I often make mistakes but that won't stop me from pursuing the truth.

Frankly, I am learning it's best to just stay out of conversations like this until I gather 100 years worth of experience. It is clear my opinions are rudimentary compared to life long engineers.

Folks have made me sorry more than once for my input which is unfortunate as I enjoy discussing things that I do and do not know.

Carry on without me!

Don't ever stop. It's always good to hear a fresh voice with a hunger. It makes you remember things forgotten over the years.

 

What is important is to understand that most of the participants have poor mind reading skills and so questions need to include context as well as just the question. Otherwise you will be getting answers to the wrong question.
And if you are guessing at an answer, clarify it by stating the basis of your guess. Then folks will understand the context of your answer and it can make more sense.

 

OK, good question about "charge".
The charge on a capacitor is equal to the number of electrons that flowed into it to establish the electrical potential present between the two connections. To avoid dealing with huge numbers of tiny things, charge is usually expressed in units of coulombs, each coulomb being equal to a quite large number of electrons, and volts, although voltage is included to make the term more useful. Other descriptions may include additional nomenclature. Consider the charge on phototflash storage capacitors, which is often expressed in wattseconds. (voltage Xcurrent x time), with current= electrons per second.
In the context of my comments, "charge" is the number of coulombs stored in the capacitor that are able to be delivered out from the capacitor.

 

I would only add that coulombs is a measure of the charge differential (electrical force as a imbalance of charge) plate to plate in a typical electronic capacitor in a circuit. For every electron that flowed into the capacitor on a plate, one electron flowed out the other plate so the total number of charges inside the capacitor doesn't change.

Do capacitors store charge?
Capacitors do not store charge. Capacitors actually store an imbalance of charge. If one plate of a capacitor has 1 coulomb of charge stored on it, the other plate will have −1 coulomb, making the total charge (added up across both plates) zero. If you short circuit the capacitor by connecting the two plates with a wire of negligible resistance, you’ll see a sudden rush of current (depending on the size of the capacitor, this can result in sparks) as the electrons on the −1 coulomb plate rush onto the +1 coulomb plate. This sudden rush of current releases all the energy that’s stored in the capacitor.

https://www.khanacademy.org/science...ors store charge?,up across both plates) zero.

 

I would only add that coulombs is a measure of the charge differential (electrical force as a imbalance of charge) plate to plate in a typical electronic capacitor in a circuit. For every electron that flowed into the capacitor on a plate, one electron flowed out the other plate so the total number of charges inside the capacitor doesn't change.

https://www.khanacademy.org/science/in-in-class-12th-physics-india/in-in-electrostatic-potential-and-capacitance/x51bd77206da864f3:capacitance-parallel-plate-capacitors/a/capacitors-article#:~:text=Do capacitors store charge?,up across both plates) zero.

Capacitors certainly store potential energy, and it is very convenient to reference it as a charge. Functionally, it is the equal to a charge, as it will supply a current to hold a voltage constant, or at least, hold a voltage towards constant.

 

Capacitors certainly store potential energy, and it is very convenient to reference it as a charge. Functionally, it is the equal to a charge, as it will supply a current to hold a voltage constant, or at least, hold a voltage towards constant.

Sure, we use the word charge as energy in circuit theory about capacitors but charge is not electrical energy physically in a capacitor, the electric field is. When charge has kinetic energy converted from electrical energy in a capacitor, well , sparky, hot things usually happen.

 

From wiki:

The SI derived unit of quantity of electric charge is the coulomb (symbol: C). The coulomb is defined as the quantity of charge that passes through the cross section of an electrical conductor carrying one ampere for one second.[6] This unit was proposed in 1946 and ratified in 1948.[6] In modern practice, the phrase "amount of charge" is used instead of "quantity of charge".[7] The lowercase symbol q is often used to denote a quantity of electricity or charge. The quantity of electric charge can be directly measured with an electrometer, or indirectly measured with a ballistic galvanometer.

The amount of charge in 1 electron (elementary charge) is defined as a fundamental constant in the SI system of units, (effective from 20 May 2019).[8] The value for elementary charge, when expressed in the SI unit for electric charge (coulomb), is exactly 1.602176634×10−19 C

Thus a capacitor does not store charge as current does not flow during open circuit.

Of course some current will always flow as leakage due to a conductive medium (the dielectric) so my question becomes: Can an open circuit capacitor release energy with an ideal vacuum as the dielectric (infinite resistance)? I would think not.

 

From the reference above it would seem it's appropriate to say we can charge and discharge a capacitor yet the capacitor doesn't store charge rather potential energy. How confusing indeed. I think I've shown how the term is bastardized?

 

Hi
Please keep On Topic, ie: Capacitor and DC Blocking.

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