Question

To reduce the resonant frequency in an $LCR$ series circuit with a generator

• A. the generator frequency should be reduced
• B. another capacitor should be added in parallel to the first
• C. the iron core of the inductor should be removed
• D. dielectric in the capacitor should be removed

Answer 1

Answer: (B)

Resonant frequency in a series $LCR$ circuit is
$\upsilon_{r}=\frac{1}{2\pi\sqrt{LC}}$
If capacitance $C$ increases the resonant frequency will reduce, which can be achieved by adding another capacitor in parallel to the first.