What does an ohmmeter measure?

An ohmmeter measures electrical resistance, which is the opposition that a material offers to the flow of electric current. The unit of measurement for resistance is ohms. When you use an ohmmeter, it applies a small known voltage to the circuit and measures the current that flows through it. Using Ohm's Law (V = I × R), the device can calculate the resistance (R) by rearranging the equation to R = V/I.

Understanding resistance is crucial in electrical and electronic applications since it impacts how components function in a circuit. Resistance affects everything from the performance of simple electrical devices to complex circuits in machinery, making it essential knowledge for a Mechanical Technologist. An ohmmeter plays a vital role in troubleshooting electrical circuits as it helps identify faulty components by revealing whether they have high, low, or infinite resistance, which indicates a break in the circuit.