Early life. Ferdinand Magellan was born about 1480 to a noble family in Portugal. As a boy, he served the queen of Portugal as a page, and studied cartography and navigation tenaciously.
There are seven fundamental units: the metre, kilogram, second, ampere, kelvin, candela, and mole; and two supplementary units: the radian and the steradian. All other units are derived by multiplication or division of these units without the use of numerical factors. SI units in Medicine Expand. International System of Units n. Abbr. SI. A complete, coherent system of units used for scientific work, in which the fundamental quantities are length, time, electric current, temperature, mass, luminous intensity, and amount of substance. Also called International System. SI unit. Any of the units of measure in the International System.
The International System of Units (SI), commonly known as the metric system, is the international standard for measurement. The International Treaty of the Meter was signed in Paris on May 20, 1875 by seventeen countries, including the United States and is now celebrated around the globe as World Metrology Day.he SI is made up of 7 base units that define the 22 derived units with special names and symbols. The international prototype of the kilogram is the only remaining artifact used to define a base unit of the SI (rather than definition by a fundamental constant).