How does a relay work?

A relay operates as an electromechanical switch that utilizes an electromagnet to control the opening and closing of a circuit. When an electric current passes through the coil of the electromagnet, it generates a magnetic field that pulls a switch armature, either making or breaking a connection in the circuit. This allows the relay to control a larger load using a smaller control signal, enabling safe and efficient operation of devices and circuits that require more power.

The purpose of a relay is to separate low-voltage control circuits from high-voltage load circuits, providing both safety and functionality. This mechanism allows it to switch devices on or off, making it an essential component in many electrical systems, including automation and control applications.

In contrast, other options do not accurately describe the primary function of a relay. Capacitors do store energy but are not used in the operation of relays in the same way. Converting alternating current to direct current is a different process involving rectification and is not related to how relays function. Finally, relays do not power appliances directly through a switch; rather, they control and manage the flow of electricity to those devices based on the signals they receive.