Meters and troubleshootingQuestion 1181 of 1506

How does a thermal true-RMS meter handle odd waveforms?

It applies a fixed sine-wave factor to the reading.
It measures resistor heat, so any shape works.
It reads only the peak value and scales it.
It counts the zero crossings in one second.

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Correct answer: It measures resistor heat, so any shape works.

The heating effect directly follows the definition of RMS, whatever the waveform.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 12.1: AC Voltmeters and Ammeters

Questions last reviewed: 18 October 2026

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