Question

For a short dipole, the ratio of the electric field on the axial line to that on the equatorial line (at the same distance r) is:

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Answer 1

The electric field on the axial line is \[E_{axial} = \frac{2p}{4\pi\varepsilon_0 r^3}\], while on the equatorial line it is \[E_{eq} = \frac{p}{4\pi\varepsilon_0 r^3}\]. Therefore, the ratio is \[E_{axial} = 2E_{eq}\], which means the axial field is twice as strong as the equatorial field at the same distance from the dipole.