On rotating a point charge having a charge $q$ around a charge $Q$ in a circle of radius $r$. The work done will be
$q \times 2\pi r$
$\frac{{q \times 2\pi Q}}{r}$
Zero
$\frac{Q}{{2{\varepsilon _0}r}}$
A particle $A$ has charge $+q$ and particle $B$ has charge $+4 q$ with each of them having the same mass $m$. When allowed to fall from rest through the same electric potential difference, the ratio of their speeds $\frac{V_A}{V_B}$ will become
An alpha particle is accelerated through a potential difference of ${10^6}\,volt$. Its kinetic energy will be......$MeV$
Charge $q_{2}$ is at the centre of a circular path with radius $r$. Work done in carrying charge $q_{1}$, once around this equipotential path, would be
When one electron is taken towards the other electron, then the electric potential energy of the system
The charge given to any conductor resides on its outer surface, because