Resistance is measured with a voltmeter.

• A. True
• B. False
• C. Sometimes
• D. Not applicable

Answer: (B)

Measuring resistance requires an instrument that either injects a small current and measures the resulting voltage, or uses internal circuitry to compute resistance from readings. An ohmmeter (or a multimeter in resistance mode) does this by applying a known current and calculating resistance from Ohm’s law. A voltmeter, by contrast, is designed to measure voltage across two points and is connected in parallel with a component; it has a high input impedance so it doesn’t disturb the circuit, but it does not provide the data needed to determine resistance. So resistance is not measured with a voltmeter. Use an ohmmeter or the resistance setting on a multimeter, and ensure the circuit is de-energized before measuring.