Seven capacitors, each of capacitance $2\,\mu F$ are to be connected to obtain a capacitance of $10/11\,\mu F$ .Which of the following combinations is possible ?

A thin square plate is placed in $x-y$ plane as shown in fig. such that is centre coinsides with origine it's charge density at point $(x, y)$ is $\sigma  = \sigma _0xy$ (where $\sigma _0$ is constant). Find total charge on the plate.

The adjoining diagram shows the electric lines of force emerging from a charged body. If the electric fields at $A$ and $B$ are $E_A$ and $E_B$ respectively and the distance between them is $r$, then

A solid spherical conducting shell has inner radius a and outer radius $2a$. At the center of the shell a point charge $+Q$ is located . What must the charge of the shell be in order for the charge density on the inner and outer surfaces of the shell to be exactly equal?

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

Two capacitors $C_1$ and $C_2$ are are charged to $120\, V$ and $200\, V$ respectively. It is found that by connecting them together the potential on each one can be made zero . Then