I read the Coulomb's first memoir on Electricity and Magnetism (Louis L. Bucciarelli english translated version), and found it to contain only three trials (as complained by many) to reach the conclusion of a 1/r2 equation for the force. And many seems to have also complained for not having able to get the same results. I read the recent papers of A.A Martinez and others who have tried to reproduce the experiment (the technical details went beyond so I couldn't complete). What I want to know now is, what has made Coulomb's law unquestionable? Has the experimental justification for the law been given? What are the reasons for accepting it? Or is the same equation been arrived theoretically (I have a feel for this)? I have asked the same qeustion in other physics website to have faster clearance of problem.