In an electrical circuit, what does a capacitor do?

A capacitor is a passive electrical component that serves the important function of storing electrical energy in an electric field. When a voltage is applied across the terminals of a capacitor, it accumulates charge on its plates, which allows it to hold energy. This stored energy can be released back into the circuit when needed, making capacitors crucial for various applications, such as smoothing out voltage fluctuations in power supplies, filtering signals in electronics, and providing quick bursts of energy in timing applications.

In contrast, capacitors do not generate electrical energy; they only store it. They do not measure voltage levels directly, as measuring instruments like voltmeters are designed for that purpose. Moreover, while capacitors provide some impedance to the current due to their reactance, they do not provide resistance in the way resistors do, as resistance relates to energy dissipation. Thus, understanding the role of a capacitor as a storage device that can release energy when necessary is essential in grasping its function within electrical circuits.