Dear student,

Please post the question that you want the answer for.

As you know the Coloumb''s inverse square law states that "The force of attraction or repelling between the two charges is directly proportional to the mass of the two charge particles and it is inversely proportional to the square of distance between them."

                             1.  F proportional to m1 X m2

                             2. F inversely proportional to r^2

Filnally we got the expression as 

                                        m1 X m2

                                  F= -----------------

                                           r^2

f=q1q2/r^2...cloumbs force