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

(Take $\pi \mathit{=}\frac{\mathit{22}}{\mathit{7}}$)