Meters and troubleshootingQuestion 1187 of 1506

When is a Lissajous figure stable on the screen?

When the amplitudes are equal
When the two frequencies are in an exact integer ratio
When the signals are DC
When the phase is 0 degrees

Show answer

Correct answer: When the two frequencies are in an exact integer ratio

If the ratio is not exact, the figure slowly moves as the phase rolls.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 12.2: Frequency and Phase Measurement

Questions last reviewed: 18 October 2026

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