Passive Electronic Components - Capacitor Passive Electronic Components - Capacitor

Passive Electronic Components - Capacitor


A capacitor (originally known as a condenser) is a passive two-terminal electrical component used to store energy electrostatically in an electric field. The forms of practical capacitors vary widely, but all contain at least two electrical conductors (plates) separated by a dielectric (i.e. insulator). The conductors can be thin films, foils or sintered beads of metal or conductive electrolyte, etc. The “nonconducting” dielectric acts to increase the capacitor’s charge capacity. A dielectric can be glass, ceramic, plastic film, air, vacuum, paper, mica, oxide layer etc. Capacitors are widely used as parts of electrical circuits in many common electrical devices. Unlike a resistor, an ideal capacitor does not dissipate energy. Instead, a capacitor stores energy in the form of an electrostatic field between its plates. When two capacitors are connected in parallel as then their total capacitance equals the sum of individual capacitance.

Capacitance: The amount of charge that can be stored inside a capacitor at a given voltage is called Capacitance. It gets charged when charges are forced into the positive (or upper) plate of the capacitor due to emf. Similarly, it discharged when charges are forcefully pulled out of the capacitor. Capacitance is measured in Farad.