Question

In the circuit shown, the galvanometer shows zero deflections. The batteries have negligible internal resistance. The value of the resistor R is

• A. $200\Omega$
• B. $100\Omega$
• C. $500\Omega$
• D. $1000\Omega$

Answer 1

The correct option is B $100\Omega$


EDCFE: 2 = $i_2$ R as $i_1$ =0 ---- (1)
ABCFA : 12 – 500 $i_2-R{i}_2$ = 0 ------(2)
From (1) and (2) R = 100 ohms