Finding the charge on capacitors shown in a given circuit diagram

Question

In the circuit diagram in the image attached:

https://ibb.co/Kzwfs00

How can I find the charge on each of the capacitors shown.

Answer 1

Let V1, V2, V3, V4 be the voltages across the capacitors C1, C2, C3, C4 repectively.

We are to calculate V1, V2, V3, V4.

The two capacitors C1 and C2 connected in parallel have effective capacitance

C12 = C1 + C2 = 6μF

The two capacitors C3 and C4 connected in parallel have effective capacitance

C34 = C3 + C4 = 12μF

The two capacitors C12 and C34 are connected in series, therefore they have

the same voltage across them, which is ΔV = 24V.

The voltage ΔV across C12 gets divided between C1 and C2 according to their capacitances:

V1 = ΔV C1/C12 = 24×1/6 = 4V

V2 = ΔV C2/C12 = 24×5/6 = 20V

The voltage ΔV across C34 gets divided between C3 and C4 according to their capacitances:

V3 = ΔV C3/C34 = 24×8/12 = 16V

V4 = ΔV C4/C34 = 24×4/12 = 8V