Question

An alternating voltage $V=V_0\sin \omega t$ is connected to a capacitor of capacity $C_0$ through an A.C. ammeter of zero resistance. The reading of ammeter is :

• A. $\frac{V_0}{\sqrt{2}}$
• B. $\frac{V_0}{\omega C\sqrt{2}}$
• C. $\frac{V_0\omega C}{\sqrt{2}}$
• D. $V_0\omega C$

Answer 1

The correct option is C $\frac{V_0\omega C}{\sqrt{2}}$

Alternating voltage is given as $V=V_o\sin wt$
Thus rms voltage $V_{rms}=\frac{V_o}{\sqrt{2}}$
Reactance of capacitance $X_C=\frac{1}{wC}$
So, reading of ammeter i.e. rms current flowing $I_{rms}=\frac{V_{rms}}{X_C}=\frac{V_{o}wC}{\sqrt{2}}$