Talk:Tonne

message: "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?
::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.
::*BIPM SI brochure
::*NIST Special Publication 811
:: Gene Nygaard 10:04, 23 Jun 2005 (UTC)
thread_title:  TNT 

message: From the article:
:The proper SI unit for a tonne would be a "kilokilogram" (the kilogram is the basic unit, not the gram), but this term is never used in practice.
This sounds fishy to me. A gram is a gram, not a "millikilogram", and a milligram is a milligram, not a "microkilogram". Unless a reliable source is given for this sentence, I'm going to delete it soon. —Bkell (talk) 13:06, 9 May 2007 (UTC)
replies: text: Okay, I'm going to change "kilokilogram" back to "megagram" (in effect undoing this edit). "Kilokilogram" was added by an anonymous user with no justification or sources cited. —Bkell (talk) 13:09, 9 May 2007 (UTC)
replies: text: As I recall, the anonymous user was me. I must have forgotten to sign in. The kilogram is still the basic unit of mass in the SI system (see any book on physics). I'm changing it back. The confusion arises, of course, because the kilogram alone of all the basic units, has a prefix. Cheers Io 17:44, 16 May 2007 (UTC)
replies: text: On second thoughts, let it stand. It is adequately explained as 1000 kilograms in the article. But a megagram is definitely not a standard word for any amount of mass. Whoever wrote the original article was probably confusing the SI with the cgs-system. As for references, let's see: Will the Handbook of Physics by Benenson, Harris, Stöcker and Lutz, Springer 2002, page 1125, translated from the 4. ed. of Taschenbuch der Physik, edited by Horst Stöcker do? Cheers Io 17:53, 16 May 2007 (UTC)
replies: text: I can't say i've ever seen either megagram or kilokilogram used before but doubling up prefixes certainly seems stranger to me than the unusual prefix-unit combination of megagram. As Bkell said we don't call a gram a milikilogram or call a milligram a microkilogram. One physics textbook does not standard terminology make. Unless the SI standard has something explicit to say about this or there is evidence of widespread usage of one or both of the terms I don't think either should be mentioned in this article. Plugwash 00:05, 25 June 2007 (UTC)

text: Ok i've just checked the SI site and it clearly states that names for mass units should be made by applying prefixes to gram to to kilogram. Plugwash 00:34, 25 June 2007 (UTC)

text:  Megagram(me) or Mg, see SI prefix, would be quite acceptable but so is tonne (t). The latter for convenience's sake. Peter Horn 20:14, 16 August 2007 (UTC)
replies: text: Actually there could be conflict over Tonne and Metric Ton. Megagram(me) or even Mg instead.SirChan (talk) 02:22, 31 March 2008 (UTC)
thread_title:  "Kilokilogram" 

message: Though the spelling tonne predates the introduction of the SI system in 1960, it is now used as the standard spelling for the metric mass measurement in English. 
What an odd sentence. Why should the SI system have any bearing on language spelling? The sentence almost implies to me that the author was expecting the spelling of the word to be redefined by some sort of committee on weights and measures. Why not write this ....?
The spelling tonne predates the introduction of the SI system in 1960, and is now used as the standard spelling for the metric mass measurement in English. 
Crysta1c1ear 17:03, 24 June 2007 (UTC)
replies: text: This sentence ignores NIST's (U.S.A.) preference for "Metric Ton." It should be modified to describe it's use in non-U.S. English at least. SirChan (talk) 02:27, 31 March 2008 (UTC)
thread_title:  "Spelling" 

message: I believe that the article has approached the subject backwards. It primarily describes this unit as a tonne (along with the title) while leaving the metric ton and megagram as footnotes (which redirects to tonne). It should be addressed as a megagram and then mentioning the colloquial use of the tonne and metric ton in order to be free from (allegations of) cultural bias.SirChan (talk) 21:00, 7 April 2008 (UTC)
replies: text: I agree, but for a different reason. A person who has taken the trouble to learn what gram means and what mega- means should be allowed to make use of that knowledge by always referring to masses in the vicinty of the mass of an automobile with the word megagram. Forcing a person to learn yet another strange unit (tonne) places an unfair burden on readers. --Gerry Ashton (talk) 23:58, 23 April 2008 (UTC)

text: I agree also. If there's no other indication, should we start a megagram page with this one linked to it or should it be instead this page moved to megagram with subsections for tonnes?
--Cpt ricard (talk) 15:07, 9 September 2014 (UTC)
thread_title:  Wrong approach 

message: * What did you do to the this article with this series of edits. Here’s what the article used to look like before you ripped out the SI prefixes. The BIPM in their CIPM, 1967: Recommendation 2 didn’t say the SI prefixes can’t be used with tonne. In fact, they didn’t say anything about the tonne. Recommendation 2 was clearly addressing the issue that you attach SI prefixes to the gram and not the kilogram. Further, SI brochure, Table 6 (Section 4.1) (“Non-SI units accepted for use with the SI, and units based on fundamental constants”) specifically includes the tonne—along with the liter—among the non-SI units that are acceptable for use with the SI. That means with the SI prefixes too. As you no doubt know (or should know), prefixed forms of the liter (one of the other non-SI units that are acceptable for use with the SI) are perfectly well accepted throughout the world (see Litre#SI prefixes applied to the litre. Are you going to go and delete the SI table from the Liter article too? In fact, the BIPM, in their French language Réglementation Métrologique (1970) (103 KB download, here) specifically acknowledges that the prefixed forms of tonne are “becoming recognized.” And that was back in 1970! You need to settle down and familiarize yourself with the world of the SI before performing such radical changes. Greg L (talk) 03:36, 24 April 2008 (UTC)
thread_title: SI prefixes and the tonne

message: In the USA this unit was defined in 1866[3] as a millier or a tonneau (both French words). This measure was used in Europe centuries earlier.  - since the metric system didn't exist "centuries earlier" than 1866, what were these words used to refer to? --Random832 (contribs) 03:55, 4 July 2008 (UTC)
thread_title:  Millier/tonneau 

message: Googling for (Femtotonne -attotonne -"The symbol ft is shared with that for") gives no results. Therefore I've removed the reference. Rich Farmbrough, 19:25 15 July 2008 (GMT).
: I vaguely remember adding that remark, probably because I noticed the symbol ft used for femtotonne in the table and found it confusing. I don't feel strongly about it, but I don't see any harm in pointing out the ambiguity to the reader. Thunderbird2 (talk) 12:57, 20 July 2008 (UTC)
thread_title: Femottonne

message: This is so close to the tonne that many people draw little distinction and continue to use the old spelling.--Filll (talk | wpc) 12:48, 20 July 2008 (UTC)
thread_title:  Confusing sentence 

message: Does MT refer to tonne? in here should it be interpreted like metric tonne or mega tonne? Will 11:59, 26 September 2008 (UTC)
replies: text: According to the "technical notes" link on that page (bottom left) MT means metric ton. Apparently that organization has decided to completely ignore international standards about when to use upper and lower case letters. --Gerry Ashton (talk) 15:38, 26 September 2008 (UTC)

text: In a practical sense, seeing use of "MT" in the wild gives it meaning, and should be represented in wiki, if only to reduce confusion and help to sell the use of proper units. Indeed, I'm writing this today because saw a vendor offering annual production of 35,000MT of bulk solids, and I needed to know if these were meant as mega- or metric- tons. I'm going with the latter, simply because "megaton" in another vernacular refers to the explosive yield of ICBMs. (And of course MT is also properly used for Megateslas...)--204.44.137.252 (talk) 18:20, 8 March 2021 (UTC)
thread_title:  MT 

message: Kiloton and Megaton go to TNT equivalent. Gigaton goes to Tonne.
Teraton, Petaton, and Exaton all have tiny stubs.  These should probably all point to the same place, but which article?
--Suffusion of Yellow (talk) 01:04, 18 October 2009 (UTC)
replies: text: Possibly all could redirect to Tonne, and we could have a hatnote mentioning TNT equivalent.  I think tonne always refers to 1000 kg, but word usage sometimes talks about kilotons to mean TNT, without explicitly stating it.  —fudoreaper (talk) 00:06, 20 October 2009 (UTC)
replies: text: These units are used virtually exclusively for TNT equivalent, or not at all (exaton), so this is the more suitable redirect. I think the stubs should be redirects, maybe to Kiloton or TNT equivalent. Pol098 (talk) 13:22, 8 March 2012 (UTC)
thread_title:  Inconsistent redirects 

message: "Ton" and "tonne" may be pronounced identically in some countries, but from where I come (Australia) we have been taught that there is a difference in pronunciation between the two words.  My second edition of Macquarie Dictionary gives the phonetic spelling of "tonne" with a short "o" sound, meaning tonne rhymes with "john".  The latest version of Macquarie Dictionary online also uses this pronunciation.  This probably should be pointed out in the article. Wcp07 (talk) 05:35, 17 July 2011 (UTC)
replies: text: If this is general usage, it could be added to the article. Pol098 (talk) 18:17, 8 March 2012 (UTC)
replies: text:  In UK, I've heard "tonne" pronounced as "tunny" by chemical engineers to distinguish the metric unit from the long ton. Otherwise, "tonne" is pronounced exactly the same as "ton" (i.e like "tun"). Can anyone find something WP:RS for this? Narky Blert (talk) 23:49, 4 August 2017 (UTC)

text:  It *is* general usage in Australia. The pronunciation was recommended by the Metric Conversion Board when Australia metricated in the 1970s. I have added a citation to the article. Paul Foxworthy (talk) 22:53, 31 October 2021 (UTC)
thread_title:  Pronunciation 

message: Current text - "For multiples of the tonne, it is more usual to speak of thousands or millions of tonnes. Kilotonne, megatonne, and gigatonne are more usually used for the energy of nuclear explosions and other events, often loosely as approximate figures."
Gt and Mt are used routinely to describe units of carbon dioxide (GtCO2), e.g. in IPCC texts, country statements to UNFCCC and so on. Pg (rather than Gt) is often used to describe units of carbon (in journal papers).
So it is odd to see these units being dismissed as only used to measure energy.  — Preceding unsigned comment added by Flit (talk • contribs) 21:14, 17 October 2015 (UTC)
thread_title:  Missing some usages 

message: I think that the current lead section text
* " or 0.984 tons (imperial)"
should be changed to something like
* " or 0.984 long tons (imperial)" or
* " or 0.984 imperial/long tons",
for the following reasons:
* The corresponding article titles are Short ton and Long ton.
* We should give as much context as possible, i.e. short=US, long=imperial.
* Citing from Short ton: "In order to avoid confusion, especially in international environments, it is recommended to always use the full name: "short ton", "long ton" or "metric tonne"." According to my knowledge, Wikipedia is an international environment.
* The text in parentheses does not appear in hovercards, so if we hide the words "short" and "long", the hovercard shows just "1.10 tons or 0.984 tons", which is confusing.
 Your reversion summary seems to assume that enwiki is just for US/UK readers - I think that it isn't. Petr Matas 16:49, 7 December 2015 (UTC)
thread_title:  "Short" and "Long" ton should appear in the lead section 

message: Programme
Personne (not used in English spelling)
Gramme
Steppe (rare form of step)
Matte (rare form of mat)  — Preceding unsigned comment added by 124.106.142.94 (talk) 03:51, 24 April 2016 (UTC)
replies: text: strut, bud, dull, gun. See Help:IPA for English, and the very start of the article. --Nigelj (talk) 09:59, 24 April 2016 (UTC)

text: Ton. - BilCat (talk) 10:05, 24 April 2016 (UTC)
replies: text:  In UK - bun, dun, fun, gun, Hun, nun, pun, run, spun, stun, sun, ton, tun, won. I may have missed some. Narky Blert (talk) 23:53, 4 August 2017 (UTC)
replies: text: Ah, so you actually pronounce it with "ah"; while Russians pronounce their word, "tonna" with "oh"... that's confusing... Uchyot (talk) 08:24, 16 March 2021 (UTC)
thread_title:  What rhymes with tonne? 

message: Hello fellow Wikipedians,
I have just modified 2 external links on Tonne. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
*Added archive https://web.archive.org/web/20091001100650/http://www.bipm.org/en/si/si_brochure/chapter4/table6.html to http://www.bipm.org/en/si/si_brochure/chapter4/table6.html
*Added archive http://webarchive.nationalarchives.gov.uk/20110207120946/http://www.nmo.bis.gov.uk/Docs/Legislation/Units%20of%20Measurement/Gnotes%20for%20public%20sector%20on%20use%20of%20metric.pdf to http://www.nmo.bis.gov.uk/Docs/Legislation/Units%20of%20Measurement/Gnotes%20for%20public%20sector%20on%20use%20of%20metric.pdf
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thread_title:  External links modified 

message: Since the density of water changes with temperature, perhaps it would be helpful to say at which temperature the mass of one tonne is identical to that of one cubic meter of water. — Preceding unsigned comment added by 165.166.59.134 (talk • contribs) 11:32, 25 July 2019 (UTC)
replies: text: True. If you knew what temperature it is you could have changed it. I'll see if I can find it anywhere. JBW (talk) Formerly known as JamesBWatson 20:53, 23 September 2019 (UTC)

text: It turns out it is at 4°C, so I'll put that in the article. JBW (talk) Formerly known as JamesBWatson 09:05, 24 September 2019 (UTC)
thread_title: Temperature Dependence

message: I don't really like the article's "concreete block" picture. It's gloomy "greenish grey/gray", like boring concrete structure after rain always is. Uchyot (talk) 08:33, 16 March 2021 (UTC)
replies: text: , feel free to offer an alternative. -- DeFacto (talk). 08:39, 16 March 2021 (UTC)
replies: text: Frankly, I wanted to alter the existing picture: crop it, remove grass, maybe add a "blue tint" filter. Uchyot (talk) 12:19, 16 March 2021 (UTC)
replies: text: , you can upload a new image based on a current one - visit Commons to find out how. -- DeFacto (talk). 07:32, 17 March 2021 (UTC)
replies: text:  I think the image should not be cropped, because the context is needed to show the size of the block. The volume of it is the main point of the picture. A tonne equals this amount of concrete. Volker Siegel (talk) 20:07, 15 September 2021 (UTC)
thread_title:  Picture 

message: The term "relative mass" is used describing the mass of a container filled with water. The term usually is short for "relative atomic mass", which is unrelated to the context. The mass also does not seem to be specified relative to some other mass. I think the term "relative" should be removed from the sentence, but I might be missing something.
Full context: "An English tun (an old wine cask volume measurement equivalent to approximately 954 litres) of wine has a relative mass of approximately 954 kg if full of pure water, a little less for wine."
The sentence has other problems (the tun seems to have no mass), and does not add much, I'll remove it. Is there an actual meaning in the "relative"? Is it a reason to restore the sentence?
Volker Siegel (talk) 21:19, 15 September 2021 (UTC)
thread_title:  Relative Mass 

message: Well….. In my constant you should apply apply Aloe Vera and then take a nice cool bath. Try it for a week or so.. 43.250.241.216 (talk) 16:24, 28 April 2022 (UTC)
thread_title:  Things you should do to cure SunBurn 

message: Editors might like to join the discussion at Wikipedia talk:WikiProject Physics#Add ronna- and quetta- to units articles?. NebY (talk) 23:20, 18 November 2022 (UTC)
thread_title:  New prefixes