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
Charge, distribution on outer surlace of sphere is uniform
Charge, distribution on inner surface of sphere is uniform
Magnitude of force on charge $q_2$ due to induced charge on inner surface of sphere is $\frac{{k{q_1}{q_2}}}{{\left( {\frac{R}{2} + l} \right)}}$
Magnitude of force on charge $q_2$ due to induced charge o n inner surface of sphere is $\frac{{k{q_1}{q_2}}}{{{{\left( l \right)}^2}}}$
A thin metallic spherical shell contains a charge $Q$ on it. A point charge $+q$ is placed at the centre of the shell and another charge $q'$ is placed outside it as shown in fig. All the three charges are positive. The force on the central charge due to the shell is :-
Assertion : In a cavity within a conductor, the electric field is zero.
Reason : Charges in a conductor reside only at its surface
The magnitude of electric field on the surface of a uniformly charged metalic spherical shell is $E$. If a hole is made in it using a insulating device, then the magnitude of electric field in the hole will be
$(a)$ A conductor $A$ with a cavity as shown in Figure $(a)$ is given a charge $Q$. Show that the entire charge must appear on the outer surface of the conductor.
$(b)$ Another conductor $B$ with charge $q$ is inserted into the cavity keeping $B$ insulated from $A$. Show that the total charge on the outside surface of $A \text { is } Q+q$ [Figure $(b)$]
$(c)\;A$ sensitive instrument is to be shielded from the strong electrostatic fields in its environment. Suggest a possible way.
A solid conducting sphere of radius $a$ has a net positive charge $2Q$. A conducting spherical shell of inner radius $b$ and outer radius $c$ is concentric with the solid sphere and has a net charge $-Q$. The surface charge density on the inner and outer surfaces of the spherical shell will be