Question

A uniform wire of resistance $36ohm$, is bent inside a circle. A battery is connected between positions A and B as shown. The effective resistance between A and B is ?

Answer 1

The wire in bent to circle,

The simplified diagram will be

Refer image.

as the resistors of whole wire is $36\Omega$ so the resistors at ${60}^0$ are of circle will be

$\frac{60}{360}\times 36=6\Omega$

and at remaining part will be

$36-6=30\Omega$

$Reff=\frac{30\times 6}{30+6}=\frac{180}{36}=5\Omega$