Information AboutTon |
|
The modern spelling ''tonne'', almost always referring to the ''metric ton'' of 1000 kilograms (or the associated obsolete force unit) when used in non-American English, is a direct borrowing from the French language. There are many meanings of ''ton'': Units of mass There are two similar units of Mass called the ton: # Long Ton (simply '''ton''' in countries such as the United Kingdom which formerly used the Imperial System of weights and measures) is a '''weight ton''' or '''gross ton''', and is 2240 lb (exactly 1016.0469088 Kg ). In the UK and most of the areas which used the Imperial system, the metric Tonne (1000 kg), which it is conveniently very similar to—less than 2% difference, is the only form of ton legal for trade.
# Short Ton (usually called simply '''ton''' in the USA or sometimes called a ''net ton'') = 2000 lb (exactly 907.18474 Kg ).
Both the long ton and the short ton are composed of twenty Hundredweight s, each having different values for the hundredweight (112 and 100 pounds respectively). Prior to the 15th Century in England , the ton was composed of twenty hundredweights, each of 108 lb, giving a ton of 2160 pounds. Assay Ton (abbreviation 'AT') is not a unit of measurement (nobody ever has ''x'' assay tons of something), but rather a standard quantity used in Assay ing ores of precious metals; it is 29 1/6 grams (short assay ton) or 32 2/3 grams (long assay ton), the amount which bears the same ratio to a milligram as a short/long ton bears to a Troy Ounce . In other words, the number of milligrams of a particular metal found in a sample of this size gives the number of troy ounces contained in a short/long ton of ore. In documents which predate 1960 the word ''ton'' may be spelt ''tonne'' however in more recent documents the spelling ''tonne'' refers exclusively to the metric Tonne . In the context of Nuclear Power Plant s, tHM and '''MTHM''' mean (metric) tonnes of Heavy Metal , and MTU means metric tonnes of Uranium . A dry ton or '''dry tonne''' has the same mass value, but the material has been dried to a relatively low, consistent moisture level. Units of force There are also the units of force based on each of these three mass units, but none are acceptable for use with SI . The metric tonne force (tonne force), like the kilogram force, is no exception. Only the metric ton or tonne as a unit of mass is acceptable for use with SI.
Units of volume Also see Tonnage . The freight ton or '''measurement ton''' is a unit of volume used for describing Ship capacities ( Tonnage ) or cargo. One measurement ton is equal to:
The measurement ton is abbreviated as M/T, MT, or MTON, which can cause it to be confused with the Metric Ton . The register ton is also a unit of volume used for the cargo capacity of a ship, defined as 100 cubic feet (roughly 2.83 cubic metres). It is often abbreviated '''GRT''' for '''gross registered ton'''. It is known as a ''tonneau de mer'' in Belgium, but, in France, a ''tonneau de mer'' is 1.44 cubic metres or about 1.88 cubic yards. The Panama Canal net ton, a unit of volume used for billing for ships going through the Panama Canal, is the same as the register ton. The fee for example in the 1990 s was roughly a couple USD for each unit. The water ton was formerly used in Great Britain and equal to 224 Imperial Gallon s (the volume occupied by a mass of one long ton under the conditions which define the imperial gallon). See 1 E-1 M³ and Orders Of Magnitude (volume) for a comparison with other volumes. (Note that volume tons are units of convenience used in shipping and are not useful in science except that they are exactly defined.) Units of energy ton of TNT
Note that these are thermal calories (not capitalized). The dietary Calorie (capitalized) is equal to one thousand thermal calories. Early values for the explosive energy released by Trinitrotoluene (TNT) ranged from 900 to 1100 calories per gram. In order to standardise the use of the term ''TNT'' as a unit of energy, an arbitrary value was assigned based on 1000 calories (4.184 kilo Joules ) per gram. Thus there is no longer a direct connection to the chemical TNT itself. It is now merely a unit of energy that happens to be expressed using words normally associated with mass (e.g. kilogram, tonne, pound) (IAEA references: [http://www.iaea.org/Publications/Magazines/Bulletin/Bull404/article1.pdf ). The definition applies for both spellings: ''ton of TNT'' and ''tonne of TNT''. Measurements in tons of TNT have been used primarily to express Nuclear Weapon Yield s, though they have also been used since in Seismology as well. Sample terms: ton of coal equivalent
ton of oil equivalent
Unit of power
Miscellaneous tons
Tonnin' (Tonning)Vb: To travel long distances (motorways) at 100mph in a mechanically propelled vehicle. e.g. "He\She is tonnin' back to the capital" See also
|