Figure shows a rod ${AB}$, which is bent in a $120^{\circ}$ circular arc of radius $R$. A charge $(-Q)$ is uniformly distributed over rod ${AB}$. What is the electric field $\overrightarrow{{E}}$ at the centre of curvature ${O}$ ?
$\frac{3 \sqrt{3} {Q}}{8 \pi \varepsilon_{0} {R}^{2}}(\hat{{i}})$
$\frac{3 \sqrt{3} Q}{8 \pi^{2} \varepsilon_{0} R^{2}}(\hat{i})$
$\frac{3 \sqrt{3} Q}{16 \pi^{2} \varepsilon_{0} R^{2}}(\hat{i})$
$\frac{3 \sqrt{3} Q}{8 \pi^{2} \varepsilon_{0} R^{2}}(-\hat{i})$
Two point charges $( + Q)$ and $( - 2Q)$ are fixed on the $X-$axis at positions $a$ and $2a$ from origin respectively. At what positions on the axis, the resultant electric field is zero
Give reason : ''Small and light pieces of paper are attracted by comb run through dry hair.''
Find the electric field at point $P$ (as shown in figure) on the perpendicular bisector of a uniformly charged thin wire of length $L$ carrying a charge $Q.$ The distance of the point $P$ from the centre of the rod is $a=\frac{\sqrt{3}}{2} L$.
The distance between the two charges $25\,\mu C$ and $36\,\mu C$ is $11\,cm$ At what point on the line joining the two, the intensity will be zero
Two charges $ + 5\,\mu C$ and $ + 10\,\mu C$ are placed $20\, cm$ apart. The net electric field at the mid-Point between the two charges is