Question

how does a capacitor exactly work ?

Answer 1

The average capacitor is made up of a few things. There are two lead wires, the case, two metal plates of a specific size, and the dielectric.

The way capacitance works is by having two metallic plates separated by a material called the dielectric. The dielectric must be a nonconductive (insulating, opposes flow of electricity) material. There are several types of dielectrics such as paper, plastics, ceramic, glass, and even air.

When the capacitor is place in a circuit with an active current, the electrons from the negative side build up on the closest plate(the negative flows to the positive, that is why the negative is the active lead, although many capacitors are not polarized). Once the plate can no longer hold them, they are forced past the dielectric and onto the other plate, thus displacing the electrons back into the circuit. This is called the discharge.

Hope this give you the explanation u wanted.......☺

Answer 2

actually, you can have capacitance with a single plate or sphere also. It takes work to move like charges into proximity with each other. That work is dome by some external engine, like a battery. That energy if stored in the electric field, and can be recovered