Current Electricity - Result Question 100

105. In the circuit shown the cells $A$ and $B$ have negligible resistances. For $V_A=12 V, R_1=500 \Omega$ and $R=100 \Omega$ the galvanometer $(G)$ shows no deflection. The value of $V_B$ is :

[2012]

(a) $4 V$

(b) $2 V$

(c) $12 V$

(d) $6 V$

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Answer:

Correct Answer: 105. (b)

Solution:

  1. (b)

Since deflection in galvanometer is zero so current will flow as shown in the above diagram.

current $I=\frac{V_A}{R_1+R}=\frac{12}{500+100}=\frac{12}{600}$

So $\quad V_B=I R=\frac{12}{600} \times 100=2 V$