Question

The total current supplied to the given circuit by the battery is

• A. $9A$
• B. $6A$
• C. $2A$
• D. $4A$

Answer 1

Answer: (B)

The equivalent circuit of the given circuit is as shown

Resistances 6 $\Omega$ and 2 $\Omega$ are in parallel
$\therefore R^{\prime }=\frac{6\times 2}{6+2}=\frac{3}{2}\Omega$
Resistances $\frac{3}{2}\Omega and1.5\Omega areinseries$
$\therefore R^{\prime \prime }=\frac{3}{2}+1.5=3\Omega$
Resistances 3 $\Omega$ and 3 $\Omega$ are in parallel
$\therefore R=\frac{3\times 3}{3+3}=\frac{3}{2}$
The current, $I=\frac{V}{R}$
$=\frac{9}{3/2}=6\text{A}$