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Uncle Sam's Funhouse 133

Posted by michael
from the peewee-is-not-invited dept.
carlie writes: "Ever wonder who's taking care of the 'National Kilogram'? Have a 40 foot structure you need tested to 12 million pounds of pressure? How about a 6 foot aluminum sphere with microwave plasma lamps called the 'Black Ball of Sunlight' to check that new polymer for photodegradation? The online version of the Washington Post has an article about the National Institute of Standards and Technology in Gaithersburg, where all this and more occur daily."
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Uncle Sam's Funhouse

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  • Still rely on the French to define your unit of mass, eh? (Rusting, other chemical readtions with the block. Bye bye perfect reference!) And the meter being the distance from the North pole to the equator thru Paris divided into 10,000,000 parts? Yah, that's real accurate (/me kicks some dirt, or it rains. Oops, time to remeasure). And what have you got to define the second? 1/86400 of a solar day? A sideral day? The earth is slowing down and accelerates when nearer to the sun, peturbations from all the shit in the sol system. And that gravity thing that even affects cesium oscillations of cesium atoms. Great accuracy there.)

    Despite the rhetoric, the metric system is totally arbitrary. No mystical perfect basis to it. Water is just another liquid. (And your kg mass isn't even that. It's a PtIr alloy). As made up as the English system of units.

    Or sure, you will now claim that the meter is defined by x wavelengths of y angstrom emmissions of excited Kr atoms and no doubt state with pride how the second is defined by n oscillations of cesium atoms. All hail metric. And well, The kg is still a slab of metal in Paris, though (/you sweeping facts under carpet). And Kr emmissions and Cesium oscillations will vary from sea level to the top of Everest of even a foot (or 30.48cm higher toy meter freaks? Or is it metre freaks?)) And that for this reason metric is superrior to English units?

    Well, the *same technology* already defines the foot, second and slug. No better. No worse. Metric could've been built on English units and used kilofeet, millislugs, etc. (base 10 works in any system right? And need not be privy to metric?) and remained backwards compatible, but nooooooo. Snooty Frogs had to be different and l33t and reinvent the wheel.

    The metric system is an evil plot to make us strip bolts, wrongfully crash probes into Mars, and use numbers that don't divide evenly by anything other than 2 and 5. A mile may be 5280 feet but that quantity divides EVENLY by 1, 2, 3, 4, 5, 6, 8, 10, 11, 12, 15, 16, 20, 22, 24, 30, 32, 33, 40, 44, 48, 55, 60, 66, 80, 88, 96, 110, 120, 132, 160, 165, 176, 220, 240, 264, 330, 352, 440, 480, 528, 660, 880, 1056, 1320, 1760, 2640, 5280. A km is 1000m and divides evenly by 1, 2, 4, 5, 8, 10, 20, 25, 40, 50, 100, 125, 200, 250, 500, 1000. Making messy decimals more likely. And non terminating decimals when dividing by I guess bizarre everyday numbers like 3. Geez.

    BTW, why is the base unit of mass in metric the KILOgram, shouldn't it be the gram? And why do people state "weight" or "thrust" in kilograms? Why not Newtons? Why do tires not list inflation ratings in Pascals? Why do we still ask for a "pint of ale" in the UK? If you wanted a universal constant for temperature, why did Centigrade scale not at least use absolute zero as one anchor point? And if base 10 is so l33t, where is metric time? Base 60? Why stick with millenia old numbering from Babylonian times yet praise base 10 everywhere else.

    Sure English units are fucked. At least we admit it. But it learns just as easy as anything else. It evenly divides better by everyday numbers. Why to the metric heads think their shit don't stink and that metric is from the hand of God? It's as fucked as any other measuring system. More so because it's proponents won't admit it's just as arbitrary.

  • Americans are such idiots.

    Non-Americans are such idiots.

    I love when two minds of equal mental ability collide in fantastic debate! The stunning amount of facts supplied by both side to back up their arguments. The equal dismantling of the other side's arguments. Yes. This is one for the textbooks. The immobile object (USA) and the irrestible force (the metric system).

  • weight: the kilogram is no longer defined in terms of water. Sorry, I can't quote the current definition, but it's something more basic. People state weights in kilograms because people are ignorant. People state masses in pounds for the same reason. distance: sorry, the definition in terms of the wavelength of radiation produced in a certain process is no longer used. The meter is now defined as the distance light travels in 1/299792458 seconds exactly. temperature: the official SI temperature scale is the Kelvin scale, in which 0K is absolute zero. numerical base: sorry, I can't give any argument that would lead to preferring one base over another. We use babylonian time measures because they are convenient in everyday life. We use units of days, months, and years (in science)because they are very important cycles in biology and astronomy. However, for physical science, only the second is used. It would be nice if people who posted knew a little more about what they were talking about.
  • by Anonymous Coward
    I've been using NIST for setting the time on my home PC. All you have to do is telnet on port 13 (daytime) to the NIST time server and it will respond with the date and time in the header. Parse the header for the correct time, add/subtract your timezone offset and set your PC time.

  • by Anonymous Coward on Wednesday April 04, 2001 @09:14PM (#314003)
    "The metric system is the tool of the Devil! My car gets 40 rods to the hogshead and that's the way I likes it!" - Abe Simpson
  • Well I know of 1 place that they messure lenght in Smoots. At some point an MIT Frosh got a bit drunk and his frat brothers decided to help him with a homework assignment to messure something with a non standard unit. They used him to messure the mass ave bridge. (AKA The Smoot Bridge) if you dirve across it you can still see the smoot marks. But I'm not sure what they standard lenght of a "Smoot" is.

  • You're a Jew. Your views are invalid and even dangerous. Please refrain from posting to Slashdot.

    And you are a little shit who does not even have enough courage of your beliefs to sign your name.

    Next time you want to insult me sign your name.

    So many Hamens only one Purim.
  • That would be fine if Microsoft published the standards so that others could use them.

  • I always thought the NSA handled this... or at least they would have the most input into any of the things related to security....
    enhance digital information security by publishing an advanced encryption standard and guidance for federal agencies on its use;
    [snip]

    The NSA is not terribly well know for sharing secrets, especially encryption secrets. We need an openly developed and studied encryption system. The advanced encryption standard discussed above is the Advanced Encryption Standard, which NIST chose last October [slashdot.org]. The AES will be a boon for government and private industry, giving the world a trustworthy, peer-reviewed encryption system that everyone can agree on. Government needs an encryption system and wants the best one possible. The American people deserve to know what system our government is using so that we can check it's quality ourselves. Someone needed to make this decision, and it was NIST's job. I'm quite happy with their effort. The world's top cryptographer all agreed that Rijndael (AES) is something they would be comfortable.

  • Actually, people generally measure their heights in centimeters.. I'm 169cm, your wife is 146cm, you are 167cm..

  • Is it strange that EVERYTHING at the N-I-Standards-T is decidedly UNSTANDARD?

  • Soon they would be irrelevant: In 1866 Congress declared the metric system to be the basis of measurement in the United States. You read that right. Even
    though most Americans still aren't entirely clear how long a centimeter is, for more than a century the metric system has been the foundation on which
    American measures were defined. In 1893 the U.S. pound was officially described as 0.4535924277 kilogram, and the yard, 3600/3937 meter.


    Given the problem with NASA and that we are truly going into a century of science. The USA needs to move to the metric system. It may take 25 years but it worth it. The US need to stop thinking they live in a bubble.
  • NIST has a *MINISCULE* budget compared to that asinine black hole of a military system you guys keep pouring most of your money into.


    --
  • OOoohhh!! I like that!

    Let's get Peter Molyneaux in to hack the Slashdot code a little -- I want a Black & White interface for Slashdot, so that I can pick, oh, say, Katz as my animal alter-ego. Whenever he posts a new article, I'll get to bitchslap him 'til he cries!

    Of course, there'll have to be some sort of physical interface down at Slashdot HQ, so that the graphic interface can be translated to actual abuse...

    --
  • So does Japan, for that matter.

    Go you big red fire engine!
  • by peter303 (12292) on Thursday April 05, 2001 @06:49AM (#314014)
    It was originally defined as the weight of volume of water the size of a fractional circumference of the earth at a particular temperature. Being difficult to reproduce, this was switched to a reference physical object of this weight.

    The annual standards issue of Physics Today (March 2001, p32) suggest making mass a "derived unit". These would come from two fundamental equations of physics- E = mc2 and E = hv giving m = hv'/c2.

    C is the speed of light

    v' is a vibration rate defined as some highly stable atomic vibration known to 18 decimal places such as in an atomic clock. The prime refers to a frequency chosen to be exactly a kilogram.

    h is Planck's quantum of action, measured independently in other experiments.

  • by Lumpish Scholar (17107) on Thursday April 05, 2001 @02:51AM (#314015) Homepage Journal
    NIST (formerly the National Bureau of Stanards) is also the home of Expect [nist.gov], a Tcl-based tool for automating all sorts of stuff. It was designed as a system administration tool, but has become incredibly popular for test automation.

    Expect is not GPL'ed; by law, it's public domain.
  • by augustz (18082)
    Yes, NIST was involved in a new encryption standard, and contrary to what you seem to be implying that was a good thing. Crypto standards sponsored by inteligence agencies seem to have a tendency to turn out to be not as secure as they should have been, strange until you realize that these very same agencies need to break the encryption as part of their job.

    Some folks realize that there is a value to using encyption other than to hide ones world domination plots. Thanks to the NIST, we've now got a PATENT FREE, openly developed set of technology, which has been really worked over in the best sense by a lot of smart people.

    I'd willing pay the millions to keep some of the science being done patent free, especially science that will become a standard.

    The alternative is the verisigns and network solutions of the world. The cost may be harder to pinpoint but it is real. So rock on with at least this bit of "pork barrel" spending.

  • Would the sphere be abel to cook anything like a Thanks Giving turkey?

    I don't know, but it would give you one hell of a tan.

  • haven't you ever been hit in the eye by flying ketchup?
  • If your press is less than 40 feet tall, our press will actually crunch yours. Of course, in the process whatever is within your press will really get crushed...

    Many years ago the instrumentation company MTS [mts.com] provided a device to test to destruction a mine jack. Yes, they built a machine to crush a machine which was designed to hold up the rock roof of a mine and measure the entire process. I wonder if that is this device.

  • by macsforever2001 (32278) on Thursday April 05, 2001 @04:42AM (#314020) Homepage

    In fact I recall I think it was 20/20 or 60 minutes which had an article where researchers were being paid high salaries to test the flow of ketchup (catsup/ketsup) and if it was thick enough for the American market.

    What is it with luddites on Slashdot? NIST [nist.gov] is a vitally important hi-tech facility that does far more than simply measure the viscosity of ketchup. I live 5 minutes away from it and have been there many times and I never knew this. Taking one *minor* area of research and blanketly saying they aren't necesary is a disservice to NIST and the country (USA). BTW the reason I *don't* work there now is because I can make more money in the private sector. My dad worked at NIST (not on this alleged ketchup project) and I have surpassed his salary.

    Surely someone can regulate what constitutes a neccessity, but why not branch some of these things to academia, where things are always revolutionary changing constantly to keep up to date, as opposed to following standards set eons ago.

    You don't understand what they mean by standards. They can very accurately measure flow rates (like at your gas pump), weights (for commerce), lengths (for better manufacturing), etc. They aren't about establishing standards (though they do sometimes) so much as QA of current standards like the meter, the US pound, etc.

    Government can cut budgets by passing some of these tasks to colleges, then pay the universities to keep track of this at the fraction of a cost, keep students excited about helping government, and saving us all some money.

    Um how? You mean by giving them more money? The government already gives state Universities money. What proof do you have that a bunch of students often more concerned about getting drunk can do what phDs at NIST do better and for less money? They serve different purposes and handle things that University research can't do.

    NIST is one of the reasons that America is at the leading edge of technology. NIST and research labs like it employ *many* phDs from all over the world. Believe me, there are far more intelligent people at NIST than any of the Fortune 500 companies I've worked for. If we cut funding to NIST then many people will not have a reason to get a phD because there will be no jobs for them (outside of Universities). Guess what? Many smart people will leave the country and go to other places with hi-tech research and we will become an insigificant country.

    Here is a *small* list of the many important things that NIST does:

    Just because you don't know or understand what they do doesn't mean it isn't important.
  • In 1791 the FAS decided to define the meter as 10^-6 of a quadrant of a meridian (i.e. one millionth of the distance from the equator to the north pole), as we all learned in high school.

    It's a peculiarly awkward definition, because it really can't be measured in the laboratory. In fact, it fixes the meter to a kind of simple sounding theoretical shape that doesn't correspond to physical reality without all kinds of unsimple geometrical qualifications. The Earth is somewhat pear shaped, not spherical, and local topography means that the arc that defines the meter is usually well underground. It's a tremendous surveying task to determine the length intended.

    So, why did they choose to fix the meter at the length they did?

    Well, it turns out that the length they had in mind was the length of a pendulum having a half period of one second. A reasonable facsimile of a standard could be fabricated by any compenetent clockmaker, who could be found in any technologically advanced country due to the importance of chronometers for navigation. The accuracy of such a standard could be checked by ensuring the pendulum swung back and forth 43200 times between noon and noon the next day.

    The problem is that there were slight gravitational anamolies from place to place on the Earth. To really fix the length of the meter, they would have to fix it as the length of such a pendulum at a specific spot on the Earth -- most likely Paris. This was obviously a matter of political prestige, so they chose a definition which was more diplomatic, but harder to measure. In fact, in practice they ended up going by a physical artifact -- a bar of platinum iridium alloy stored in Paris.

    Which was a good thing because they got the surveying wrong. Measuring by the practical standard they produced, one millionth of a quarter of the meridian passing through Paris was 1.0002 meters: remarkably good for surveying, remarkably bad for standards setting.

    Much later, this was physical standard was replaced by a definition based on the wavelength of radiation from an isotope of Krypton. This lab friendly definition was later replaced by a definition of the meter based on the speed of light. It is the distance travelled by light in a vacuum in a defined faction of a second.

    Which means once again, the meter is linked to the second.

  • There is an ongoing dispute between male and female researchers at the NIST over the exact size of six inches.
  • The US is switching over to metric time some day, mark my words. Remember this moment, people: 80 past 16 on the 35th of March.

  • Slashdotters will be interested to know someting that wasn't mentioned in the article: NIST is a hotbed of Beowulf cluster activity. Dr. Mark Edwards, who is working on Bose-Einstein condensates while on leave from my universisity, has built a multi-layered cluster of over 100 nodes using 266 MHz PII machines acquired from the Bureau of the Census. With encouragement and seed money from Edwards (or more precisely, from the National Science Foundation), a group of undergraduates at Georgia Southern University has built a 16-node cluster out of junk P-Ones, and is planning another one. (I know about this because I am one of the project's faculty advisors.) The success of the cluster has attracted enough attention from the university administration that Linux is being seriously taken into account here for the first time.

    It's remarkable that this sort of heavy-duty research effort is being carried out by undergraduates -- this is what Linux and other free software make possible. The tools are there if you have the ambition. Have a look at our Georgia Southern Beowulf Cluster [141.165.40.55] website.

    Dr. Davis Robinson
    Associate Professor
    Dept. of Literature and Philosophy

  • Sorry, i meant that England is the only EUROPEAN contry with left-side traffic

    Ireland too.

    -Bruce
  • Most importantly is India which makes up about half of the world's left-hand drivers.

    Of course left and right would be about tied if not for China.

    But if you want to see something really crazy, go to Burma where they drive on the right, but their steering wheels are also on the right (cars are imported from Thailand and Japan.) The drivers can't see around the car in front of them when they want to pass, so they just start honking and slowly moving into potentially oncoming traffic. And drivers coming the other direction also always honk whenever they pass a car going the other direction. Exciting stuff!

    -Bruce
  • by superid (46543) on Wednesday April 04, 2001 @08:45PM (#314027) Homepage
    Two examples that make your case. 1) Internet RFCs, keeping (network) commerce and business flowing. The RFCs will undoubtedly go down as one of the most successful collections of standards ever (IMHO of course). Now take ANSI SQL. Implemented haphazardly by various independent self serving organizations. ANSI SQL does not drive interoperability between platforms except at the simplest level.

    SuperID
    Free Database Hosting [freesql.org]
  • That car gets REALLY bad gas mileage.

    Dunno 'bout anyone else, but my car gets AT LEAST 500,000 rods/hogshead.

  • Beware of Microsoft's attempts to infiltrate the US electrical power market!

    Microsoft announces new electricity protocol [segfault.org]

  • The easiest way for America to change over is to change what is taught in schools first, then start placing both types of units on consumer products. When that generation has grown up, there will be no need for the old units and they can be dropped.

    That ws the theory when I was in elementary school (1976-1981). We were only taught the metric system. To this day I still get confused by quarts, gallons, pints, and cups.

    But the only area where metric has really caught on are liter bottles of water and some liquors, in grams of drugs (legal and illegal), and in measuring the diameter of bullets.

    Tom Swiss | the infamous tms | http://www.infamous.net/

  • Only at around 4 degrees C. All bets are off for different temperatures, and it has to be 100% pure. If you have to be that precise, I don't see the point in linking them.

    You don't see the point ? I see it : if I have to carry around 5 bottles of 1 liter of milk, I can say I have to carry around 5 kg with an excellent precision (less than 1% error, if you don't count the bottle packaging). Don't need complicated computing to go from here to there : just need to change the unit. Nothing else can be easier.

    Multiples of 10 are fine if you only want to deal with decimals. But how do you write out a third of a kilometer?

    1/3 kg if you need precision, or 1.33.. (depending on the required precision). I thought fractions were part of the math teaching in school in US...

    Then you are trying to force the universe into your base 10 system, instead of adjusting your system to the universe.

    And how are the English units more adjusted to the universe ? Are you counting in base Pi or something along that line ? You are just using a bunch of various centuries old units that don't fit together. They are fine all by themselves but as soon as you need to convert, it's a mess, because no one took care of making them relevent to each other.

    By that argument, then, we should use a system that is based on SEAwater, not pure water. And what's the freezing point of seawater? 0 degrees Farenheit.

    Again you are wrong. The water from the Dead sea doesn't freeze at 0 degree fahrenheit. There's not one sea water but different sea water with various degree of salinity and other components (including microscopie algae). Basic a unit on this soup is stupid. On the other hand there's only one kind of pure water.

    The easiest way to get 100% pure water is to make it from pure hydrogen and oxygen. And if you already have the hydrogen handy

    So ?

    And, on the other hand, while not all that abundant on Earth, hydrogen is hands-down the most common substance in the universe. So shouldn't we be using it by your own arguments?

    No - unless you leave on a hydrogen cloud somewhere in the galaxy. Humans will (for a long time) still leave in oxygen and water based environement. Basing their liquid units on water makes sense.

    ...filtration device set up to get perfectly pure water. At least Farenheit lets you go down to the beach to get your water.

    ...and again get incorrect results, as there's not one kind of sea water.

    So 32.2 is an inherently more difficult number to learn than 9.86? 14.7 is more difficult than 101325? 93 million harder than 149 million? 2.997 E 8 is worse than 9.835 E 8? 491.67 makes less sense than 273.15?

    That's not the point. The point is that all distance/mass metric units convert between each other flawlessly with only the move of a comma. English units require a multiplication/division by a constant for EVERY unit change. So you need to learn all those constants.

    By using measurement systems that include more primes as divisors (even if it's just the addition of 3), you're giving yourself more room to manuever in which to state a measurement with precision instead of an approximate decimal

    If you want precision use fractions. Nothing can replace them, not even your old English units. If you can leave with a degree of error, then use a base 10 : it's very easy to learn and use (just a comma to move). Why would you bother with a bunch of incompatible units that needs odd constant to switch from one to the other ? just because some of them are divided by 3 ? Following you logic, we should all count in base 84 because it's a multiple of 1,2,3,4,6 and 7 ? That's silly. Besides, even with your English units you still count in base 10 anyway, so you could as well use units that are 10 multiplies of other units.

    Knowing that the meter was originally based on the circumference of the Earth as measured along the line of longitude through Paris, France does almost nothing for me.

    That's the only point I'll concede you. But I don't think it's a high price to pay if that means you can just convert units without a calculator.
  • by Betcour (50623) on Wednesday April 04, 2001 @11:10PM (#314032)
    Metric could've been built on English units and used kilofeet, millislugs, etc.

    Buzzzz. Wrong. Thanks for playing !

    The metric system is linked : a liter of pure water weights exactly 1 kilogram... woud you care to remind us of how many ounces weight a gallon of water exactly ?

    A mile may be 5280 feet but that quantity divides EVENLY... A km is 1000m and divides evenly

    Yep, but I'd rather use units that have less multiples but have 100 as one of them that a unit that have more multiples but only ones like "176 or 165" like your miles. How often do you count in base 176 exactly ?

    Water is just another liquid.

    No - it's the raw liquid most commonly available on earth, and almost the only one. Liquid hydrogen or nitrogen is not easy to find, neither is raw mercury. Only a fucked up mind would base it's unit system on another liquid than water. Or someone who lives on Jupiter (hint : you don't).

    If you wanted a universal constant for temperature, why did Centigrade scale not at least use absolute zero as one anchor point?

    There's some sense to this but :
    - absolute 0 temp has only been known quite recently, and by the time it was found temp. units were firmly established worlwide. There was not time to wait for the (possible) discovery of absolute 0
    - centigrades are based on freezing and boiling point of pure water at sea level. That's a unit fairly easy to understand for anyone on earth, as long as you know how to make a fire and have an idea of what ice looks like.

    Sure English units are fucked. At least we admit it. But it learns just as easy as anything else.

    No it doesn't. Really.

    It evenly divides better by everyday numbers.

    If you consider (I quote you) 33, 40, 44, 48, 55, 60, 66, 80, 88, 96, 110, 120, 132, 160, 165, 176, 220, 240, 264, 330, 352, 440, 480, 528, 660, 880, 1056, 1320, 1760, 2640, 5280 as everyday numbers, then maybe. But my everyday number is 10. Mastering multiplication/division by 10 is all you need to manipulate ALL metric units. You can use your fingers for all of them. Can't be easier than that.
  • indeed.. it should have been (+1, insightful) rather than informative.

    //rdj
  • NIST discovered the 5th state of matter!!! [nist.gov] NIST scientists receieved a nobel for this discovery a few years ago!!
    NIST runs MEP [nist.gov], one of the few government programs that generates a profit while aiding small business development in america.
    NIST development created WAIS, Wide Area Information search, the precursor to WebCrawler and Lycos.
    NIST invented the scanning tunneling microscope [nist.gov], without which the RAM your computer is running could never have been designed.
    NIST research was the first to show that the universe has parity [nist.gov]

    NIST's Information Technology Laboratory [nist.gov] has contributed open research to America about IT, including a lot of open source software. Sure, it doesn't show a profit, so Congress can call it "waste" - but I know that you know that we all use it.
    get [nist.gov] a [nist.gov] goddamn [nist.gov] CLUE!!! [nist.gov]

    Or someone will beat you with the clue stick [nist.gov].

    NIST has a solid history of debunking junk science and provide nobel-level physics and science research. If you are reading this on a laptop, your screen's interface was designed at NIST. The sad part is that I can barely remember all their contributions to science in the 5 minutes i'm taking to write this.

    But I shouldn't have to. Why don't we tear down the space shuttle and use it to build houses?

    Get your stupid troll out of my face.
  • with their embrace and extend philosophy, it'd become the National Kilogram 'and a half'...

    (Hmmm... I smell an off-topic mod coming...)

  • but instead of spending X millions on a bunch of bs, they should look to consolidate it all


    Put it this way:

    but instead of spending X millions of programmer-hours, we should consolidate on one kernel


    Competition is good. Sometimes it may seem inefficient, but in reality that redundancy is insuring that we don't get stuck at some local maximum and truely go for the global maximum.
  • thats funny. A 50 meter tunnel filled with methane/air. That successfully makes a 50 meter CANNON!

    Sounds sort of like the goatse guy.



    --
  • It's worrying to hear that advanced scientific projects (ie: NASA Mars probe) are not using metric already though.

    As far as I was aware they were. It was only the PR dept that converted everything to imperial. Of course most of the rest of the world gets it converted back to metric going through a form of chinese whispers, Except of course in china where presumably the whispers would make sense. Of course given current events there is evidence to suggest that they have their own problems when it comes to agreeing on measurements, most notably at the moment would be distance.

  • ""You could have lunch in your modem," Stanford says.
  • Just a minor point -- kilogram is not a unit of weight, it's a unit of mass. Weight is a force, and is measured in Newtons (in SI) and so is dependent on gravity.

    Interestingly, Webster's claims that a pound is "any of various units of mass and weight", which makes it ambiguous. It also defines it in terms of kilograms, making it a mass. OTOH, a common measure of pressure is pounds per square inch, implying that pounds measure force. I assume that 1 pound of mass weights 1 pound at 1 g. :)

    -Puk
  • maybe a little off topic, but did anyone else get slightly annoyed by the condescending attitude towards the scientists and "eggheads" while the glass-blower was made out to be an artist and "maveric" etc. etc? Stupid mainstream media.. *grumbles*
  • Cartman, what the hell are you talking about?
    England has left-side traffic. Only England, mmkay?
  • Sorry, i meant that England is the only EUROPEAN contry with left-side traffic. Beg your pardon, dear Sirs.

  • by Thomas Miconi (85282) on Thursday April 05, 2001 @01:29AM (#314044)
    While your post is an obvious piece of shameless trolling, and despite Betcour's remarkably accurate answer, I'll still add a few comments:

    1. Still rely on the French to define your unit of mass, eh? (Rusting, other chemical readtions with the block. Bye bye perfect reference!) And the meter being the distance from the North pole to the equator thru Paris divided into 10,000,000 parts? Yah, that's real accurate
    The kilogram is the only unit that is still defined after a physical reference: a 2001-like monolith of platinium covered with iridium, located at the Conservatoire national des arts et metiers [www.cnam.fr] There are other equivalent "reference kilograms" worldwide that are similarly amagnetic and insensitive to rust or corrosion. The metre is the distance covered by a photon in 1/299 792 458 second. The second itself is based on transitions between two states of the cesium 133 atom. More information at the Bureau International des Poids et Mesures [www.bipm.fr] (Yes, there is an English version :o)

    1. And why do people state "weight" or "thrust" in kilograms? Why not Newtons?
    Because people (including me and you) are morons, so they use a MASS unit to describe WEIGHTS and FORCES, or use WEIGHTS and FORCES to determine MASSES. This is totally stupid if you're an angst-ridden physicist living in an ivory tower somewhere in the Kalahari desert. For the rest of us, since G is a constant in any given place (there may be slight differences between two different places), the confusion is acceptable, because measuring something's WEIGHT is still the easiest way to determine its MASS. Could you tell me of any practical mass measurement method (for solids) that does not rely on weight comparison ?

    1. Why do we still ask for a "pint of ale" in the UK?
    First, because Brits are drunkyards. Personally I always drink beer by the glass (half-pint) ;o)

    Second, because you (or at least your ancestors) blatantly screwed the French. In 1875, France accepted to leave the international zero-meridian to the English (Greenwich instead of Paris), because the English promised to adopt the metric system in return. Yet another shameless lie from the Perfide Albion ;o)

    1. And if base 10 is so l33t, where is metric time? Base 60? Why stick with millenia old numbering from Babylonian times yet praise base 10 everywhere else
    There is no such thing as "metric time". The second was invented by astronomists long before the metric system. The idea to "pack" the second with the metric system (metre, kilogram, litre) in order to have a coherent measurement system is (c) Gauss (1832). And this is how the International System was born.

    And, by the way, there is no base-60 stuff in the International System itself. The only time unit in it is the second, period. If you were to speak in pure IS units, you would talk about kiloseconds and hectoseconds (just in the same way as you talk about milliseconds or microseconds). Hours and minutes are pure legacy stuff, and are not part of the IS - they're just here because it's easier to divide the day in 24 hours than in 86,4 kiloseconds.

    Thomas Miconi
  • Don't forget the Seychelles and other surrounding Islands...
  • For all of you engineer geeks looking to do this kind of cool stuff, you might want to check out the Underwriters Laboratories [ul.com] (yeah, the UL on the back of damn near every bloody device that uses electricity :)). You know those videos you see of a robotic arm slamming a refridgerator door over and over, or dudes in lab coats and goggles watching a laser, or even a building getting torched to test the sprinklers? Probably taken from the UL. Beats working for a government agency anyhow. ;)

    Deosyne
  • should we drive on the left side of the streets too?

    I think Germany was driving on the left until 1912 or thereabouts - just before WW1. Most places used to drive on the left; Napoleon made driving on the right law and the change filtered through. In some cases it took longer than others (certain north European countries I think).

    Back to the metric system: the UK changed officially from Imperial to metric over 20 years ago, but the road signs still show miles instead of km. Everyone learns metric in school though - to the extent that most don't know the exact relationship between the old units.

    The easiest way for America to change over is to change what is taught in schools first, then start placing both types of units on consumer products. When that generation has grown up, there will be no need for the old units and they can be dropped.

    It's worrying to hear that advanced scientific projects (ie: NASA Mars probe) are not using metric already though.

    -- Steve


  • According to this article [technologyreview.com], NIST will be constructing a high-tech Advanced Measurement Lab in the near future to combat the problem of vibrations.

    "If the AML lives up to its design specs when its doors open in 2004, its steadiest laboratory surfaces will move less than a picometer (a trillionth of a meter) per second."
  • The National Research Council Canada [www.nrc.ca], through it's Institute for Measurment Standards [www.nrc.ca] does the standard clocks/mass measurements for all the Canuck's out there.

    Available in both Canadian official languages of course!

  • Americans are such idiots. (Score:1, Informative)

    Hahaha

    ---

  • Similar institutions in other countries include Canadian Safety Administration (CSA)

    Nitpick... that would be the Canadian Standards Association (CSA).

    ---

  • annoyed by the condescending attitude towards the scientists and "eggheads

    Actually, while I thought they did go a bit overboard with praising blow boy, I got the feeling like they were referring to those nerds and eggheads with a deserved awe and respect - which those people deserve, I'm sure, otherwise they wouldn't be working there.

    ---

  • LMAO!
  • The real test is, could this press close up the Goatse.cx guy's asshole?
  • I'm Brasilian, moved to the US some 5 years ago.

    Ounces, quarts, etc. also delude me.

    But Farenheit? Jeeeeeeeeeeesus!

  • should we drive on the left side of the streets too?

    You may find this interesting... It spells out what side of the road each country drives on (66% of the world's population drives on the right).

    http://www.travel-library.com/general/driving/driv e_which_side.html [travel-library.com]

  • Yes. That's correct. I forget what a pint is in metric but it's 537ml or something like that. It's something that you also have to take into account when comparing gas prices between the UK and the US (though the price in the UK is still many times that in the US and I still raise a wry smile when I hear Americans complaining about their gas prices).

    I mean, $20 to fill up my minivan? My car I had in the UK would take 60UKP to fill (~$100).

    Rich

  • that "a 6 foot aluminum sphere with microwave plasma lamps" can "occur daily". That scares me.

    Someone please mod slashdot so that articles get proofread before being submitted. If nothing else, could Roblimo (a real journalist) at least go and slap these guys around a little bit.

    Rich

  • A pint's a pound the world around

    1 UK pint=20 flOz, 1 US pint=16 flOz. An ounce is the same both places and so is an lb (or as near as dammit).

    So I guess that puts the lie to that. Unless you use the American Standard Definition of "The World" which means anything bordered by Canada,Mexico, the Pacific and the Atlantic.

    Rich

  • should we drive on the left side of the streets too?

    Have you forgotten that your nothern neighbours (Canada, you know, where the igloo's are) having been using the metric system and driving on the right for a long time.
  • 320% ratio, or, 3.1:1 AKA 76.2% methane
  • It's somewhat interesting that most of the standards developed out of a requirement to keep commerce and business flowing and moving, with emphasis placed on commonality and uniformity. Now so-called 'standards' actually *compete* for business. This suggests to me that the critical industries, where actual material is moved as commodity, require real, common, physical standards, and that all the other 'industries' are really just using standards as another term for product. No wonder certification exams are so hard to standardize.
  • I visited NIST in the fall as part of a conference, and I didn't see anything wasteful at all. Consumer advocacy is very important. We are lucky to have things like the FDA.

    Their efforts in computer science have been very good. One of the main things that they do is provide evaluation metrics and facilitate competitions/evaluations for different tasks. Often times it is hard to really define metrics for software evaluation (cf all the benchmarkings for speed). This is something that should not be left to the manufacturer's (which is why all these non-independent evaluators tell us how slow Linux is compared to Windoze). By defining a task and then performing the evaluation on the software, NIST acts a real independent evaluation. This is the type of role they play in many industries. I'd rather have NIST doing this than relying on the marketing people.

  • Although the original metric system was based on pure water(the calorie was defined in terms of heating water), it really has nothing today with today's system which relies on much more precisely measureable quanitities. And actually, the real basis of the measurement system was some very bad measurements of the earth which they attempted to divide up evenly into the meter. This was then combined with the second (which is a very arbitrary division of time). This distance and length measure were then used with water to get standards of length, energy, and temperature. Now, for example they used fixed wavelengths from a band in the Cesium spectrum to measure length, and atomic decay times to measure time (they should use a pulsar instead). One of the points of the article is that we are using an actual kilogram and comparing things to it (which is very primitive). One can also imagine that the real international standard is not very similar to the US one, at least at the precision we can now measure things at (considering it is over a hundred years old). There wasn't any information about this in the article.

  • When I worked for this synthetic diamond manufacturing company, that is where I got to see some serious pressure. They would put these little boxes of graphite into these huge 6 cylinder presses and squeeze them into solid diamond. I'm not sure exactly how much pressure it was but I heard that one of their competitors had a malfunction at one of their plants in France and one of their presses broke. The release of pressure was so great that it sent one of the hydraulic cyclinders clean through their factory wall and into an adjacent building. Also unfortunately, the press operator was standing right in the way of the projectile, he was instantly killed.

    Nathaniel P. Wilkerson
    Domain Names for $13
  • US Synthetic in Provo Utah, they have since moved to Orem Utah. Yes, I worked there for some time in R&D and also as a press operator.

    Nathaniel P. Wilkerson
    Domain Names for $13
  • I wonder ifthe physics BS I'm about done with will be enough to get me anywhere near the door. Probably not. It's a good thing I like the job I have now (sysadminning.. yum), because my degree is going to be pretty worthless. Why didn't someone tell me that when I started it?
  • HK and indonesia as well

    s'pore as well i think

  • That may very well be why NIST (formally known as National Bureau of Standards) is under the Department of Commerce.

    DanH
    Cav Pilot's Reference Page [cavalrypilot.com]
  • That is not a mental image I will treasure for my dotage.
  • Trust me not to proof read. It was 20% methane. The danger level is considered 4% from memory and a highly impressive explosion can occur not long after that. 5% maybe? Been a while since I got the run down, but be that as it may, the margin of error in a coal mine for methane levels is quite small, so I'll take your word for it. Some of the work they did in this gallery in the years later was the testing of flash suppessors and water baffling to stop the flame fronts that accomany a mine explosion. Also, a flash unit for a camera that could be used in highly explosive enviroments, that would also survive huge explosions. Even tho it seems obvious, they discovered that the most damage is not caused by the initial explosion, but the shockwave and air being shoved down the tunnels, as well as the debris being licked up and hurled. Enough to turn a 50 ton mine truck to scrap (source - Appin mine disaster, 1978 - now the photos from inside that mine have to be seen to be believed. Machinery in the tens of tons range just thrown up shafts like toys) The explosion gallery advanced the work in explosive knowledge to quite a degree and also to Fuel Air Explosives. Unfortunantly, I dont think it's in operation at present Residents of the area kept complaining. Sadly. This is one impressive example of destructive testing that has helped save people's lives.
  • by Darth Turbogeek (142348) on Wednesday April 04, 2001 @08:53PM (#314073) Homepage
    The Londonerry Occupational Health and Testing Centre, Richond NSW, Australia. It's a seriously cool place. The best place is what is called the Explosion gallery, where they simulate mine explosions. It is a 50 meter tunnel, which on it's forst test firing in 1979, was filled with a mix of air / methane to a ratio of 320% methane. This was before they knew exactly the power of mine explosions. They worked out they would need a ventilation fan for clearing the noxious gasses after the test firing, so they placed a 3 ton fan at the gallery entrance.

    The video of the event went a bit like this.... show the bushland at the tunnekl entrance, a rumble and then a flash and then... BANG!.... and pieces of fan ripped the trees to shreds for 50 meters. Decorated other trees with metal bits for 100's of meters. Oh man, it's an awesome video. Also is a real eye opener to see the sheer power of an uncontrolled explosion.

    Other interesting items are a full sized mine gallery to test fire fighting inside a mine, a cable destruction tester (up to 50 million newtons - a 5 inch steel cable breaking can punch holes thro 3 inch steel), an electrical destruction test lab, an engine dyno rated to 5000 hp and some serious computing grunt.

    Great place... especially when you know the guy who runs the place.
  • How about a 6 foot aluminum sphere with microwave plasma lamps called the 'Black Ball of Sunlight' to check that new polymer for photodegradation?

    I wanted to check that new polymer for photodegradation, but I was blinded instantaneously when I first saw the aluminum sphere in question.

    (2:30 am...just finished modern physics homework...mind rambling)

    ---
    The AOL-Time Warner-Microsoft-Intel-CBS-ABC-NBC-Fox corporation:
  • Would the sphere be abel to cook anything like a Thanks Giving turkey?
  • As far as I know, the 2 biggest presses in the world are located 1 in the former Soviet Union, and one in Bldg 56, Denver federal center. It is Part of the Bureau of Reclamation lab. I've worked there, and at NIST in Boulder. (the atomic clock is cool.) The Press at the BOR stands head fully raised 50 feet, and has a head about 15 by 15 feet. The operating pressure is somewhere about 5M newtons. One of the most impressive things I have ever seen in action. I've seen 12"x12" lumber used as "stickers" against the head during a press pour water out like a sponge. And this is cured lumber. They also have tons of other stuff there, a low ambient pressure chamber for cavitation testing, a 100% humidity room, exact models of riverbeds that fill a 100'x50' room to test erosion. Just fantastic.
  • Or just go to Time.Gov [time.gov] It's a tid bit easier.
  • The only thing that is stunning is how you waste time replying to the posts of those who wasted time replying to the posts of these idiots.

    Oh, wait.

  • by Sir_Real (179104) on Wednesday April 04, 2001 @08:29PM (#314079)
    Do they have a standard BlueTooth spec there? It seems some folks are just estimating. ;)
  • Um, angular measurement?

    Um, radians?

    ---

  • They got a homepage [nist.gov] too with a nice organizational chart [nist.gov] to give you an overview.

    Don't dare to mod me up!
  • by unformed (225214) on Wednesday April 04, 2001 @08:32PM (#314091)
    Have a 40 foot structure you need tested to 12 million pounds of pressure?

    yeh - the white house, and i'm sure that the results will benifit humanity :)
  • Given the problem with NASA and that we are truly going into a century of science. The USA needs to move to the metric system. It may take 25 years but it worth it. The US need to stop thinking they live in a bubble.

    should we drive on the left side of the streets too?
  • First of all, I don't want to see any quotes about jeopardizing "our fiscal well-being" from people who support a 1.9 trillion tax cut.

    Imagine if corporations were allowed to have any standards they wanted: weights, times, measures. I'll give you a hint: think "Web Browser Incompatibilities". Now imagine if that were the situation with real products...

    I bought this "Netscape Grade A Fancy Ketchup", but it turned out to be a green gelantinous substance made entirely from Coal Tar extract. So I bought some of the store brand "Microsoft .Ketchup," which was nice and red, but turned out to be made from beets and water...

    Thixotropic substances aside, your remark that the NSA should do our crypto standards for us makes me think that you must work for the NSA. According to Applied Cryptography, the NSA has stated (off the record, of course) that if it had known that the NBS (NIST) was going to make the algorithm public, it wouldn't have allowed DES to become a standard. So unless you like all of your crypto implemented in hardware on tampler-proof chips, I suggest you support your friendly National Standards Committee.

  • Now hopefully individuals from Microsoft, and several other large organizations, will read that article and finally understand the critical need for solid standards. It's a shame that there really does not exist a coherent standards body in the software world that has the breadth and respect held by NIST. I often wonder how much advancement is being held back or hampered by the constant pissing wars between companies regarding standards. Possibly I'm looking at it from the wrong perspective, but to me it seems the current systems aren't working in our best interests.

    Just thoughts.
  • filled with a mix of air / methane to a ratio of 320% methane.

    320%? The OSHA defined upper explosive limit for methane in air (meaning a mixture that's too "rich" to ignite) is 95%. 100% pure methane will NOT explode or even burn. But as little as 5% methane in air will explode, and I'm presuming you meant 30% (or 20%, or maybe 32%) methane in air, which will explode quite nicely with the results you described. It is commonplace to calibrate methane detector meters used in mines with a standards lab traceable mixture of 2.5% methane in air, which is too "lean" to ignite, but is high enough to set off the alarm on the meter.

  • by ScottBob (244972) on Wednesday April 04, 2001 @10:18PM (#314103)
    Actually, if destroying things for research is your opiate of choice, the Underwriter's Laboratory is the place for you. They zap, burn, smash, and thrash everything that gets the UL stamp on the bottom. From torture testing blenders to smashing TV screens, all is done to ensure consumer safety, and stand behind the manufacturer in case of lawsuit (Consumer: Your extension cord shorted out and burned my house down! Manufacturer: What did you have plugged into it? Consumer: A toaster, a microwave oven, and a George Foreman grill. Manufacturer: Sounds like you exceeded the UL recommended safe wattage load. Judge: The manufacturer is not liable for your damages. Case dismissed. (Gavel slam)). Similar institutions in other countries include Canadian Safety Administration (CSA) and Council European (CE).
  • I believe that resides at 1600 Pennsylvania Avenue. Dubya just recently visited Mexico for a "summit" after all. Ahem.



    If you love God, burn a church!
  • by Markoff Chaney (256107) on Wednesday April 04, 2001 @08:39PM (#314109)
    --NEWS BULLETIN--

    National Kilo stolen, replaced with precise kilo of China White in daring Indiana-Jones style robbery.

    The Mgt.
  • Could you tell me of any practical mass measurement method (for solids) that does not rely on weight comparison ?

    A company named K-Tron once made table scales which measured mass directly by measuring the change in resonant frequency of the entire platform/load cell assembly. This was highly nonlinear and each load sensing element was supplied with an EPROM describing the characteristics of its particular vibrating wire.

    These babies were amusing when they broke, because they would display seriously counterintuitive and nonlinear responses as you added test weights to them.

    And oh, this was quite an article. Working in the scale industry as I do, I quite appreciated it -- thanks, /. editors!

  • .. or something out of a dilbert episode
  • Or maybe misrepresented on my original post so here goes...

    yes encryption IS a good thing for people like NIST to put resources into. You need people at the top of the field, and it helps that the organization's interests fall right in line with having an open, secure encryption system.
    Agreed, but lets take a quick look at some of the branches of government doing the same, when one should be enough. Why can't one agency focus on this? Isn't NIST supposed to be the standard?

    Sandia researchers develop world's fastest encryptor [sandia.gov]

    ORNL Helps Develop Electronic Notebooks [ornl.gov] (read article to see crypto stuff)

    GRIP -- Gigabit Rate IPSec [darpa.mil] (Army)

    Cancer research [cancer.gov] (I never knew cancer genes needed encryption)

    WING [darpa.mil] (DARPA)

    NASA [nasa.gov] (why can't they look to NIST?)

    Key Agile ATM [darpa.mil] (DARPA)

    And theres a slew more. I agree that government should promote better standards, but instead of spending X millions on a bunch of bs, they should look to consolidate it all, which is what my main post should've stated I guess. Some of this so called research, or development never even sees the light of day due to timing situations. One part of government may intend to develop and deploy something, but it won't always happen, meaning all that money used for those projects are now gone, and they're left to ask for more money for some new project, never using their own resources to see if another agency can assist them.

  • Competition is good. Sometimes it may seem inefficient, but in reality that redundancy is insuring that we don't get stuck at some local maximum and truely go for the global

    OK... I won't dig too deep into this... Its one government we're talking about, and the NIST, is supposed to be the definitive source for standards... Not the NSA, not DARPA, not any other branch of government. So who is government competing with locally when they compete with themselves? Thats even more reason to point out the wasteful spending.

    Thats like Microsoft developers in the WindowsNT department creating another version of Word to sell as a Microsoft product named... Word and you don't see a problem with this?

  • by deran9ed (300694) on Wednesday April 04, 2001 @09:04PM (#314116) Homepage
    NIST also has a huge budget [nist.gov] thats been quoted to be wasteful spending at times by congress themselves.

    This legislation includes $535 million in pork-barrel spending. This is an unacceptable amount of money to spend on low-priority, unrequested, wasteful projects. Congress must curb its appetite for such unbridled spending.

    Pork-barrel spending today not only robs well-deserving programs of much needed funds, it also jeopardizes social security reform, potential tax cuts, and our fiscal well-being into the next century.
    complete referendum [senate.gov]

    In fact I recall I think it was 20/20 or 60 minutes which had an article where researchers were being paid high salaries to test the flow of ketchup (catsup/ketsup) and if it was thick enough for the American market.

    The episode went on to document millions of dollars gone to waste over some "trivial" (*cough* stupid *cough*) programs with NIST being on of the top sectors in gov. Shouldn't this money be used for useful purposes such as creating new jobs, housing, drug rehabilitation versus incarceration, etc., or am I being a troll because I find a problem with millions being spent to make sure my ketchup is thick enough?

    Now not to troll even longer, but I always thought the NSA handled this... or at least they would have the most input into any of the things related to security....
    enhance digital information security by publishing an advanced encryption standard and guidance for federal agencies on its use; by extending the public key infrastructure testbed to support industry development of interoperable digital signatures and encryption applications; and by developing, extending, and disseminating standard reference guidelines for emerging biometric authentication techniques;
    But what about the next one, shouldn't this be left to companies on their own to develop their own programs to meet their own needs, or is this something that just sounds good enough to push for more funding...
    support business use of electronic commerce by developing and disseminating a software translator that will convert a company's internal dictionary of product terminology into the industry-standard format, thus enabling engineers and designers to compare products and check their compatibility.
    (above taken from NIST [nist.gov])

    How is government affected by someone's product that may not be compatible with anothers? Or let me rethink this, what defines an industry standard format, and according to whom, last I checked, I've never read anywhere that Microsoft had to make its *.doc files compatible with anything because of regulation.

    Surely someone can regulate what constitutes a neccessity, but why not branch some of these things to academia, where things are always revolutionary changing constantly to keep up to date, as opposed to following standards set eons ago. Government can cut budgets by passing some of these tasks to colleges, then pay the universities to keep track of this at the fraction of a cost, keep students excited about helping government, and saving us all some money.

    I know for a fact many students would love to delve into this, especially if it'd help their tuition go down slightly, while improving standards in the U.S.

    Ghost in the shell [antioffline.com] (hiding your data)
  • how many ounces weight a gallon of water exactly? "A pint's a pound the world around." A gallon of water weighs about 8 pounds, a pint is one pound, or one ounce (liquid) water is 1 ounce (weight). Of course, this depends on the temperature and purity of the water -- but so does the 1 liter water masses 1 kg relation in the metric system.

    But I agree that the English system is ridiculous. At least there is only one definition of kilogram or liter, as compared to several "gallons", two "pounds", two "ounce" weights... Even with the American standardization upon one particular set of English units, it's still a lot harder to work with than metric.

    There are two exceptions: time and temperature. With time, we're still using the Babylonian system of base 12 & 60 -- and because we do have to divide up the day by other ways than 2 and 5, I don't think it can be changed for the better. (Also, redefining the second would invalidate whole books of physical constants). For temperature, now that we can precisely measure 0 K, scientists and engineers ought to be using the Kelvin scale -- most calculations using the Celsius scale require either subtracting two temperatures or adding an offset which actually converts to Kelvin. But the Fahrenheit scale has some real advantages for ordinary life: 0 to 100 F nicely defines the range from really cold to really hot for humans, and covers over 90% of temperate zone temperature measurements. The Celsius scale is rational only for chemical reactions in water (including cooking).
  • It seems to me that your main beef with the metric system is that everything is arbitrary about it. I've got bad news for you: the world is arbitrary. I could invent a measurement called a Fnord that would be the length from my foot to my bed (right now), and it would be equally valid. That's the entire point of measuring units - to take somthing that's totally arbitrary yet needs to be the same everywhere, and standardize the arbitraryness of it. That's why my Fnord isn't a real mansurement - beause it's not regular (my foot has moved since I wrote the above) and no one knows about it.

    As to the benefit of the metric system over the Imperial/UK system? It's dead simple. Take one basic word, and throw on some prefixes to get the scaled-up or -down units. And conversion between units is a matter of playing with ratios of ten that can be done on one hand by adding and substracting zeros (the factor-label method, my chem teached called it).

    The metric system is not inspired by god (as you seem to infer it is), nor it is perfect (I still meausre my heigh in feet/inches, but it is significantly simpler than anything out there.

  • One thing I really like about the International Standards; they're prepared to change.

    The second *is* now defined in terms of oscillations of a particular isotope of a particular type of atom, instead of being a tiny fraction of the day-length, because we can measure those oscillations more accurately than we can measure the length of a day.

    It's nice that this can be measured in any laboratory around the world. If/when gravitational effects become detectable, they are calculable; the correction need not be as precise as the original measurement, because it is such a small effect. And General Relativity *is* verified at that kind of level.

    The metre was once defined in terms of a standard bar, but is now defined in terms of the distance light travels in a second, because that's what we can measure most accurately.

    The Kilogram - is a lump of metal, because we can preserve and compare the mass of that lump of metal to greater accuracy than we can measure the mass of anything else. When that changes, the standard will be changed. Until then, nothing can be measured more precisely than that, so it doesn't matter.

    Incidentally, it has been predicted that the 'lump of metal' will be replaced with a standard based on the mass of a certain number of atoms - in other words, a standard based on Avogadro's Number.

    Yes, in some sense the units we use are arbitary. There exist, however, units which are *not* arbitary; units which are defined simply, solely, and entirely on the physics of the universe itself. Using these units, no physical equation requires any constants (apart from simple numbers like 2 and pi).

    The problem with these units is that they are so incredibly, unworkably small! People don't want to measure distances in terms of quantities many times smaller than the diameter of an electron. Units like yards and inches came from the length of certain parts of the human body (a fine standard indeed!). The units we use are those convenient to the problem.

    Rachel
    Nuclear Physics PhD Student
  • My favourite explanation for the left/right thing is that, if you are right-handed and on horse-back, you ride on the left of the road, so your sword hand is ready to defend yourself against attackers.

    If your country goes through a revolution, it pays not to look like a rich-guy-on-horseback-with-a-sword, so you start walking on the right instead.

    Thus, countries that have gone through revolutions are likely to drive on the right (France, US), countries that have had continuous government are likely to drive on the left (UK, Japan)

    On the metric/Imperial thing (pounds, feet, pints etc. are called Imperial in the UK, where we also have cool measurements like stones, furlongs and drams), the Imperial stuff is great for everyday estimating. An inch is about the length of the last joint of my thumb, a foot is about the same size as my foot (wow!), a yard is a long pace, a mile is about 1000 normal paces, and a pint glass fits nicely in my hand.

    But for anything technical or scientific... well, Imperial just doesn't cut it. In metric, everything is keyed to the metre (which is defined arbitarily - I believe these days by the speed of light in a vacuum), and any idiot can multiply/divide by ten. 1 litre of water weighs 1 kilo. That's just, just.... so simple!

    Anyway, both systems work, there's no need to throw one out in favour of the other. Just choose the one that fits the situation.

The only difference between a car salesman and a computer salesman is that the car salesman knows he's lying.

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