ancient egypt atomic physics atomic units avoirdupois british empire canadian units centimetre gram second system of units chinese units of measurement commonwealth of nations conversion of units cubit dimension dimensional analysis dutch units of measurement elam electric field elephant ell engineering fathom finnish units of measurement france french units of measurement fundamental unit geometrized unit system german units of measurement gravitational metric system hindu units of measurement hiroshima history of measurement history of measurement systems in india indus valley civilization international system of units iran japanese units of measurement korean air leonardo da vinci list of humorous units of measurement list of unusual units of measurement magnetic field maltese units of measurement mars climate orbiter measurement medicine mesopotamia mesures usuelles metre-tonne-second system of units metric system metrication metrology nasa natural units newton norwegian units of measurement obsolete scottish units of measurement orbit pegu weights and measures persian units of measurement physical quantity physics planck units planet problem solving quantity reproducibility romanian units of measurement si base unit si derived unit science scientific method seoul shanghai social sciences solar mass standardization surface tension swedish units of measurement systems of measurement taiwanese units of measurement trinitrotoluene troy weight united states united states customary units units conversion by factor-label vitruvian man weights and measures act yard