Which device is used to measure voltage?

The correct response highlights that the voltmeter is specifically designed to measure voltage. Voltage, also known as electric potential difference, is an essential electrical parameter that indicates the force pushing electric charges through a circuit. Voltmeters can be analog or digital and are generally connected across two points in an electrical circuit to obtain an accurate reading of the voltage present.

While a multimeter can also measure voltage, it is a multifunctional device that can perform various measurements including current and resistance. However, when the question specifically asks about the primary device employed to measure voltage, the voltmeter is the most direct and appropriate answer. This precise designation is critical, especially for tasks requiring accuracy in voltage measurement.

The other devices listed have distinct functions. An ohmmeter primarily measures resistance, while an ammeter measures the current flowing through a circuit. These specific roles underscore why they do not directly fulfill the requirement of measuring voltage.