Question

in coulombs law the constant of proportionality K has the units ?

Answer 1

we know that according to coulombs law the force of attraction or repulsion between electric charges is given by F = (K × q₁ × q₂)/r²

making K as the subject we get K = (F × r²)/q₁q₂

we know that force is expressed in newtons and r in meters and charges in coulombs

⇒ substituting these values in the above equation we get

K =( Newton × meter² )coulomb²

⇒ units of K = (N×m²)/C²