Half a croissant, on a plate, with a sign in front of it saying '50c'
h a l f b a k e r y

idea: add, search, annotate, link, view, overview, recent, by name, random

meta: news, help, about, links, report a problem

account: browse anonymously, or get an account and write.




Universal unit of velocity
  (+3, -10)(+3, -10)
(+3, -10)
  [vote for,

The "standard" units of velocity (miles per hour and kilometers per hour) have at least two significant disadvantages: They are tied to arbitrary, artificial measures of distance and time, and because they are based on either the Metric or English distance systems, there is often needless confusion when speeds are discussed in international forums.

Better (more universal) velocity units are based on independently measurable physical or terrestrial properties, such as the speed of sound at the Earth's equator at sea level (the "Mach").

Unfortunately, one Mach is over 700 miles per hour, which makes it just about right for discussing airplanes and bullets but rather unwieldy for communicating automobile speed limits or the how fast the wind is blowing. 1/1000th of a Mach, however, is in a very convenient range for use in everyday life, being a little faster than one km/hr but a little slower than one mi/hr.

I propose that miles per hour and kilometers per hour be abandoned in favor of milliMachs.

mab, Aug 10 1999

My Atom and his Package http://www.atomandh...com/mp3s/metric.mp3
Song my Atom and His package. Not about Millimachs, but relevant to the debate over there -> in the sidebar. [johan, Aug 10 1999, last modified Oct 04 2004]

Notes on measures http://www.ex.ac.uk.../dictunit/notes.htm
Includes definitions of yard, metre, etc. [pottedstu, Aug 10 1999, last modified Oct 04 2004]

Metric system in the US http://www.unc.edu/...units/usmetric.html
OT, but a good discussion of the history of the Metric system in the US [toiyabe, Oct 04 2004]


       There are two problems with using the speed of sound as a unit for velocity. The first is that it's really variable (with pressure, temperature, even humidity); the second is that it's terribly geocentric. High-energy physicists already have a system of "natural units" which avoids this: measure everything as a fraction of the speed of light, c = 299792458 meters/second. Perhaps we want to use micro-cs for terrestrial purposes?
cosma, Dec 03 1999

       The meter is the length of the path travelled by light in vacuum during a time interval of 1/299,792,458 of a second. It's already tied to nature. But the MilliMach sounds cooler.
bretp, Dec 14 1999

       From furlongs/fortnight to parsecs/picosecond--all mensuration is futile!
jimfl, Jan 06 2000

       "Hogshead or Half a Butt". Gotta love the English System.
dean, Jan 07 2000

       The freeway speed limit in California is 65mph - this could be easily changed to 100nc (nano-c) - about 67mph
hippo, Mar 30 2000

       Measurement systems based on c as measured via meters, seconds, or other geocentric/cultural units would work fine, but are too much work to reconstruct (in the absence of, say, the earth as a frame of reference) to be thought of as *truly* elegant. "The distance traveled by light in a vacuum in 1/299,792,458 of a second"? Please. The real challenge is to use whole-number multiples of things that could be explained without reference to other systems of measurement. An atom of hydrogen is an atom of hydrogen, and does not vary (it seems) with pressure, temperature, or velocity; what can we construct using whole (I suggest powers of 2, since base 10 is likewise phalangocentric) multiples of hydrogen atoms? Define a measure of distance, with which to select a whole-number wavelength of light to use as the standard for time. (ref. Feynman's lecture in which he tries to explain to an alien which way is *left* for more fun in creating absolute references)
jplummer, Mar 31 2000, last modified Apr 04 2000

       Despite my previous annotation to this halfbakeme (?) I'm now leaning away from the idea of having units of length, speed, etc. based on very big things (like c) or very small things (like Plank constants). I believe that people relate to units best when they're based on something which has real meaning in everyday life - e.g. a foot (the length of someone's foot), rather than a metre (some fraction of the distance between the equator and the north pole, or some number of wavelengths of a certain colour of light). Of course the problem with most everyday measurements is that they're not universal - not everyone's feet are the same length - and many other things you choose like say, paper sizes (A4, Letter, etc.) are not the same worldwide. So my solution is to choose things which are at least commonly understood, (and which can then be accurately redefined in terms of the number of wavelengths of a certain colour of light, or whatever). Here we go then - my commonly understood unit of length: The length of a Bic biro (ballpoint for US viewers) - and my commonly understood unit of time: The length of a (U.S) phone ring.
hippo, Apr 04 2000

       I think that's the biggest reason that Americans are resisting the Metric system. The units may be more 'convienent' but they don't MEAN anything. Most people can make a quick guess at a 'foot', but '33 centimeters' can't be visualized easily.
StarChaser, Apr 06 2000

       i was always fond of the original definition fo the yar: the distance from the tip of the king's nose to the tip of his middle finger when held out at arm's length.
urbanmatador, Apr 07 2000

       get the US finally get some sense and switch to metric FIRST, then we can discuss a more rigorous standard. People here just don't understand - metric system metric system metric system! have some standards, people!
jearbear, Apr 07 2000

       We have standards. Not OUR fault if you want to use some goofy decimal system that doesn't make any sense. When was the last time anyone used a decimeter?
StarChaser, Apr 08 2000

       How about, for a basic unit of time, the nanocentury (pi seconds, to within 0.5%)
supercat, Jan 09 2001

       Ahem, supercat. That one's mine, as you will find if you look up nano- in the hackers' dictionary.
td, Jan 09 2001

       Indeed so. I did not mean to imply that it was of my own devising (the "fortune cookie file" entry I had credits it to "Tom Duff", which appears to be you!)   

       How, if I may ask, did you come up with that observation?
supercat, Jan 09 2001

       Here are the new official units:   

       length: the inch mass: the pound volume: the pint time: the hour   

       But put it all in base 12. Why use these measures? Because they developed more or less naturally. They are tried and true.
Vance, Jan 29 2001

       Supercat: As with many old stories, this one is way longer and more boring than it should be.   


       A bunch of engineers, formerly from Ampex, but at Lucasfilm when I first knew them in 1981, had pointed out that 3 sec., which they referred to as a nanocentury, was about the limit of human patience in many user-interface situations. My only part in the enterprise was to point out that a nanocentury was near enough to pi seconds to make it a good rule of thumb for converting years to seconds and to cast the aphorism in its final form (and to retail it to John Bentley, who popularized it in his Programming Pearls column and books.) The Ampex guys included Tom Porter, Adam Levinthal and Rodney Stock. I remain unsure as to who is responsible for what parts of this.
td, Feb 06 2001

       vance - "the pint time: the hour" The pint time : the Happy Hour
galactus, Feb 06 2001

       jordaan: Swatch created something like that. They call it beat time. Each day has 1000 "beats", beat 0 being midnight in winter in Biel, Switzerlad.   

       No time zones or anything...   

       Now, I'm all for the metric system (I actually had trouble with the english units when I lived in the US.), and a decimal time system is great... but you have a problem when no one else uses it. If you have to do a conversion every time you talk about the time, then you have a problem... it's bad enough having to do it with people on the Internet, but imagine trying to do it every time you want to catch the bus, or whatever.   

       Let's get the US and Liberia to use the metric system... They're the only non-metric holdouts left. Once that's over and done with, we can start breaking ground elsewhere.
C-Bud, Feb 09 2001

       Apparently the British yard is defined in terms of the metre. The Weights and Measures Act of 1963 decreed that "the yard shall be 0.9144 metre exactly". Yay metric! (link)
pottedstu, Oct 11 2001

       The reason why they call it the Imperial system is because it's a royal pain to use.
Amishman35, Dec 02 2003

       BTW, has everyone here tried typing "speed of light in furlongs per fortnight" in Google?
supercat, Dec 02 2003

       The US does NOT use the Imperial system. It uses the US Customary system. Big differences are the gallon (1 US gallon = 0.83267 Imperial gallons) and other volumetric units.
toiyabe, Dec 02 2003

       Metric Time:   

       vebaday = .000 01 day = .014 standard minutes = .84 standard seconds milliday = .001 day = 1.44 standard minutes centaday = .01 day = 14.4 standard minutes deciday = .1 day = 2.4 standard hours day = day Decaday = 10 day Hectaday = 100 day = 1.33 standard months (standard) Kiloday = 1 000 day = 2.74 standard year   

       The standard work week would be a Decaday. You'd work First, Second, Third, then have Fourth off. Then you'd   

       work Fifth, Sixth, Seventh, Eighth, and have Ninth and Tenth off. This would result in you working 70% of the   

       week. In the standard system, you work 71% of the week.   

       There would be no months, dates would be the year and the day of the year. So today would be 0059-336 59 years   

       since the first atomic weapon was detonated, then the 336th day of that year.   

       Note: veba is a prefix that I made up for .000 01. If anyone knows a real prefix, let me know.
GenYus, Dec 02 2003


back: main index

business  computer  culture  fashion  food  halfbakery  home  other  product  public  science  sport  vehicle