The exponent in the Coulomb's inverse quare law has been found to differ from two by less than one part in a billion by measuring which of the following?
(A) the charge on an oil drop in the Millikan experient
(B) the deflection of an electron beam in an electric field
(C) the neutrality of charge of an atom
(D) the electric force betweem two charged objects
(E) the electric field inside a charged conducting shell
后面附的解答为:如果Coulomb平方反比定律严格成立,则可以用Gauss定理证明在均匀带电球壳内部电场处处为零。