Martin Bonner wrote:
Paul Giaccone Sent:
Martin Bonner wrote:
Paul Giaccone Sent:
Centi-, deci-, deca- and hecto- are not officially part of SI nomenclature.
That's not what the Bureau Internatoinal des Poids et Mesures (http://www.bipm.org/en/si/si_brochure/chapter3/prefixes.html) says.
Interesting... I stand corrected. But are they in official scientific use?
Does the second officially take any prefix? Can you talk about a "megasecond",
Yes. (Although it is EXTREMELY unusual).
Quoting your source back at you, Martin... according to the section at the bottom of the page, you can't officially say "megasecond".
Paul
Are you refering to the text: "Prefix names and symbols are [...] never used with the units of time: minute, min; hour, h; day, d."
I read that section as saying you can't use mega with minute, hour, and day. So megasecond is OK, but kilohour is not. (If you read it as applying to ALL units of time, it means you can't use millisecond either - which would be silly!)
Yes, that's quite true. But I think you can also interpret it as meaning (even if it does not actually say this explicitly) that SI prefixes are not used with multiples of a second ("megasecond", etc), (but are OK with submultiples, like you say) and that "minute", etc, should be used instead. Paul