Question

A 10$\Omega$resistance, 5mH coil and 10$\mu$F capacitor are joined in series. When a suitable frequency alternating current source is joined to the combination, the circuit resonates. If the resistance is halved the resonance frequency is

• A. halved
• B. doubled
• C. remains same
• D. quadrupled

Answer 1

Answer: (C)

remains same

Resonance frequency

$\omega =\frac{1}{\sqrt{LC}}$

$f=\frac{1}{2\pi }\times \frac{1}{\sqrt{LC}}$

So, it depends only on inductance and capacitance
So, by changing resistance there will not be any change in resonance frequency.