A ton(ne) (symbol t) is a unit of mass. It is not an SI unit but is accepted for use with the SI. The SI unit of mass is the kilogram and a tonne is correctly described in SI as a megagram. Mass is a property of physical objects that, roughly speaking, measures the amount of matter they contain. ... The International System of Units (abbreviated SI from the French language name Système International dUnités) is the most widely used system of units. ... The international prototype, made of platinum-iridium, which is kept at the BIPM under conditions specified by the 1st CGPM in 1889. ...

Definition

1 t = 1000 kg

Multiples

Origin

The spelling tonne is from French. In old English the spelling was tunne. The various spellings and meanings (tonne, ton, tun) derive from late latin tunna (cask). It may be of celtic origin. A full cask about a metre high could easily weigh 1 tonne.

Conversions

One tonne is equivalent to:

• 1 megagram (exactly). Symbol Mg. This is the SI term
• 2204.62262 pounds

Explanation

The official symbol is t, but T and mT and mt (especially in the combination mmt for "million metric tons") are also used.

In France and the English-speaking countries that are predominately metric, the spelling tonne is widespread. However, in Britain, the common people consider that its measure is very close to that of the long ton and often don't bother with the distinctive spelling; for example, even the Guiness Book of World Records accepts metrification without marking this by changing the spelling. For the United States, metric ton is the name for this unit used and recommended by NIST. [1] A long ton is the name used in the US for the unit called the ton in the avoirdupois or Imperial system of measurements, as used (alongside the metric system) in the United Kingdom and to some extent in other Commonwealth countries. ... The Guinness Book of Records (or in recent editions Guinness World Records, and in previous US editions Guinness Book of World Records) is a book published annually, containing an internationally recognized collection of superlatives: both in terms of human achievement and the extrema of the natural world. ... Metrication, or metrification, is the process of converting from the various other systems of units used throughout the world (especially the Imperial or American systems, originating in the United Kingdom) to the metric or SI (Système International) system. ...

Like grams and kilograms, tonnes have also given rise to a force unit of the same name: 1 tonne-force = 9.80665 kilonewtons (kN), a unit also often called simply "tonne" or "metric ton" without identifying it as a unit of force. Note that it is only the tonne as a unit of mass which is accepted for use with SI; the tonne-force or metric ton-force is not acceptable for use with SI. The newton (symbol: N) is the SI unit of force. ...

The ton of TNT or tonne of Trinitrotoluene is a unit of energy with the tonne as a proxy term. This unit is not acceptable for use with SI. Assuming 1000 small (thermochemical) calories per gram (4.184 kJ/g) and thus a tonne of TNT is 4.184 GJ. A megaton or megatonne is a unit of mass equal to 1,000,000 metric tons, i. ... Trinitrotoluene (TNT, or Trotyl) is a pale yellow crystalline aromatic hydrocarbon compound that melts at 354 K (178 Â°F, 81 °C). ... A calorie (cal) is a unit of measurement for energy. ... The joule (symbol: J) is the SI unit of energy, or work. ...

See also

• Units using the tonne
  • ton of oil equivalent
  • GTOE
• Other tons
  • short ton
  • long ton
  • tonnage
  • ton (volume)
• Conversion of units

The ton of oil equivalent (TOE) is a unit for measuring energy. ... Gtoe is an abbreviation for giga tonne oil equivalent, a common measure of global energy. ... The word ton or tonne is derived from the Old English tunne, and ultimately from the Old French tonne, and referred originally to a large cask with a capacity of 252 wine gallons, which holds approximately 2100 pounds of water. ... The short ton is a unit of mass equal to 907. ... A long ton is the name used in the US for the unit called the ton in the avoirdupois or Imperial system of measurements, as used (alongside the metric system) in the United Kingdom and to some extent in other Commonwealth countries. ... Tonnage is a measure of the size or cargo capacity of a ship. ... For ton as a unit of mass, see ton The freight ton or measurement ton is a unit of volume used for describing ship capacities (tonnage) or cargo. ... This article lists conversion factors between a number of units of measurement. ...

References

• NIST Special Publication 811, Guide for the Use of the International System of Units (SI)