Capacitor

Capacitor:

A capacitor is a passive electronic component consisting of a pair of conductors separated by a dielectric. When a voltage potential difference exists between the conductors, an electric field is present in the dielectric. This field stores energy and produces a mechanical force between the plates. The effect is greatest between wide, flat, parallel, narrowly separated conductors.

Dielectric:

A basic capacitor is made up of two conductors separated by an insulator, or dielectric. The dielectric can be made of paper, plastic, mica, ceramic, glass, a vacuum or nearly any other non conductive material. Some capacitors are called electrolytic, meaning that their dielectric is made up of a thin layer of oxide formed on an aluminum or tantalum foil conductor.

Cautions:

Capacitors may retain charge long after power is removed from a circuit; this ascribe can origin unsafe or even potentially mortal alarms or damage attached gear. For example, even an apparently innocuous apparatus such as a disposable camera flash unit driven by a 1.5 volt AA electric battery contains a capacitor which may be ascribed to over 300 volts. This is effortlessly adept of delivering a shock.