The electric potential $V$ of a charged spherical shell depends on the distance $r$ from its center. Which of the following graphs represents this dependence?

The radius of a soap bubble whose potential is $16\,V$ is doubled. The new potential of the bubble will be.....$V$

$A$ point charge $q$ is held at the centre of a circle of radius $r$. $B$ and $C$ are two points on the circumference of the circle,and $A$ is a point outside the circle. If $W_{AB}$ represents the work done by the electric field in taking a charge $q_0$ from $A$ to $B$,and $W_{AC}$ represents the work done from $A$ to $C$,then:

The figure shows a positively charged infinite wire. $A$ particle of charge $q = 2 \, C$ moves from point $A$ to $B$ with constant speed. (Given linear charge density on the wire is $\lambda = 4 \pi \varepsilon_0$)

If eight identical drops are joined to form a bigger drop,the potential on the bigger drop as compared to that on the smaller drop will be:

$A$ charge $Q$ is distributed over two concentric hollow spheres of radii $r$ and $R$ $(R > r)$ such that their surface charge densities are equal. The potential at the common centre is