일반물리학 2 — Electromagnetic Oscillations and Alternating Current: Problem 26

26 Figure 31-24 shows a driven RLC circuit that contains two identical capacitors and two switches. The emf amplitude is set at 12.0 V, and the driving frequency is set at 60.0 Hz. With both switches open, the current leads the emf by 25.0°. With switch $S_1$ closed and switch $S_2$ still open, the emf leads the current by 20.0°. With both switches closed, the current amplitude is 447 mA. What are (a) $R$, (b) $C$, and (c) $L$?