Advanced Qualification · A-001 Advanced theory · A-001-005-009
What is the Q of a parallel RLC circuit, if it is resonant at 3.625 MHz, L is 42 microhenrys and R is 220 ohms?
- A 4.35
- B 0.00435
- C 0.23
- D 2.3
Correct answer: C — 0.23. From the official ISED question bank, verified word for word.
Why
The value 0.23 is correct because the quality factor, or Q, for a parallel circuit measures how sharply it resonates by dividing the resistance by the reactance of the inductor at the resonant frequency. The full explanation — and one for every question — is in Pro.
Practise this section
Advanced theory: time constants, reactance, impedance, resonance, Q, and the mathematics behind tuned circuits.