In electrical engineering, a capacitor is a device that stores electrical energy by accumulating electric charges on two closely spaced surfaces that are insulated from each other. The capacitor was originally known as the condenser, a term still encountered in a few compound names, such as the condenser microphone.
Capacitors are also known as Electric-condensers. A capacitor is a two-terminal electric component. It has the ability or capacity to store energy in the form of electric charge. Capacitors are usually designed to enhance and increase the effect of capacitance. Therefore, they take into account properties like size and shape.
Both capacitors and batteries store electrical energy, but they do so in fundamentally different ways: Capacitors store energy in an electric field and release energy very quickly. They are useful in applications requiring rapid charge and discharge cycles. Batteries store energy chemically and release it more slowly.
U is the electric potential energy (in J) stored in the capacitor’s electric field. This energy stored in the capacitor’s electric field becomes essential for powering various applications, from smartphones to electric cars (EVs). Dielectrics are materials with very high electrical resistivity, making them excellent insulators.
The utility of a capacitor depends on its capacitance. While some capacitance exists between any two electrical conductors in proximity in a circuit, a capacitor is a component designed specifically to add capacitance to some part of the circuit.
Most capacitors contain at least two electrical conductors, often in the form of metallic plates or surfaces separated by a dielectric medium. A conductor may be a foil, thin film, sintered bead of metal, or an electrolyte. The nonconducting dielectric acts to increase the capacitor's charge capacity.
OverviewTheory of operationHistoryNon-ideal behaviorCapacitor typesCapacitor markingsApplicationsHazards and safety
A capacitor consists of two conductors separated by a non-conductive region. The non-conductive region can either be a vacuum or an electrical insulator material known as a dielectric. Examples of dielectric media are glass, air, paper, plastic, ceramic, and even a semiconductor depletion region chemically identical to the conductors. From Coulomb''s law a charge on one conductor wil…