The electric field at a point on the equatorial plane at a distance r from the centre of a dipole having dipole moment $\vec{p}$ is given by, (r >> separation of two charges forming the dipole, $\varepsilon_0$ - permittivity of free space)

A $\vec{E}=\dfrac{-\vec{p}}{4\pi\varepsilon_0 r^3}$

B $\vec{E}=\dfrac{\vec{p}}{4\pi\varepsilon_0 r^3}$

C $\vec{E}=\dfrac{-2\vec{p}}{4\pi\varepsilon_0 r^3}$

D $\vec{E}=\dfrac{\vec{p}}{4\pi\varepsilon_0 r^2}$

The answer is A.

Solution

The electric field at an equatorial point of a dipole, for $r\gg$ charge separation, is $\vec{E}=\dfrac{-\vec{p}}{4\pi\varepsilon_0 r^3}$ (directed opposite to the dipole moment).

Concept Electric field due to a dipole on the equatorial line

Electric Charges and Fields in past papers

42 questions from this chapter have appeared across 23 exam years.

The electric field at a point on the equatorial plane at a distance r from the centre of a dipole having dipole moment $\vec{p}$ is given by, (r >> separation of two charges forming the dipole, $\varepsilon_0$ - permittivity of free space)

Solution

Electric Charges and Fields in past papers

Practice

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