Question

An inductance of 1 mH a condenser of 10 μF and a resistance of 50 Ω are connected in series. The reactances of inductor and condensers are same. The reactance of either of them will be

• A. 100 Ω
• B. 30 Ω
• C. 3.2 Ω
• D. 10 Ω

Answer 1

Answer: (D)

10 Ω

Answer 2

Given $\omega L = \frac{1}{\omega C} \Rightarrow$ $\omega^{2} = \frac{1}{LC}$

or $\omega = \frac{1}{\sqrt{10^{- 3} \times 10 \times 10^{- 6}}} = \frac{1}{\sqrt{10^{- 8}}} = 10^{4}$

$X_{L} = \omega L = 10^{4} \times 10^{- 3} = 10\Omega$