Using Gauss's law determine the intensity of electric field at a point near a uniformly charged infinite wire. Graph the variation of electric field with distance.

In the figure $\left(a\right)$ an electron is shot directly away from a uniformly charged plastic sheet, at speed $v_{\mathrm{s}}$. The sheet is nonconducting, flat, and very large.

$\left(b\right)$ gives the electron's vertical velocity component versus time $t$ until the return to the launch point. What is the sheet's surface charge density?

The figure $\left(a\right)$ shows three plastic sheets that are large, parallel, and uniformly charged.

The figure $\left(b\right)$ gives the component of the net electric field along an $x‐$axis through the sheets. The scale of the vertical axis is set by $E_{\mathrm{S}}=6.0\times {10}^5 \mathrm{N} {\mathrm{C}}^{-1}$. What is the ratio of the charge density on the sheet $3$ to that on the sheet $2$?

For a spherical conductor of radius $R$ having a charge $q$ determine electric field for following situations:

(A) $r<R$

(B) $r>R$

(C) at its surface

(D) at its centre

Graph the variation of electric field with distance.