What is the primary function of an ohmmeter?

• A. To measure resistance in ohms
• B. To measure current
• C. To measure power consumption
• D. To measure temperature

Answer: (A)

An ohmmeter is designed to measure resistance in ohms. It passes a small current (or applies a small voltage) from its internal battery through the component and measures the response, then uses Ohm's law (R = V/I) to compute the resistance. This is why you’d use it to check a resistor, test for continuity, or verify insulation when the circuit is de-energized. It’s not used to measure current, power, or temperature—those require different tools or meter modes (current in series, power from voltage and current, temperature with a sensor).