# The Coulombs Law

Columbs law state that the force between two small objects seperated in a vaccum by distance much greater that the size of each object is proportional to the product of charges on them and inversely proportional to square of distance between them.
$F = \frac{k Q1*Q2}{R^{2}}$
where Q1 and Q2 are positive or negative charge quantity measured in columbs and R is the distance between them measured in meters. Here k is proportionality constant given as:
$k = \frac{1}{4\pi \epsilon }$
Again another constant € is called permittivity of free space. Measured in Farad per meter(F/m).
$\epsilon _{0} = 8.854*10^{-12} = \frac{1}{36\pi }10^{-9} F/m$
The above quantity is not dimensionless. For coulombs law dimensions are C2/N.m2 . This means Farad has units C2/N.m .This makes are coulombs law as: Continue reading