The capacitance $(C)$ for an isolated conducting sphere of radius $(a)$ is given by $4\pi \varepsilon_0a$. If the sphere is enclosed with an earthed concentric sphere. The ratio of the radii of the spheres $\frac{n}{{(n - 1)}}$  being then the  capacitance of such a sphere will be increased by a factor

The magnitude of electric field $E$ in the annular region of a charged cylindrical capacitor

This question has Statement $1$ and Statement $2$. Of the four choices given after the Statements, choose the one that best describes the two Statements.

Statement $1$ : It is not possible to make a sphere of capacity $1$ farad using a conducting material.
Statement $2$ : It is possible for earth as its radius is $6.4\times10^6\, m$

Two spherical conductors $A$ and $B$ of radii $a$ and $b$ $(b > a)$ are placed concentrically in air. The two are connected by a copper wire as shown in figure. Then the equivalent capacitance of the system is

Two conducting shells of radius $a$ and $b$ are connected by conducting wire as shown in figure. The capacity of system is :

Two spherical conductors $A$ and $B$ of radius $a$ and $b (b > a)$ are placed in air concentrically $B$ is given charge $+ Q$ coulomb and $A$ is grounded. The equivalent capacitance of these is