Question

The reading of A . C ammeter and voltage across capacitor in the given circuit are

• A. $5$ amp, $50V$
• B. $4$ amp, $40V$
• C. $3$ amp, $30V$
• D. 2 amp, $20V$

Answer 1

The correct option is A $5$ amp, $50V$

A.C ammeter reads the rms value of current
$i_{rms}=\frac{i_0}{\sqrt{2}}$
and $i_0=\frac{V_0}{Z}$

$V_0=100V$

$Z=\sqrt{R^2+(X_L-X_C{)}^2}$
$=\sqrt{{10}^2+{10}^2}=10\sqrt{2}\Omega$

$\Rightarrow i_0=\frac{V_0}{Z}=\frac{100}{10\sqrt{2}}=\frac{10}{\sqrt{2}}A$

$\therefore i_{rms}=\frac{10}{2}=5A$

Voltage across capacitor $V_C=i_{rms}\times X_C$
$=5\times 10=50V$