Question

A resistor circuit is constructed such that twelve resistors are arranged to form a cube as shown in figure. Each resistor has a resistance of 2 ohm.
The potential difference of 30 V is applied across two of the opposing points as shown. If we replace resistors between A and B and resistors between G and H by resistors with wires of zero resistance, then the points having the same potential are :
(i) D, E, C, F (ii) A, B (iii) G, H

• A. only (i) is correct
• B. only (ii) is correct
• C. only (iii) is correct
• D. (i), (ii) and (iii) are correct

Answer 1

The correct option is D (i), (ii) and (iii) are correct

If no resistance is present between points A and B, and points G and H, they would be at same potential.

Hence the points 'A and B' and 'G and H' have same potential.

The modified circuit is symmetric about a plane passing through points B,D,H and F of the original circuit. Hence potential at those points is also same.