The electric field inside a spherical shell of uniform surface charge density 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

$A$ spherically symmetric charge distribution is considered with charge density varying as
$\rho(r)=\begin{cases} \rho_{0}\left(\frac{3}{4}-\frac{r}{R}\right) & \text{for } r \leq R \\ 0 & \text{for } r>R \end{cases}$
Where,$r (r < R)$ is the distance from the centre $O$ (as shown in figure). The electric field at point $P$ will be.

An infinite line charge produces a field of $9 \times 10^4 \; N/C$ at a distance of $2 \; cm$. Calculate the linear charge density in $\mu C/m$.

$A$ force of $10 \; N$ acts on a charged particle placed between two plates of a charged capacitor. If one plate of the capacitor is removed,then the force acting on that particle will be ...... $N$.

Let $\sigma$ be the uniform surface charge density of two infinite thin plane sheets shown in the figure. Then the electric fields in three different regions $I, II$ and $III$ are: