Final answer:
An ohmmeter is used to measure the resistance of a component or device. It can measure the voltage across a component without current flowing.
Step-by-step explanation:
An ohmmeter is used to measure the resistance of a component or device. Ohmmeters can measure the voltage across a component without current flowing. The voltage difference across the component is measured using a constant current source, and the resistance is calculated using Ohm's law (R = V/I), where V is the voltage and I is the current.