Question

Six equal resistances each of $4\Omega$ are connected to form a figure. The resistance between two corners $A$ and $B$ is

• A. $4\Omega$
• B. $4/3\Omega$
• C. $12\Omega$
• D. $2\Omega$

Answer 1

Answer: (B)

Equivalent circuit of this combination of resistances is as shown in figure.
The effective resistance of arm
$EG=\frac{4\times 4}{4+4}=2\Omega$

Total resistance between $A$ and $B$ will be
$\frac{1}{R}=\frac{1}{4}+\frac{1}{4}+\frac{1}{4}=\frac{3}{4}$ or $R=\frac{4}{3}\Omega$