Question

For the circuit shown in the figure, the charge flown through the switch after it is closed is $nμC$ . Find the value of $n$ .

Answer 1

Initial charge on upper middle part of the circuit connected to switch,
$Q_{i}=0$
When switch is connected, both pair of $1μF$ and $4μF$ will be in parallel & both pairs will be at potential difference of $10V$ , hence charge on left side of the upper middle part(negative plate) $=1μF\times 10V=10μC$
and charge on right side of the upper middle part(positive plate) $=4μF\times 10V=40μC$
Hence, net charge on upper middle part now is $Q_{f}=-10+40=30μC$