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 corners is

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

Answer 1

Answer: (D)

4$\Omega$

The situation is shown in adjacent figure. The sides of the square will be 4 ohm each and two opposite corner is connected by a resistance of 16 ohm. Due to the symmetry of the problem, we can ignore the 16 ohm resistance. So the resistance between other two opposite end (A-B) will be the effective resistance due to the two 8 ohm resistance in parallel i.e. 4 ohm.