Question

Six cells, each of emf \(5\) V and internal resistance \(0.1\ \Omega\) are connected as shown in the figure. The ideal voltmeter \(V\) records the value

• A. \(30\) V
• B. \(5\) V
• C. \(15\) V
• D. zero
• E. \(0.5\) V

Hint:

In symmetric cell arrangements, check whether the two voltmeter points are at the same potential before doing long calculations.

Answer 1

The Correct Option is D

From the scanned figure on page 12, the six identical cells are arranged symmetrically in a closed loop. Because the voltmeter is ideal and the effective potential difference between the two measured points becomes zero by symmetry, the voltmeter reads zero. Hence, \[ \boxed{(D)\ \text{zero}} \]