$A$ non-uniformly shaped conductor is charged. Then,at its sharpest point:

In the absence of other conductors,the surface charge density is:

Three identical metal plates with large surface areas are kept parallel to each other as shown in the figure. The leftmost plate is given a charge $Q$,the rightmost a charge $-2Q$,and the middle one remains neutral. Find the charge appearing on the outer surface of the rightmost plate.

If a solid and a hollow conducting sphere have the same radius, then:

If on two concentric hollow spheres of radii $r$ and $R$ $(R > r)$,the total charge $Q$ is distributed such that their surface charge densities are equal,then the potential at their common centre is:

The linear charge density on the upper half of a segment of a ring is $\lambda$ and on the lower half,it is $-\lambda$. The direction of the electric field at the centre $O$ of the ring is: