ARRL Technician Practice Exam

What electrical component is used to connect or disconnect electrical circuits?

1. Resistor

2. Transistor

3. Switch

4. Capacitor

The correct answer is: Switch

A switch is the component specifically designed to connect or disconnect electrical circuits. It functions by allowing or interrupting the flow of electricity through a circuit, enabling users to control the operation of electrical devices. When a switch is turned on, it completes the circuit, allowing current to flow; when it's turned off, it breaks the circuit, stopping the flow of current. This functionality is fundamental in electrical systems, making switches vital for controlling power. In contrast, resistors are used to limit the amount of current that flows in a circuit and do not serve the purpose of connecting or disconnecting circuits. Transistors function as electronic switches or amplifiers but are more complex and not simply meant for direct switching; they control the flow of electrical signals. Capacitors store and release electrical energy but do not perform the function of connecting or disconnecting a circuit. Each of these components has a specific role, but the switch is uniquely designed for establishing or interrupting electrical connections directly.