Question

A constant voltage at different frequencies is applied across a capacitance $C$ as shown in the figure. Which of the following graphs correctly depicts the variation of current with frequency?

• A.
• B.
• C.
• D.

Answer 1

The correct option is A

For capacitive circuits, we know that,
$X_C=\frac{1}{\omega C}$

Current
$I=\frac{\text{Voltage(V)}}{\text{Capacitive Reactance(}{X}_C\text{)}}$
$\Rightarrow I=\frac{V}{\frac{1}{\omega C}}=V\omega C$

For constant $V$ and $C$
$I\propto \omega$

Therefore, graph between $I$  and  $\omega$ would be a straight line with positive slope.

Hence, the correct option is (B).