Four point charges each $+q$ are placed on the circumference of a circle of diameter $2d$ in such a way that they form a square. The potential at the centre is proportional to

Point charges $q_1 = 2\,\mu C$ and $q_2 = -1\,\mu C$ are kept at points $x = 0$ and $x = 6$ respectively. Electrical potential will be zero at points

An infinite number of charges,each equal to $0.2\,\mu C$,are arranged in a line at distances $1\,m, 2\,m, 4\,m, 8\,m, \dots$ from a fixed point. The potential at the fixed point is $......\,kV$.

If the electric potential of the inner sphere is $10\, V$ and that of the outer shell is $50\, V$,then the potential at the common centre is :- (in $, V$)

$A$ regular hexagon of side $10 \text{ cm}$ has a charge of $1 \mu\text{C}$ at each of its vertices. The potential at the centre of the hexagon is $\left[\frac{1}{4 \pi \varepsilon_0} = 9 \times 10^9 \text{ SI unit}\right]$.

Prove that electrostatic forces are conservative in nature and define electrostatic potential energy.