Question

A uniform wire of $16\Omega$ resistance is made into the form of a square. Two opposite corners of the square are connected by a wire of resistance $16\Omega$. The effective resistance between the other two opposite corner is

• A. $32\Omega$
• B. $16\Omega$
• C. $8\Omega$
• D. $4\Omega$

Answer 1

The correct option is D $4\Omega$

The circuit will be as shown in figure. It is a balanced wheatstone bridge, so the effect of 16 $\Omega$ resistance will be absent.

Then effective resistance between A and B is $R_{AB}=(4+4)\parallel (4+4)\Omega =8\parallel 8\Omega$

$⟹$ $R_{AB}=\frac{8\times 8}{8+8}=4\Omega$