Question

In Coulomb's law, the constant of proportionality K has the units?
1.N
2.Nm²
3.NC²/m²
4.Nm²/C²​

Answer 1

$\bold {\huge {Answer :-}}$

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Since, force between two charged particles is given by

$\bf\huge\boxed{F=\frac{K×q_1×q_2}{r^2}}$

K is the proportionality constant

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By arranging them

$\bf\huge\boxed{K=</p><p>\frac{F×r^2}{q_1×q_2}}$

$\\\\\:we\:know\:that, \\\\1.unit\:of\:Force(F)→Newton(N) \\2.unit\:of\:radius(r)→meters (m) \\3.unit\:of\:charge→columb (C)$

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➛Therefore unit of proportionality constant (K)

$= \frac{(N \times m^{2} )}{columb^{2} } = \frac{Nm^{2} }{C^{2} }$

Option→(4)