Which instrument is used to measure electrical voltage?

Which instrument is used to measure electrical voltage?

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

Answer: (A)

Measuring voltage means assessing the potential difference between two points in a circuit. A voltmeter is designed for this job, reading in volts and used by connecting it across the two points where you want to know the voltage. Its high internal resistance is key: it draws very little current, so it doesn’t disturb the circuit’s operation while you measure. By comparison, an ammeter measures current and is placed in series so all the current flows through it; an ohmmeter measures resistance and is used when the circuit is unpowered to avoid damage; a barometer measures atmospheric pressure, not electrical quantities.

Measuring voltage means assessing the potential difference between two points in a circuit. A voltmeter is designed for this job, reading in volts and used by connecting it across the two points where you want to know the voltage. Its high internal resistance is key: it draws very little current, so it doesn’t disturb the circuit’s operation while you measure.

By comparison, an ammeter measures current and is placed in series so all the current flows through it; an ohmmeter measures resistance and is used when the circuit is unpowered to avoid damage; a barometer measures atmospheric pressure, not electrical quantities.