In the shown wireframe, each side of a square (the smallest square) has a resistance $7 \mathrm{\Omega }$. What is the equivalent resistance value (in ohm) of the circuit between the points $\mathrm{A}$ and $\mathrm{B}$?

Solution

The circuit can be folded about $\mathrm{B}$ and redrawn as



Hence equivalent resistance between $\mathrm{A}$ and $\mathrm{B}$ is $2\mathrm{R}=2\times 7 \mathrm{\Omega }=14 \mathrm{\Omega }$.

Hence, the correct answer is 14.