Question

The distance of the field point, on the equatorial plane of a small electric dipole is halved. By what factor does the electric field due to the dipole change?

January 13, 2024

Answer

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

When r is halved, the electric field strength becomes 8 times the original field.

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