What is the function of a voltmeter?

The function of a voltmeter is to measure the voltage across two points in a circuit. Voltage, also known as electric potential difference, is a critical parameter in electrical systems as it determines the force that drives electric current through the circuit. By connecting the voltmeter in parallel with the two points where the voltage needs to be measured, it accurately displays the potential difference.

Understanding the role of a voltmeter is essential for troubleshooting circuits, performing electrical diagnostics, or simply ensuring that the voltage levels are within acceptable ranges for safe operation. This capability is fundamental for electrical apprentices, as voltage measurements can indicate whether components are functioning correctly or if there are issues within the circuit.

The other options refer to different instruments or measurements. Measuring current flow pertains to an ammeter, while resistance is measured by an ohmmeter. Power consumption is typically calculated using voltage and current measurements, but it is not directly measured by a voltmeter itself.