Jim wrote "SI community (CGPM, CIPM, BIPM, etc.) did not favor this practice at all, with a few exceptions". The practice of using non-SI with SI unit.
Hour is a non-SI unit, but km/h, kilowatt-hour are used worldwide. In the same way, if someone writes km/day or kilowatt-day, will anyone jump on them. Meter is based on the distance from the pole to the equator, so why not time be based on our planets rotation. Just an argument. FYI: Internally the computers store the date in a 'single number' which is '# of days' from a particular base year and the time as a decimal part of the day. For ex :- The date 2002-03-05 and time 13:35:00 will be stored as 37320.57. This way the computers work faster in calculations. Madan --- "James R. Frysinger" <[EMAIL PROTECTED]> wrote: > Date: Tue, 05 Mar 2002 10:53:34 -0500 > From: "James R. Frysinger" <[EMAIL PROTECTED]> > Organization: Metric Methods > To: "U.S. Metric Association" <[EMAIL PROTECTED]> > CC: "U.S. Metric Association" <[EMAIL PROTECTED]> > Subject: [USMA:18545] Re: Fwd: "How many miles..." > thread > Reply-to: [EMAIL PROTECTED] > > M R wrote: > > > > Jim Frysinger wrote > > "With those seven base units and their derived > units > > you can measure just about everything but true > love." > > The unit of love is $/? (euro). The more you > spend, > > the more you love - just kidding. > > > > If 'day' is a SI unit, then its fantastic as we > can > > use deciday, centiday, milliday, etc. MS-Office > Excel > > and Star-Office Calc gives function to measure > decimal > > day. > > > > Am I right. > > Madan, you're a cynic! (grin) > > As for prefixing "day", I asked our national > representative on the CCU > about something similar some time ago. Though there > is nothing explicit > about prefixing the "non-SI units authorized for use > with the SI", he > said that the SI community (CGPM, CIPM, BIPM, etc.) > did not favor this > practice at all, with a few exceptions. Liter, tonne > (metric ton), > neper, and bel are often prefixed but not the time > or angle units. The > second, a base unit, is often prefixed, of course. > > I have adopted the practice in my labs of > periodically reminding > students on the time remaining, in order to help > them budget their time > and to keep from getting bogged down. When I used to > announce the time > remaining in hours and minutes, I was "not heard". > Then I started > announcing the number of kiloseconds remaining; all > talking in the lab > ceases immediately and everyone looks at the clock. > Mission > accomplished! Also, it usually leaves a grin on the > students' faces. > > Jim > __________________________________________________ Do You Yahoo!? Try FREE Yahoo! Mail - the world's greatest free email! http://mail.yahoo.com/
