What is the primary function of a capacitor in an electrical circuit?

The primary function of a capacitor in an electrical circuit is to store electrical energy temporarily. Capacitors can accumulate charge and discharge it as needed, which allows them to smooth out voltage fluctuations in circuits, provide power during brief interruptions, and filter signals in various applications. The ability to store energy is critical in applications such as power supply smoothing, timing circuits, and energy transfer in AC applications.

This understanding of how capacitors operate is foundational in electrical engineering and electronics, as it explains their role in maintaining efficient and stable circuit function. Other devices serve different functions—like resistors, which manage current and voltage levels; inductors, which store energy in magnetic fields; or transformers, which facilitate energy conversion—highlighting the unique purpose of capacitors in energy management in circuits.