What is the role of capacitors in electrical systems?

Capacitors play a crucial role in electrical systems primarily by storing and discharging electrical energy. They consist of two conductive plates separated by an insulating material (dielectric) that allows them to accumulate electrical charge when a voltage is applied across them. When the power supply is disconnected, capacitors can release the stored energy back into the circuit, providing a quick burst of energy when needed. This ability to store and release energy is fundamental in various applications, such as in smoothing out voltage fluctuations in power supplies, filtering signals in audio equipment, or maintaining power for momentary interruptions in supply.

Other functions such as transmitting signals, converting AC to DC, or regulating current flow are associated with different components like resistors, transformers, or diodes, which serve distinct purposes in electrical systems.