Which instrument is used to measure voltage?

• A. Ammeter
• B. Voltmeter
• C. Ohmmeter
• D. Circuit Tester

Answer: (B)

The instrument used to measure voltage is the voltmeter. This device specifically measures the electrical potential difference between two points in a circuit. It is designed to be connected in parallel with the component across which the voltage needs to be measured. The voltmeter operates on the principle that it can read the voltage while drawing minimal current, ensuring that it does not significantly affect the circuit being tested.

Ammeter measures the current flowing through a circuit, not the voltage. An ohmmeter is used to measure resistance, while a circuit tester often checks for the presence of voltage but does not typically provide a precise measurement. Each of these instruments has a distinct function, and the voltmeter is uniquely suited for voltage measurement, making it the correct choice.