Which component is primarily used to measure electrical resistance in a circuit?

The component primarily used to measure electrical resistance in a circuit is the ohmmeter. This device is specifically designed for the sole purpose of determining the resistance of an electronic component or circuit, typically expressed in ohms.

An ohmmeter works by applying a small voltage through the resistor and measuring the resulting current flow, thereby enabling it to calculate the resistance based on Ohm's Law (V = IR). This functionality is essential in various applications, such as troubleshooting circuits, testing resistors, and ensuring components are functioning correctly.

In contrast, an ammeter is used to measure the current flowing through a circuit, a voltmeter measures the voltage across two points, and a wattmeter gauges the power consumed in a circuit. Each of these devices serves a different purpose and is not suitable for directly measuring resistance, highlighting the specialized role of the ohmmeter in electrical measurement.