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)

Another capacitor should be added in parallel to the first.

Answer 2

: 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.