What does a voltmeter measure?

• A. Current in a circuit
• B. Resistance across a component
• C. Voltage drop in a circuit
• D. Power consumption

Answer: (C)

A voltmeter is specifically designed to measure the voltage across two points in an electrical circuit, which is often referred to as the voltage drop. When a voltmeter is connected in parallel with a component or part of a circuit, it measures the electric potential difference between those two points, thus indicating how much voltage is being used or lost across that component.

The voltage measurement is crucial for understanding circuit behavior and ensuring that components operate within their specified voltage ranges. By measuring voltage, operators can diagnose issues such as inadequate supply voltage, which may cause devices to fail or perform poorly. This capability makes the voltmeter an essential tool in electronics and electrical engineering.