Re: SI prefixes with "accepted" units, others

Thanks Paul. You're right about "ha". That probably shouldn't take a
prefix. The list gets shorter and shorter...

    Neil


On Tue, Nov 12, 2024 at 12:22 PM Paul Libbrecht <paul@hoplahup.net> wrote:

> Hello Neil,
>
> On 12 Nov 2024, at 21:06, Neil Soiffer wrote:
>
> My conclusion is that only au, ha, l, t, Da, and eV accept SI prefixes in
> practice. I'm definitely open to revising that if someone can show that is
> not true (of course, people with do all sorts of "wrong" things, but if
> enough people do that, then it is acceptable...).
>
> I am surprised ha would carry SI prefixes since ha is “hundred ares” (an
> “are” is the surface of 10x10). Just as 1 hectolitre is 100 litres.
>
> FYI: I hadn't realized this, but "neper" comes from "the neperian (or
> natural) logarithm". The bel (named after Alexander Graham Bell) is log_10.
> All typically reference some quantity (e.g., 3dbW) because they are just
> ratios.
>
> Erm… you mean. “All do not reference some quantity since they are just
> ratios” (Just as an angle)? Right? (Or maybe you mean that the unit is
> implicit?)
>
> Paul
>