Three identical capacitors of capacitance $C$ each are connected in series and this connection is connected in parallel with one more such identical capacitor. The equivalent capacitance of the whole combination is:

Two condensers of capacity $0.3\,\mu F$ and $0.6\,\mu F$ respectively are connected in series. The combination is connected across a potential of $6\,V$. The ratio of energies stored by the condensers will be

Three parallel plate air capacitors are connected in parallel. Each capacitor has plate area $\frac{A}{3}$ and the separation between the plates is $d, 2d$ and $3d$ respectively. The equivalent capacity of the combination is ($\varepsilon_0 =$ absolute permittivity of free space).

Two capacitors $C_1$ and $C_2$ in a circuit are joined as shown in the figure. The potential of point $A$ is $V_1$ and that of point $B$ is $V_2$. The potential at point $D$ will be

What is the equivalent capacitance between points $A$ and $B$ in the given system?

In the connections shown in the adjoining figure,the equivalent capacitance between $A$ and $B$ will be......$\mu F$.