Three infinitely long charge sheets are placed as shown in figure. The electric field at point $P$ is
$\frac{{2\sigma }}{{{\varepsilon _o}}}$$\hat k$
$ - \frac{{2\sigma }}{{{\varepsilon _o}}}$$\hat k$
$\frac{{4\sigma }}{{{\varepsilon _o}}}$$\hat k$
$ - \frac{{4\sigma }}{{{\varepsilon _o}}}$$\hat k$
A conducting sphere of radius $10\, cm$ has unknown charge. If the electric field at a distance $20\, cm$ from the centre of the sphere is $1.2 \times 10^3\, N\, C^{-1}$ and points radially inwards. The net charge on the sphere is
An infinitely long positively charged straight thread has a linear charge density $\lambda \mathrm{Cm}^{-1}$. An electron revolves along a circular path having axis along the length of the wire. The graph that correctly represents the variation of the kinetic energy of electron as a function of radius of circular path from the wire is :
Two infinitely long parallel conducting plates having surface charge densities $ + \sigma $ and $ - \sigma $ respectively, are separated by a small distance. The medium between the plates is vacuum. If ${\varepsilon _0}$ is the dielectric permittivity of vacuum, then the electric field in the region between the plates is
If the total charge enclosed by a surface is zero, does it imply that the electric field everywhere on the surface is zero ? Conversely, if the electric field everywhere on a surface is zero, does it imply that net charge inside is zero.
Two parallel infinite line charges with linear charge densities $+\lambda\; \mathrm{C} / \mathrm{m}$ and $-\lambda\; \mathrm{C} / \mathrm{m}$ are placed at a distance of $2 \mathrm{R}$ in free space. What is the electric field mid-way between the two line charges?