The potentials on the plates of a capacitor are $+20 \,V$ and $-20 \,V$. The charge on the plate is $40 \,C$. The capacitance of the capacitor is (in $\,F$)

The Earth is assumed to be a charged conducting sphere having volume $V$ and surface area $A$. The capacitance of the Earth in free space is ($\epsilon_{0} =$ permittivity of free space).

The capacitance (in $F$) of a spherical conductor with a radius of $1\, m$ is:

Two similar conducting balls having charges $+q$ and $-q$ are placed at a separation $d$ from each other in air. The radius of each ball is $r$ and the separation between their centres is $d$ $(d \gg r)$. Calculate the capacitance of the two-ball system.

The potentials of the two plates of a capacitor are $+10\,V$ and $-10\,V$. The charge on one of the plates is $40\,C$. The capacitance of the capacitor is........$F$.

The capacity of a spherical conductor in the $MKS$ system is: