Extra exam question E5A04
Subelement E5, ELECTRICAL PRINCIPLES· Group E5A
What is the magnitude of the impedance of a parallel RLC circuit at resonance?
- A.Approximately equal to circuit resistance (correct answer)
- B.Approximately equal to inductive reactance
- C.Low compared to the circuit resistance
- D.High compared to the circuit resistance
WhyThe magnitude of a parallel RLC circuit's impedance at resonance is approximately equal to the circuit's resistance. At resonance in a parallel RLC circuit, the reactive branch currents cancel each other, leaving the circuit's impedance at its peak, dominated by and approximately equal to the circuit's resistance, the opposite behavior from a series resonant circuit, answer A. It isn't approximately equal to just the inductive reactance, and it's actually high, not low, compared to what a non-resonant frequency would show.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2024-2028 NCVEC Element 4 pool (public domain); the explanation above is original writing, see our methodology.
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