What does a voltmeter measure?

A voltmeter is a device specifically designed to measure electrical potential difference, or voltage, between two points in an electrical circuit. When connected across components in a circuit, it provides a reading that indicates how much electrical potential energy exists per unit charge, expressed in volts. This property is crucial for understanding how electrical systems operate, as voltage is a fundamental parameter affecting current flow and overall circuit behavior.

The correct answer is based on the definition and function of the voltmeter, which directly aligns with measuring voltage. This distinguishes it from other instruments: an ammeter measures current, an ohmmeter measures resistance, and a wattmeter is used to measure power consumption. Thus, the voltmeter's primary role in measuring voltage makes it essential for analyzing and troubleshooting electrical circuits.