
This will be divided equally, as the capacitor are

When the switch S is closed as shown in the figure (b), then the charges stored across positive plates capacitors 1 and be Q1 and Q2 . The same charges will be distributed across negative plates of capacitor 3 and 4. Let the potential at the negative terminal is zero, then the charges across capacirots 1, 2, 3 and 4 will be

Thus from (i) and (iii) V0 = 12V and thus the charges be

Thus when switch is zero, 12µF charge is passed through the switch.