How is potential energy involved in Capacitors

[MedicalMan14]

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I don't understand where the mechanism for potential energy comes from. I understand the general idea behind Capacitors, but I'm hoping someone can give me a general outline/idea behind the Potential Energy within such.

 

[mflee]

Think of a capacitor as a storage of water in a tank within a stream or something (if you have examkrackers theres a picture of this). The capacitors storage of charge (it's storage of water) is it's potential to do work (release the charge/water to power whatever). Does that help?

 

[MedicalMan14]

Lol: I apologize, but I have the book here, and thats the very analogy which confuses me.

 

[badmintondr]

So..I think it would help to establish that capacitors pretty much take in energy, build it up, then release it as one huge burst. So maybe if you think about it in the terms of like... a container within a stream of XX, as the container gets filled up with XX, it tips over and releases a huge portion of XX. So, kinda see how its losing its KE kinda and gaining PE?

 

[MedicalMan14]

Um; I hate to annoy anyone but still no. I will continue to research this.

 

[badmintondr]

No worries! no one is annoyed lol, believe me, we all have our weaknesses. (Mine shall forever be electromagnetism)


Try this out: imagine you are an evil conqueror and you want to destroy this one town.
You are up in the mountains above their town where they have a giant dam/resevoir of water.
Imagine that the water that collects in this dam is similar to electricity.
You, the evil conqueror, need to release a sufficiently large amount of water (torrential) status to destroy the town so are you going to release little trickles of water?

NO! you are going to store up a huge amount and release it all at once. Lord of the Rings style.

This dam is similar to the capacitor in that it stores it and then releases it. So, if your "storing" Energy, can you see how potential energy plays a part in capacitor now?

And yes..my analogies are..not so medically relevant but hopefully it makes sense!

 

[MedicalMan14]

LOL! Well I understand, but what I don't understand is if it stores charge; How exactly does that relate to Energy?

 

[TieuBachHo]

LOL! Well I understand, but what I don't understand is it stores charge. How does that relate to Energy?

Electrical potential energy is the amount of work needed to move a charge from point A to B, right? If you put in more work to move a charge against its field, then that means you have more energy to do that work.

Think of it like when you shoot neutrons into a molecule, you would create a huge unstable amount of energy ready to burst. The same thing as charges, like charges don't like to stick together and ready to burst out.

 

[MedicalMan14]

Ok I'm almost there ! LOL. The one question I have left is; how is it moving a charge against its field. Does that mean it is moving - charges towards the - charged electric field capacitor plate?

 

[TieuBachHo]

Ok I'm almost there ! LOL. The one question I have left is; how is it moving a charge against its field. Does that mean it is moving - charges towards the - charged electric field capacitor plate?

OK 😀
Now, when I move the first electron onto a plate, it's an easy effort because there wasn't any there to force it out against my will. However, when I attempt to move a series of same charges onto the same plate, the resistance becomes fierce. So the charges already there forces it out against my will. Therefore, I would have to put more effort into doing that. Just keep a simple picture.

 

[MedicalMan14]

And there we go ladies and gentlemen, I understand this completely!!

THANK YOU greatly.