Question

The distance of the field point on the axis of a small dipole is doubled. By what factor will the electric field, due to the dipole change?

January 13, 2024

Answer

For small dipole, E_axis= ${1\over 4 \pi\varepsilon_0}{p\over r^3} \propto {1\over r^3}$

When the distance r is doubled, the electric field strength becomes 1/8 times the original field.

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