (x axis) just answer the questions. Those are us so 5000us not 5000ms

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