kapacitanskälla

A kapacitanskälla, often translated as capacitance source or simply a capacitor, is a passive two-terminal electrical component that stores electrical energy in an electric field. It consists of two conductive plates separated by a dielectric material, which is an electrical insulator. When a voltage is applied across the plates, positive charge accumulates on one plate and negative charge on the other, creating an electric field within the dielectric.

The ability of a capacitor to store charge is measured by its capacitance, denoted by the symbol C. Capacitance is defined as the ratio of the charge stored on either plate to the voltage difference between them: C = Q/V. The unit of capacitance is the farad (F). The capacitance of a capacitor depends on the area of the plates, the distance between them, and the dielectric constant of the material separating them.

Capacitors are fundamental components in electronic circuits and have numerous applications. They are used for filtering in power supplies, blocking direct current while allowing alternating current to pass, energy storage in flash photography and defibrillators, and as timing elements in oscillators and integrated circuits. They can also be used for tuning in radio receivers. In essence, a capacitor acts as a temporary reservoir for electrical energy.