Question

Write the expression for electric intensity at a point due to point charge and explain the terms.

Answer 1

Electric Intensity due to a point charge:-

$F=E{q}_0$ [force experienced by the charge $q_0$]

$F=\frac{kq{q}_0}{r^2}$ [according to collomb's law]

$r=$ distance between the $q$ and $q_0$ source charge

we know, $E=\frac{F}{q_0}$

$E=\frac{1}{q_0}\times \frac{kq{q}_0}{r^2}$

$E=\frac{kq}{r^2}$ we know $k=\frac{1}{4\pi {\in }_0}$

Final Expression $\to E=\frac{1}{4\pi {\in }_0}\times \frac{q}{r^2}$

${\in }_0=$ dielectric constant of letan $k$ space

$q=$ point charge

$r=distance between two point charge

If there is a medium of dielectric constant ${\in }_r$ then,

$E=\frac{1}{4\pi {\in }_0{\in }_r}.\frac{q}{r^2}$

Vector from $\to \overrightarrow{E}=\frac{1}{4\pi {\in }_0{\in }_r}.\frac{q}{r^2}.\overrightarrow{r}$