Question

Find the current $i$ in the circuit shown below.

• A. $1\text{A}$
• B. $3\text{A}$
• C. $\frac{3}{2}\text{A}$
• D. $\frac{1}{2}\text{A}$

Answer 1

The correct option is D $\frac{1}{2}\text{A}$


From the figure we can say that, the two $2\Omega$ resistances are in series with each other and their combination is in parallel with the $4\Omega$ resistance.
Therefore, the circuit diagram can be simplified as :


Here, again two $2\Omega$ resistances are in series with each other and their combination is in parallel with the $4\Omega$ resistance.
Therefore, we can say that the net resistance across the battery is $R_{eq}=4\Omega$

Hence, the current flowing through battery is given by :
$I=\frac{V}{R}=\frac{8}{4}=2\text{A}$

Assigning potentials to different points of the circuit.


From the figure we can say that current $i$ is given by :
$i=\frac{2-0}{4}=\frac{1}{2}\text{A}$