Question 96: AC fundamentals

Question

An inductor of inductance 2 $$\mathrm{\mu H}$$ is connected in series with a resistance, a variable capacitor and an AC source of frequency 7 kHz. The value of capacitance for which maximum current is drawn into the circuit $$\frac{1}{x}\mathrm{F}$$, where the value of $$x$$ is ___________.
(Take $$\pi=\frac{22}{7}$$)

Accepted Answer

Current drawn is maximum when circuit is in resonance.
$$\omega  = {1 \over {\sqrt {LC} }}$$
$$2\pi (7000) = {1 \over {\sqrt {2 	imes {{10}^{ - 6}}C} }}$$
$$ \Rightarrow C = {1 \over {3872}}F$$

AC fundamentals

Choose the correct answer: