Question

An a.c. supply of 100 volts is applied to a capacitor of capacitance 20 $\mu$ F. If the current in the circuit is 0.628 A, the frequency of a.c. must be

• A. 50 Hz
• B. 60 Hz
• C. 25 Hz
• D. 40 Hz

Answer 1

The correct option is A 50 Hz

$Y=100V,C=2\mu F=20\times {10}^{-6}$
$I=0.628A,v=?$
$X_C=\frac{V}{I}=\frac{100}{0.628}$
$\Rightarrow \frac{1}{2\pi vC}=\frac{100}{0.628}$
$v=\frac{0.628}{100\times 2\pi C}$
$=50Hz$