Two charges of magnitude $+q$ and $-3q$ are placed $100 \, cm$ apart. The distance from $+q$ between the charges where the electrostatic potential is zero is ....... $cm$.

$A$ thin conducting spherical shell of radius $R$ has a charge $q$. Another charge $Q$ is placed at the center of the shell. The electrostatic potential at a point $P$ at a distance $R/2$ from the center of the shell is:

Do free electrons travel to a region of higher potential or lower potential?

The potential difference $(V_A-V_B)$ in the arrangement shown in the figure is $(q=1 \mu C, x=2 \text{ cm}, y=3 \text{ cm})$.

The side length of an equilateral triangle is $d$. Three charges,each of magnitude $Q$,are placed at the three vertices. If $P$ is the midpoint of one side,find the electric potential $V_P$ at point $P$.

The figure shows a charge array known as an electric quadrupole. For a point on the axis of the quadrupole,obtain the dependence of potential on $r$ for $r / a >> 1,$ and contrast your results with that due to an electric dipole,and an electric monopole (i.e.,a single charge).