Question

In the given figure, the equivalent resistance between two points A and B will be:

• A. $4\Omega$
• B. $2\Omega$
• C. $8\Omega$
• D. $6\Omega$

Answer 1

The correct option is D $6\Omega$

$\text{Given:}$

$R_1=2\Omega ,R_2=4\Omega ,R_3=4\Omega ,R_4=2\Omega$

$\text{Step 1: Combining parallel resistances}$

$R_2$ and $R_3$ are in parallel(Refer figure).

$R_a=\frac{R_2{R}_3}{R_2+R_3}=\frac{4\times 4}{4+4}=2\Omega$

$\text{Step 2: Combining series resistances}$

$R_4,R_a$ and $R_1$ are in series(Refer figure).

$R_{AB}=R_1+R_a+R_4$

$=2\Omega +2\Omega +2\Omega =6\Omega$

The equivalent resistance between A and B is $6\Omega$

Hence, Option(D) is correct.