Question

Find the expression for electric field intensity in an axial position due to electric dipole

Answer 1

The axial line of a dipole is the line passing through the positive and negative charges of the electric dipole.



Consider a system of charges (-q and +q) separated by a distance 2a. Let 'P' be any point on an axis where the field intensity is to be determined.

Electric field at P (EB) due to +q



Electric field at P due to -q (EA)



Net field at P is given by





Simplifying, we get









As a special case :



Answer 2

$\Huge\bf\purple{\mid{\overline{\underline{Answer}}}\mid}$

Electric Field Intensity :

The electric field intensity of any point is defined as the force experienced by unit positive charge placed at that point.

$\large\tt\red{E=\frac{F}{q_0}}$

The SI unit of electric field intensity

$\large \tt\orange{NC^{-1}}$

Electric field at any equatorial point of a dipole

$\large \tt{}is \: \: \: \green {\vec{E}=\frac{1}{4\pi\:\varepsilon_0}\frac{\vec{p}}{(r^2+a^2)^\frac{3}{2}}}$

At the mid-point of the dipole, r=0 so ,

$\large \tt \purple{\vec{E}=\frac{1}{4\pi\:\varepsilon_0}\frac{\vec{p}}{a^3}}$

$\huge{\mathfrak{\orange{hope\; it\; helps}}}$