Question

An LCR circuit contains R = 50Ω , L = 1 mH and C = 0.1 μF. The impedance of the circuit will be minimum for a frequency of

• A. $\frac{10^{5}}{2\pi}s^{- 1}$
• B. $\frac{10^{6}}{2\pi}s^{- 1}$
• C. $2\pi \times 10^{5}s^{- 1}$
• D. $2\pi \times 10^{6}s^{- 1}$

Answer 1

Answer: (A)

$\frac{10^{5}}{2\pi}s^{- 1}$

Answer 2

Impedance of LCR circuit will be minimum at resonant frequency so

$\nu_{0} = \frac{1}{2\pi\sqrt{LC}}$ $= \frac{1}{2\pi\sqrt{1 \times 10^{- 3} \times 0.1 \times 10^{- 6}}}$

$= \frac{10^{5}}{2\pi}Hz$