Coulomb also
found 
the 
inverse
square law of force
between unlike and like
magnetic poles CHARLES AUGUSTIN DE COULOMB  (1736 –1806)
Rationalised 2023-24
8
Physics
9 × 109 N One coulomb is evidently too big a unit to
be used In practice, in electrostatics, one uses
smaller units like 1 mC or 1 mC