Even if that is true (and I don't believe it is true), we are promoting that SI be used by everyone, not just in scientific settings. The USA already predominately uses SI in science, but not very much in business and the every day lives of the general public. The general public uses the days, hours, and minutes as well as seconds. Thus if the general public is being encouraged to use SI seconds instead of conventional seconds, then we need to find a way to reconcile the SI seconds with the other time units the general public is using. Does anyone produce clocks or watches which only display time in seconds? All of the ones I've seen display no more than 60 seconds, then they use minutes, hours, and days for the longer time frames.
If 60 SI seconds already equal a conventional minute, then a conventional minute can already be thought of as part of the SI system, though not explictedly stated as such. If it is part of the SI system in anyway, then the SI system is inconsistant because the system is no longer using multiples of only 10, 100, 1000, etc. Further scientists are also using using minutes, hours, days, weeks, and months in their reports. For example many medical studies specify how long (in days, weeks, or months) the subjects paticipated in a particular experiment. How preceise are those medical/scientific findings if the time units being reported are not precise? Are the months being reported of 28 days, 29 days, 30 days, or 31 days? How many SI seconds are in each of the days. Likewise the NASA reports of launch, landing, and times of movement of their rockets, orbiters, landers, and Mars rovers are expresssed in not just SI seconds, but also minutes, hours, days (both earth days and Mars days), and weeks - even when all references to velocity, distance, mass, weight, and temperature in a in SI units in particular press releases. These examples shows that many scientists are using the same units as the general public (of minutes, hours, days), even if they are also using SI units for seconds, velocity, dosages of medication, etc. If hours are not considered a derived unit of the SI second and thus a part of SI, then why does the USMA and SI promote using kilometers/HOUR (km/hr) in place of miles/hour? If the hour is not considered a derived SI unit, then the USMA and SI should be promoting only saying kilometers/SECOND or meters/SECOND - instead of promoting use of the term kilometers/HOUR!!!! Why does the USMA tell people to use km/hr for road signs if the hours are not considered part of SI??? If hours are not a part of SI, then you are not following your own admonitions when you use the USMA server to promote use of the term km/hr. Hence the inconsistency of the time units being promoted by USMA and and many SI promoters, thus the need for decimal (aka "metric") time units! If the inconsistency or flaw of using hours does not exist in SI, then it exists in those who are promoting the use of the term kilometers/HOUR as a part of proper SI usage!!! Lets fix the SI system by using decimal time units, or at least insist on using m/s instead of km/hr!! Quoting Bill Hooper <[EMAIL PROTECTED]>: > [EMAIL PROTECTED] wrote: > > ... you seem to prefer to swallow up (or put up) with this clear flaw > > in the SI system > > Sorry, but days, hours and minutes are not part of SI and have never > been intended to be. They do not represent a flaw in SI. If anything, > they represent a flaw in the way we measure the time of day. The uses > to which scientific and technical time measurements (and units) are > used are so different from the ways in which time of day is used that > there does not seem to be any reason why the two need to be (or can be) > coordinated or reconciled. > > It's not a flaw in SI because it is not part of SI at all, and > therefore is not of much interest to proponents of SI (many of whom are > members of USMA and subscribers to this list). > > Regards, > Bill Hooper > Fernandina Beach, Florida, USA > > Gavin Young http://www.xprt.net/~hightech , http://www.renewableelectricity.com, http://www.electric-automobile.com
