What is the purpose of a capacitor in electrical systems?

The primary purpose of a capacitor in electrical systems is to store and release electrical energy. Capacitors work by accumulating electrical charge on their plates when a voltage is applied, allowing them to store energy. This stored energy can be released back into the circuit when needed, making capacitors essential for various applications such as smoothing out voltage fluctuations, filtering signals, and providing bursts of energy for circuits that require a quick discharge of power.

This energy storage capability is particularly useful in power supply circuits, where capacitors can help maintain a steady voltage output despite changes in the load. They are also used in timing applications and in coupling and decoupling signals due to their ability to block direct current (DC) while allowing alternating current (AC) to pass through.

Understanding the role of capacitors as energy storage devices helps clarify their function in different electrical and electronic applications and enhances comprehension of broader circuit behavior.