In the circuit shown the cells A and B have negligible resistances. For VA = 12 V, R1 = 500 Ω and R = 100 Ω the galvanometer (G) shows no deflection. The value of VB is (a) 4 V (b) 2 V (c) 12 V (d) 6 V

Answer: (b). No current in G, so VA drives current only through R₁ and R, and p.d. across R equals VB. VB = VA (R)/(R₁ + R) = 12 × (100)/(600) VB = 2 V So the answer is (b) 2 V.

In the circuit shown the cells A and B have negligible resistances… | NEET 2012 (AIPMT, Prelims)

Q80NEET 2012 · AIPMT · PRELIMSMedium

Wheatstone Bridge & Metre Bridge

In the circuit shown the cells A and B have negligible resistances. For VA = 12 V, R1 = 500 $\Omega$ and R = 100 $\Omega$ the galvanometer (G) shows no deflection. The value of VB is

Show answer and solution

Answer: (b)

No current in G, so $V_A$ drives current only through $R_1$ and $R$ , and p.d. across $R$ equals $V_B$ .
$V_B = V_A \dfrac{R}{R_1 + R} = 12 \times \dfrac{100}{600}$
$V_B = 2$ V
So the answer is (b) $2$ V.

Report a mistake

Wheatstone Bridge & Metre Bridge question from NEET 2012 (AIPMT, Prelims)

More questions on Wheatstone Bridge & Metre Bridge