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प्रश्न
Write down Coulomb’s law in vector form and mention what each term represents.
उत्तर
The force on the point charge q2 exerted by another point charge q1
`vec"F"_21 = ("K""q"_1"q"_2)/"r"^2 hat"r"_12`
where `hat"r"_2` is the unit vector directed from charge q1 to charge q2, and ‘K’ is the proportionality constant K = `1/(4 pi ε_0)`; ε0 is the permittivity of free space.
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