Question

In the given figure the steady state current in the circuit is

• A. Zero
• B. 0.6 A
• C. 0.9 A
• D. 1.5 A

Answer 1

Answer: (D)

In the steady state there is no current in the capacitor branch.
In the given circuit the resistors of $2\, \Omega$ and $3\, \Omega$ are connected in parallel hence, equivalent resistance is
$\frac{1}{R}=\frac{1}{2}+\frac{1}{3}=\frac{5}{6} $
$\therefore R '=\frac{6}{5} \,\Omega$
Also in steady state, the circuit is shown as. Resistors of $\frac{6}{5} \,\Omega$ and $2.8\, \Omega$ are connected in series
Hence, $R ''=\frac{6}{5} \Omega+2.8 \,\Omega$
$=1.2 \Omega+2.8 \,\Omega$
$=4.0\, \Omega$
From Ohms law, Current $i=\frac{V}{R}=\frac{6}{4.0}=1.5\, A$