Meters and troubleshootingQuestion 710 of 1506

One resistor branch in a parallel circuit on an ideal voltage source goes open. What does the voltage across that branch do?

It doubles
It stays the same
It reverses polarity
It falls to zero

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Correct answer: It stays the same

The ideal source holds the voltage across all parallel branches, even when one branch is open.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 7.4: Component Failure Analysis (Continued)

Questions last reviewed: 18 October 2026

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