Question

Twelve $1\Omega$ resistances are used as edges to form a cube. The resistance between two diagonally opposite corners of the cube is

• A. $\frac{5}{6}\Omega$
• B. $1\Omega$
• C. $\frac{6}{5}\Omega$
• D. $\frac{3}{2}\Omega$

Answer 1

The correct option is A $\frac{5}{6}\Omega$


$V_{ab}=\frac{i}{3}\times 1+\frac{i}{6}\times 1+\frac{i}{3}\times 1$
$\Rightarrow R_{eq}=\frac{V_{ab}}{i}=\frac{5}{6}\Omega$