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Re: [time-nuts] 15 ns vs. 15 nS

Jean-Louis Oneto

Tue, May 22, 2007 12:17 PM

At 04:05 AM 5/22/2007, Rob Kimberley wrote:

As Seconds are a fundamental unit of the SI system, shouldn't the "S" be
upper case?

Of seven SI 'base units' only two - K for thermodynamic temperature
and A for electrical current are capitalised. On the basis of your
suggestion we would need to campaign for a change in 5 units, not just
one.

John

Hi, the rule is that only unit names derived from people's name are capitalized, hence Volt, Hertz, Siemens, Kelvin, Ampere, Joule, Coulomb, Farad, Watt... The complete list can be found at: http://www.bipm.org/en/si/si_brochure/chapter2/2-2/table3.html (english version) Have a nice day, Jean-Louis Oneto OCA GEMINI - Avenue Copernic - 06130 Grasse - France ----- Original Message ----- From: "John Day" <johnday@wordsnimages.com> To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Sent: Tuesday, May 22, 2007 11:42 AM Subject: Re: [time-nuts] 15 ns vs. 15 nS > At 04:05 AM 5/22/2007, Rob Kimberley wrote: >>As Seconds are a fundamental unit of the SI system, shouldn't the "S" be >>upper case? > > Of seven SI 'base units' only two - K for thermodynamic temperature > and A for electrical current are capitalised. On the basis of your > suggestion we would need to campaign for a change in 5 units, not just > one. > > John >

James Maynard

Tue, May 22, 2007 3:49 PM

Jean-Louis Oneto wrote:

Actually, the rule is slightly different. To quote the English version
of the BIPM's SI brochure, section 5.2, "SI unit symbols" :

In general, unit symbols are written in lower case, but if the name of
the unit is derived from the proper name of a person, the first letter
of thesymbol is a capital. Whenthe name of a unit is spelled out, it is
always in lower case, except when the name is the first word of a
sentence or is the name "degree Celsius".

Ou, en français:

En général les symboles des unités sont ecrits en minuscules, mais, si
le nom de l'unité dérive d'un nom propre, la première lettre du symbole
est majuscule. Le nom de l'unitè proprement dit commence toujours par
une minuscule, sauf s'il agit du premier mot d'un phrase our du nom
«degré Celsius».

Jean-Louis Oneto wrote: > Hi, > the rule is that only unit names derived from people's name are capitalized, > hence Volt, Hertz, Siemens, Kelvin, Ampere, Joule, Coulomb, Farad, Watt... > The complete list can be found at: > http://www.bipm.org/en/si/si_brochure/chapter2/2-2/table3.html (english > version) > Have a nice day, > Jean-Louis Oneto > OCA GEMINI - Avenue Copernic - 06130 Grasse - France > Actually, the rule is slightly different. To quote the English version of the BIPM's SI brochure, section 5.2, "SI unit symbols" : In general, unit symbols are written in lower case, but if the name of the unit is derived from the proper name of a person, the first letter of thesymbol is a capital. Whenthe name of a unit is spelled out, it is always in lower case, except when the name is the first word of a sentence or is the name "degree Celsius". Ou, en français: En général les symboles des unités sont ecrits en minuscules, mais, si le nom de l'unité dérive d'un nom propre, la première lettre du symbole est majuscule. Le nom de l'unitè proprement dit commence toujours par une minuscule, sauf s'il agit du premier mot d'un phrase our du nom «degré Celsius».