Which instrument is primarily used to measure resistance and test continuity?

Which instrument is primarily used to measure resistance and test continuity?

• A. Multimeter
• B. Voltmeter
• C. Ohmmeter
• D. Ammeter

Answer: (C)

Measuring resistance is done by pushing a small current through the unknown path and checking the resulting response, which is exactly what an ohmmeter does. It either uses a built-in current source and measures voltage to calculate resistance, or in modern digital forms directly displays the resistance value. For continuity, the same instrument checks whether there’s a low-resistance path between two points and usually gives an audible beep when continuity exists. This combination—injecting a small current and reading the response to determine resistance and to confirm a complete path—is why the instrument specialized for this task is used. A voltmeter, by contrast, is meant to measure voltage and does not source current through the circuit. An ammeter measures current, not resistance. A multimeter can measure resistance and perform a continuity check, but the device most specifically associated with both resistance measurement and continuity testing is the ohmmeter. When using it, ensure the circuit is de-energized and the component is isolated to get an accurate reading.

Measuring resistance is done by pushing a small current through the unknown path and checking the resulting response, which is exactly what an ohmmeter does. It either uses a built-in current source and measures voltage to calculate resistance, or in modern digital forms directly displays the resistance value. For continuity, the same instrument checks whether there’s a low-resistance path between two points and usually gives an audible beep when continuity exists. This combination—injecting a small current and reading the response to determine resistance and to confirm a complete path—is why the instrument specialized for this task is used.

A voltmeter, by contrast, is meant to measure voltage and does not source current through the circuit. An ammeter measures current, not resistance. A multimeter can measure resistance and perform a continuity check, but the device most specifically associated with both resistance measurement and continuity testing is the ohmmeter. When using it, ensure the circuit is de-energized and the component is isolated to get an accurate reading.