When a charge of $20 C$ is taken from one point to another separated by a distance of $0.2 m$,work of $2 J$ is required to be done. What is the potential difference between the two points?

$m$ દળ અને $q$ વિદ્યુતભાર ધરાવતી એક ગોળીને $R$ ત્રિજ્યા અને કુલ $+q$ વિદ્યુતભાર ધરાવતા સમાન રીતે વિદ્યુતભારીત નક્કર ગોળા તરફ છોડવામાં આવે છે. જો તે $u$ ઝડપ સાથે ગોળાની સપાટી પર અથડાય,તો ગોળામાંથી પસાર થવા માટે જરૂરી લઘુત્તમ ઝડપ $u$ શોધો. (સ્થિત વિદ્યુત બળો સિવાય ગોળી પર લાગતા તમામ અવરોધક બળો અથવા ઘર્ષણને અવગણો.)

Two charges $+q$ and $-q$ are placed at points $A$ and $B$ respectively, which are at a distance $2L$ apart. $C$ is the midpoint of $A$ and $B$. The work done in moving a charge $+Q$ along the semicircle $CSD$ $(W_1)$ and along the line $CBD$ $(W_2)$ are:

The electrostatic potential on the surface of a uniformly charged spherical shell of radius $R = 10 \ cm$ is $120 \ V$. The potential at the centre of the shell,at a distance $r = 5 \ cm$ from the centre,and at a distance $r = 15 \ cm$ from the centre of the shell respectively,are:

Three particles,each having a charge of $10\,\mu C$,are placed at the corners of an equilateral triangle of side $10\,cm$. The electrostatic potential energy of the system is.....$J$ (Given $\frac{1}{4\pi\varepsilon_0} = 9 \times 10^9\,N\cdot m^2/C^2$).

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