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

The main function of a capacitor in an electrical circuit is to store and release electrical energy. Capacitors achieve this by accumulating charge on two conductive plates separated by an insulating material called a dielectric. When voltage is applied across the capacitor, electric charge builds up on the plates, which can be later released back into the circuit as needed.

This energy storage capability is crucial in various applications, such as smoothing out fluctuations in power supply, filtering signals in audio applications, and providing brief bursts of energy in power supply circuits. Capacitors can quickly charge and discharge, making them vital components in timing circuits, oscillators, and energy storage systems.

In contrast, increasing voltage, amplifying signals, or acting as a resistor does not accurately describe the primary role of a capacitor. While capacitors may indirectly influence voltage levels in a circuit and play a role in filtering signals, their fundamental task is focused on energy storage and release.