Question

In the given circuit, potential difference between Points A and B is

• A. 6.7 V
• B. 3.7 V
• C. 4 V
• D. 10 V

Answer 1

Answer: (B)

Let $I_1$ is current flowing through first loop
$\therefore I_1=\frac{2}{3+2}=\frac{2}{5}A$

and $I_2$ is current flowing through the second loop
$\therefore I_2=\frac{4}{3+5}=\frac{1}{2}A$
Let $V_A$ is potential of point $A$ and $V_B$ is potential of point $B$
Now, we apply Kirchhoff’s law between points $A$ and $B$,
$\therefore V_A-3I_1-4+3I_2=V_B$
$\Rightarrow V_A-V_B=3\times \frac{2}{5}+4-3\times \frac{1}{2}$
$=\frac{12+40-15}{10}=\frac{37}{10}$
$\Rightarrow V_A-V_B=3.7V$