A charge $( - q)$ and another charge $( + Q)$ are kept at two points $A$ and $B$ respectively. Keeping the charge $( + Q)$ fixed at $B$, the charge $( - q)$ at $A$ is moved to another point $C$ such that $ABC$ forms an equilateral triangle of side $l$. The net work done in moving the charge $( - q)$ is
$\frac{1}{{4\pi {\varepsilon _0}}}\frac{{Qq}}{l}$
$\frac{1}{{4\pi {\varepsilon _0}}}\frac{{Qq}}{{{l^2}}}$
$\frac{1}{{4\pi {\varepsilon _0}}}Qql$
Zero
A block of mass $m$ moving with speed $v$ compresses a spring through distance $x$ before its speed is halved. What is the value of spring constant ?
Distinguish difference between electric potential and electric potential energy
Two identical thin rings each of radius $R$ meters are coaxially placed at a distance $R$ meters apart. If $Q_1$ coulomb and $Q_2$ coulomb are respectively the charges uniformly spread on the two rings, the work done in moving a charge $q$ from the centre of one ring to that of other is
There exists a uniform electric field $E=4 \times 10^5 \,Vm ^{-1}$ directed along negative $x$-axis such that electric potential at origin is zero. Acharge of $-200 \,\mu C$ is placed at origin, and a charge of $+200 \,\mu C$ is placed at $(3 \,m , 0)$. The electrostatic potential energy of the system is ...........$J$
If $4 \times {10^{20}}eV$ energy is required to move a charge of $0.25$ coulomb between two points. Then what will be the potential difference between them......$V$