Question

In the circuit shown below, the switch $S$ is connected to position $P$ for a long time so that the charge on the capacitor becomes $q _{1}\, \mu C$. Then $S$ is switched to position $Q$. After a long time, the charge on the capacitor is $q _{2}\, \mu C$.

The magnitude of $q_1$ is ____.

Answer 1

After long time we can replace the capacitor by open circuit.

$i$ current in circuit $=1 / 3$ ampere
$v _{ AB }=2-2\left(\frac{1}{3}\right)=\frac{4}{3}$ volt
So, $q _{1}= CV =\frac{4}{3} \mu C$