Two thin concentric hollow conducting spheres of radii $R_1$ and $R_2$ bear charges $Q_1$ and $Q_2$ respectively. If $R_1 < R_2$, then the potential of a point at a distance $r$ from the centre $(R_1 < r < R_2)$ is
$\frac{1}{{4\pi {\varepsilon _0}}}.\frac{{{Q_1} + {Q_2}}}{r}$
$\frac{1}{{4\pi {\varepsilon _0}}}.\left( {\frac{{{Q_1}}}{r} + \frac{{{Q_2}}}{{{R_2}}}} \right)$
$\frac{1}{{4\pi {\varepsilon _0}}}.\left( {\frac{{{Q_1}}}{{{R_1}}} + \frac{{{Q_2}}}{{{R_2}}}} \right)$
$\frac{1}{{4\pi {\varepsilon _0}}}.\left( {\frac{{{Q_1}}}{{{R_1}}} + \frac{{{Q_2}}}{r}} \right)$
An electric charge $10^{-3}$ $\mu C$ is placed at the origin $(0, 0) $ of $X - Y$ co-ordinate system. Two points $A$ and $B$ are situated at $\left( {\sqrt 2 ,\sqrt 2 } \right)$ and $(2,0)$ respectively. The potential difference between the points $A$ and $B$ will be.......$V$
Two charges $5 \times 10^{-8} \;C$ and $-3 \times 10^{-8}\; C$ are located $16\; cm$ apart. At what point $(s)$ on the line joining the two charges is the electric potential zero? Take the potential at infinity to be zero.
If a charged spherical conductor of radius $10\,cm$ has potential $V$ at a point distant $5\,cm$ from its centre, then the potential at a point distant $15\,cm$ from the centre will be
Figure shows the variation of electric field intensity $E$ versus distance $x$. What is the potential difference between the points at $x=2 \,m$ and at $x=6 \,m$ from $O$ is ............. $V$
A non uniformly shaped conductor is charged then at it's sharpest point