Question

If the potential difference between $A$ and $D$ is $V$, what will be potential difference between $F$ and $C$. Each of the resistance is $R$.

• A. V/3
• B. V/4
• C. V/6
• D. V/8

Answer 1

Answer: (B)

$V=I{R}_{eq}=I\frac{4R}{3}$
or $I=\frac{3V}{4R}$.
$V_1=V_A-V_F=I\frac{R}{2}$
$V_2=V_A-V_C=I\left(\frac{R}{2}+\frac{R}{3}\right)=\frac{5}{6}IR$
$V_2-V_1=V_F-V_C=IR\left(\frac{5}{6}-\frac{1}{2}\right)=\frac{IR}{3}$
$V_F-V_C=\frac{IR}{3}=\left(\frac{4IR}{3}\right)\frac{1}{4}=\frac{V}{4}$