Kilogram
| SI multiples of gram | ||||||
|---|---|---|---|---|---|---|
| Multiple | Name | Symbol | Multiple | Name | Symbol | |
| 100 | gram | g | ||||
| 101 | decagram | dag | 10–1 | decigram | dg | |
| 102 | hectogram | hg | 10–2 | centigram | cg | |
| 103 | kilogram | kg | 10–3 | milligram | mg | |
| 106 | megagram | Mg | 10–6 | microgram | µg | |
| 109 | gigagram | Gg | 10–9 | nanogram | ng | |
| 1012 | teragram | Tg | 10–12 | picogram | pg | |
| 1015 | petagram | Pg | 10–15 | femtogram | fg | |
| 1018 | exagram | Eg | 10–18 | attogram | ag | |
| 1021 | zettagram | Zg | 10–21 | zeptogram | zg | |
| 1024 | yottagram | Yg | 10–24 | yoctogram | yg | |
The kilogram is the unit of mass in the International System of Units (SI). It is one of the seven SI base units. At the end of the 18th century, a kilogram was the mass of a cubic decimeter of water. In 1889, the 1st General Conference on Weights and Measures (CGPM) sanctioned the international prototype of the kilogram, made of platinum-iridium, and declared: This prototype shall henceforth be considered to be the unit of mass. The picture at the right shows the platinum-iridium international prototype, as kept at the International Bureau of Weights and Measures under conditions specified by the 1st CGPM in 1889.
The 3d CGPM (1901), in a declaration intended to end the ambiguity in popular usage concerning the word "weight," confirmed that:
The kilogram is the unit of mass; it is equal to the mass of the international prototype of the kilogram.
Further reading
The NIST Reference on Constants, Units, and Uncertainty| Disclaimer: This article is taken wholly from, or contains information that was originally published by, the National Institute of Standards and Technology. Topic editors and authors for the Encyclopedia of Earth may have edited its content or added new information. The use of information from the National Institute of Standards and Technology should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content. |
