Force between $A$ and $B$ is $F$. If $75\%$ charge of $A$ is transferred to $B$ then force between $A$ and $B$ is

A charge $q$ is placed at $O$ in the cavity in a spherical uncharge $d$ conductor. Point $S$ is outside the conductor. If the charge is displaced from $O$ towards $S$ still remaining with in the cavity,

A particle of mass $m$ and charge $q$ is placed at rest in a uniform electric field $E$ and then released. The $KE$ attained by the particle after moving a distance $y$ is

Charge $q$ is uniformly distributed over a thin half ring of radius $R$. The electric field at the centre of the ring is

Consider a system of there charges $\frac{q}{3},\,\frac{q}{3}$ and $-\frac{2q}{3}$ placed at point $A, B$ and $C,$ respectively, as shown in the figure. Take $O$ to be the centre of the circle of radius $R$ and $\angle CAB\, = \,{60^o}$

A hollow metal sphere of radius $5\, cm$ is charged so that the potential on its surface is $10\, V$. The potential at the centre of the sphere is.....$V$