Meters and troubleshootingQuestion 941 of 1506

A voltmeter is connected across a resistor in an AC series R-L circuit. Which form of the calculated voltage matches the meter reading?

The real part of the rectangular form
The imaginary part of the rectangular form
The sum of both rectangular parts
The polar magnitude of the voltage

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Correct answer: The polar magnitude of the voltage

Meters show the length of the vector, which is the polar magnitude, not its parts.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 3.3: Series Resistor-Inductor Circuits

Questions last reviewed: 18 October 2026

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