The coulomb (symbol: C)'s the SI derived unit of electric charge. It's named after Charles-Augustin de Coulomb. Definition One coulomb's the amount of electric charge transported in one second by a steady current of one ampere. » 1 mathrm Explanation In principle, the coulomb could be defined in terms of the charge of an electron or elementary charge. Since the values of the Josephson (CIPM (1988) Recommendation 1, PV 56; 19) and von Klitzing (CIPM (1988), Recommendation 2, PV 56; 20) consta… (More on Coulomb)