Two hollow conducting spheres of radii $R_{1}$ and $R_{2}$ $(R_{1} >> R_{2})$ have equal charges. The potential would be:

If a $10 \mu C$ charge exists at the centre of a square,the work done in moving a $2 \mu C$ point charge from corner $A$ to corner $B$ of a square $ABCD$ is

There are three concentric conducting spherical shells $A$, $B$, and $C$ of radii $a$, $b$, and $c$ respectively. The potentials of the spheres $A$, $B$, and $C$ respectively are:

The work done to take an electron from rest where potential is $-60\, V$ to another point where potential is $-20\, V$ is given by.....$eV$.

Along the $x$-axis,three charges $\frac{q}{2}, -q$ and $\frac{q}{2}$ are placed at $x=0, x=a$ and $x=2a$ respectively. The resultant electric potential at a point $P$ located at a distance $r$ from the charge $-q$ $(r > a)$ is ($\varepsilon_0$ is the permittivity of free space):

If four charges $q_1 = +1 \times 10^{-8} \text{ C}$, $q_2 = -2 \times 10^{-8} \text{ C}$, $q_3 = +3 \times 10^{-8} \text{ C}$, and $q_4 = +2 \times 10^{-8} \text{ C}$ are kept at the four corners of a square of side $1 \text{ m}$, then the electric potential at the centre of the square is: (in $\text{ V}$)