Question:
The angular frequency of alterlating current in a L-C-R circuit is $100 \mathrm{rad} / \mathrm{s}$. The
components connected are shown in the figure. Find the value of inductance of the coil
and capacity of condenser.
Correct Option: 1
Solution:
(1)
Since key is open, circuit is series
$15=\mathrm{i}_{\mathrm{rms}}(60)$
$\therefore \mathrm{i}_{\mathrm{rms}}=\frac{1}{4} \mathrm{~A}$
Now, $20=\frac{1}{4} X_{\mathrm{L}}=\frac{1}{4}(\omega \mathrm{L})$
$\therefore \mathrm{L}=\frac{4}{5}=0.8 \mathrm{H}$
$\& 10=\frac{1}{4} \frac{1}{(100 C)}$
$C=\frac{1}{4000} F=250 \mu F$