Question

A $10\mu F$ capacitor is connected with an ac source $E=200\sqrt{2}\sin \left(100t\right)V$ through an ac ammeter (it reads rms value). What will be the reading of the ammeter ?

• A. $100mA$
• B. $300mA$
• C. $500mA$
• D. $200mA$

Answer 1

Answer: (D)

$200mA$

$I_0=\frac{V_0}{X_C}=\frac{200\sqrt{2}}{1/\omega C}$

$I_0=\frac{200\sqrt{2}}{1/(100\ast 10\ast {10}^{-6})}$

$I_0=200\sqrt{2}\ast {10}^{-3}A$

$I_{RMS}=\frac{I_0}{\sqrt{2}}$

$I_{RMS}=\frac{200\sqrt{2}\ast {10}^{-3}}{\sqrt{2}}=200mA$

Hence option 'D' is correct.