Q. If key $K_{1}$ is closed in circuit shown in figure-$3.342$ and galvanometer doesn't give deflection at any time, then value of $C$ is:

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A

$3\, \mu F$

B

$9\, \mu F$

C

$4 \,\mu F$

D

$1\, \mu F$

Solution:

For no current in galvanometer at any time including transient duration, then we use
$\Rightarrow \frac{2}{6}=\frac{\frac{1}{3}}{\frac{1}{C}}$
$\Rightarrow C=1 \,\mu F$

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