In an LCR circuit, capacitance is changed from C to 2C. For the resonant frequency to remain unchanged, the inductance should be changed from L to
Options
(a) 4 L
(b) 2 L
(c) L/2
(d) L/4
Correct Answer:
L/2
Explanation:
At resonance ω = 1 / √(LC)
Since ω is constant,
Therefore, LC = L’C’ = L’ × 2C
⇒ L’ = L / 2