Electric charges of $+10\,\mu C, +5\,\mu C, -3\,\mu C$ and $+8\,\mu C$ are placed at the corners of a square of side $\sqrt{2}\,m$. The potential at the centre of the square is:

If four charges $+12 \text{ nC}, -20 \text{ nC}, +32 \text{ nC}$ and $-15 \text{ nC}$ are arranged at the four vertices of a square of side $\sqrt{2} \text{ m}$,then the net electric potential at the centre of the square due to these four charges is (in $\text{ V}$)

Two point charges $-q$ and $+q$ are located at points $(0,0,-a)$ and $(0,0, a)$ respectively. The electric potential at a point $(0,0, z)$,where $z>a$ is

Two thin coaxial rings,each of radius $a$ and having charges $+Q$ and $-Q$ respectively,are separated by a distance $s$. The potential difference between the centres of the two rings is:

The electric potential at the centre of two concentric half rings of radii $R_1$ and $R_2$,having the same linear charge density $\lambda$,is $(\varepsilon_0 = \text{permittivity of free space})$

$A$ particle of mass $m$ and charge $q$ is accelerated through a potential difference of $V$ volt. Its energy will be: