Two identical charged spherical drops each of capacitance $C$ merge to form a single drop. The resultant capacitance
equal to $2C$
greater than $2C$
less than $2C$ but greater than $C$
less than $C$
A network of four capacitors of capacity equal to $C_1 = C, C_2 = 2C, C_3 = 3C$ and $C_4=4C$ are conducted to a battery as shown in the figure. The ratio of the charges on $C_2$ and $C_4$ is
A charge $q$ is placed at $O$ in the cavity in a spherical uncharge $d$ conductor. Point $S$ is outside the conductor. If the charge is displaced from $O$ towards $S$ still remaining with in the cavity,
Two capacitors $C_1$ and $C_2 = 2\,C_1$ are connected in a circuit with a switch between them as shown in the figure. Initially the switch is open and $C_1$ holds charge $Q$. The switch is closed. At steady state, the charge on capacitors will be
The charge $q$ on a capacitor varies with voltage as shown in figure. The area of the triangle $AOB$ is proportional to
Figures below show regular hexagons, with charges at the vertices, In which of the following cases the electric field at the centre is not zero.