No current flows between two charged bodies connected together when they have the same

If $27$ charged water droplets, each of radius $10^{-3} \,m$ and charge $10^{-12} \,C$ coalesce to form a single big spherical drop, then the potential of the big drop is (in $\,V$)

$64$ identical drops each charged up to a potential of $10 \, mV$ are combined to form a bigger drop. The potential of the bigger drop will be $.......... \, mV$.

The electric potential at the centre of two concentric half rings of radii $R_1$ and $R_2$,having same linear charge density $\lambda$ is

The figure shows three circular arcs,each of radius $R$ and total charge as indicated. The net electric potential at the centre of curvature is

Ten electrons are equally spaced and fixed around a circle of radius $R$. Relative to $V = 0$ at infinity,the electrostatic potential $V$ and the electric field $E$ at the centre $C$ are