Question

Three identical capacitors $C1,C2$ and $C3$ of capacitance $6mF$ each are connected to a $12V$ battery as shown
Find:
charge on each capacitor
equivalent capacitance of the network
energy stored in the network of capacitors

Answer 1

charge on each capacitor

capacitors $C_1$ and $C_2$ are in series.

$=\frac{C_1{C}_2}{C_1+C_2}=\frac{6\times 6}{6+6}=3\mu F$

charge on $C_1=3\mu \times 12=36\mu C$

charge on $C_2=3\mu \times 12=36\mu C$

charge on $C_3=6\mu \times 12=72\mu C$

equivalent capacitance of the network

$=3+6=9\mu F$

energy stored in the network of capacitors

$=\frac{1}{2}C{V}^2=\frac{1}{2}\times 9\times {12}^2=648\mu W$