A charge $q$ is distributed uniformly on the surface of a sphere of radius $R$. It is covered by a concentric hollow conducting sphere of radius $2 R$. Charge on the outer suiface of the hollow sphere will be, if it is earthed

A solid conducting sphere has cavity, as shown in figure. A charge $+ {q_1}$ is situated away from the centre. A charge $+q_2$ is situated outside the sphere then true statement is

$IAn$ empty thick conducting shell of inner radius $a$ and outer radius $b$ is shown in figure.If it is observed that the inner face of the shell carries a uniform charge density $-\sigma$ and the surface carries a uniform charge density $ '\sigma '$

Choose the correct statement related to the potential of the shell in absence of $q_B$

Two spheres of radius $R$ and $2R$ having charge $Q$ and $2Q$ respectively are placed far away from each other. How much charge will flow when key $'k'$ is pressed ?

Two spherical conductors $A$ and $B$ of radii $1\ mm$ and $2\  mm$ are separated by a distance of $5\ cm$ and are uniformly charged. If the spheres are connected by a conducting wire then in equilibrium condition, the ratio of the magnitude of the electric fields at the surfaces of spheres $A$ and $B$ is

Given below are two statements.

Statement $I$ : Electric potential is constant within and at the surface of each conductor.

Statement $II$ : Electric field just outside a charged conductor is perpendicular to the surface of the conductor at every point.

In the light of the above statements, choose the most appropriate answer from the options give below.