Talk:Tonne
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[edit] word origins
- The naming of this unit was far from original because SI advocates derived the name of their unit from the already well established ton and added an '-ne' suffix to differentiate between the SI tonne and non-metric ton. The tonne is also less formally called metric ton but this name is deprecated since it mixes metric and non-metric terms.
This wasn't done by "SI advocates"; the names ton and tonne existed long before there was an SI, which was only introduced in 1960.
It wasn't the adding of an -ne to the English word for this distinguishing purpose. Rather, it was a direct borrowing of the French word. A French word which dates back to even before there was any metric system, let alone the modern version called the International System of Units.
In French, of course, "tonne" is just as ambiguous as "ton" is in English. What do you suppose an unidentified "tonne" would have been in Quebec 50 years ago, for example? Most likely a tonne courte, or 2000 English pounds, unless it was in shipping where it would likely be the tonne forte of 2240 lb.
I'm no expert in French, but I think it would be a pretty safe assumption that today (though not necessarily in the past), wherever French is spoken or written, if tonne is used without any other identifying adjective, it is the tonne mètrique.
In English, "tonne" is somewhat less ambiguous than in French. Nonetheless, the terms "short tonne" and "long tonne" are used, rarely. Furthermore, many are careful to specifically identify the units as "metric tonnes"; Google
"metric tonne" 37,200 hits
"metric tonnes" 149,000 hits
Gene Nygaard 14:09, 16 Dec 2004 (UTC)
- To complicate matters, the French « tonne » also designates a large liquid container (of which the barrel, « tonneau » is a diminutive), more or less the equivalent of the English tun.
- Urhixidur 11:25, 2005 Jun 23 (UTC)
[edit] TNT
"ton of TNT or tonne of Trinitrotoluene is a unit of energy based on the tonne, assuming 1000 small (thermochemical) calories per gram (4.184 kJ/g) and thus a tonne of TNT is 4.184 GJ. This unit is also not acceptable for use with SI."
This argument is pretty much meaningless, because those who speak (kilo)ton TNT have the nukes and so they don't need to care a damn about SI or customary units. It's hard to argue with someone who has the bomb ...
- i've seen not acceptable for use with SI in various places on wikipedia. I suspect "acceptable for use with SI" has a specific technical and/or regulatory meaning can anyone confirm?
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- There are three or four different classes of units which are acceptable for SI; some of those units are only "currently" (BIPM) or "temporarily" (NIST) acceptable.
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- Gene Nygaard 10:04, 23 Jun 2005 (UTC)
[edit] weight/mass
surely the tonne is a measurement of mass and not weight as is stated in the first line of the wiki entry ?
