How does a multi-meter function?

A multi-meter is a versatile tool used for electrical measurements, and its primary function is to measure voltage, current, and resistance in a circuit. This capability makes it indispensable in diagnosing electrical issues, testing circuits, and verifying the performance of electrical components.

When measuring voltage, the multi-meter provides a reading of the electrical potential difference between two points in a circuit, allowing technicians to determine if devices are receiving the correct amount of power. For current measurements, the multi-meter can be connected in series with the circuit to gauge the flow of electrical charge, which is vital for understanding how much power is being used by the circuit. Additionally, when measuring resistance, the multi-meter can help identify faults in components like resistors and can be used to verify that circuits are open or closed.

The other choices do not accurately reflect the multi-meter's functions. While generating electrical power is a task for generators, and converting AC to DC is handled by rectifiers, neither is a function of a multi-meter. Furthermore, a multi-meter's ability to measure only resistance would limit its utility significantly, as it's designed to perform multiple measurement functions in one device.