alþjóðakerfinu

Alþjóðakerfinu, also known as the International System of Units (SI), is the modern form of the metric system and is the most widely used system of measurement in the world today. It comprises a coherent system of units of measurement built on seven base units, which are the second, metre, kilogram, ampere, kelvin, mole, and candela. These base units are used to derive 22 coherent derived units, such as the volt, watt, and newton.

The SI was established by the General Conference on Weights and Measures (CGPM) in 1960, and its definitions are periodically reviewed and updated. The SI is maintained by the International Bureau of Weights and Measures (BIPM), located in Sèvres, France. It is used in science, engineering, industry, and everyday life.

The SI is based on the principles of coherence and traceability. Coherence means that the units are defined in such a way that they are consistent with each other, and traceability means that the units can be traced back to the definitions of the base units. This ensures that measurements are accurate, reliable, and comparable.

The SI is continually evolving to meet the needs of science and technology. New units are added as needed, and the definitions of existing units are updated to reflect advances in measurement science. The SI is a vital tool for international trade, science, and technology, and its use is essential for ensuring the accuracy and reliability of measurements worldwide.