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The Changing Definition Of 'Kilogram'
DrLudicrous writes "The NYTimes is reporting that the platinum-iridium standard mass for the kilogram is shedding at an appreciable rate -- at least compared to other reference masses. The Pt-Ir cylinder is kept in France, and measured annually, and the slight discrepancy is important because the kg is an SI base unit- thus other quantities such as the Volt are based on it. A new standard is being sought- the two frontrunners are counting the number of atoms in a perfectly spherical single crystal of silicon, and another technique uses a device known as the Watt balance."
Hey I live in America you insensitive clod! (but then again I alawys want to know how much they are lifting on Strongman Competition).
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Why exactly does it have to be measured annually, and why should I care if it detoritates? Anyone care to enlighten me?
Yay, I wiegh less!
However, I don't know by how much, since I don't live in bloody England.
Everytime she steps on the scales...I would tell you what it was defined as last week, but kids may be reading this.
Would have been nice to link to a site that doesn't require name, rank, serial number, and blood type to read.
you can't even trust them with a bar of lead!!
i'm not gaining weight, the kilogram is losing mass... so really, i stay the same weight, and they need more units to weigh me ;-)
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
I'm surprised that no one has tried until now to create a standard for the kilogram that could be repeated easily like atomic measurement of the length of a meter and the computation of a second of time based on the resonance frequency of a caesium atom.
If they succeed, we can get a reference standard for a kilogram that can be easily generated for scientific research.
Nope. We dont use Volts either. At least not the same kind of volt everyone else does, apparently. So, if the kilo is shedding causing them to recalibrate the volt, is my electric bill growing or is it shrinking? Answer that and I will tell you my opinion on the matter.
Why couldn't they just take it down the shops and measure it against, say, 1kg of carrots or a kg of sugar?
Never fight naked, unless you're in prison...
...just define a kilogram in terms of 'x' number of Joules. Since c is a defined constant, then this would give you a constant mass.
Here is a site that gives some reasons why the are thinking of replacing the standard: http://physics.nist.gov/News/TechBeat/9501beat.htm l.
No registration necessary
The problem with the single crystal of silicon method, a few years ago, was that there were all these lattice vacany defects cropping up. The formation of such point vacancies is so entropically favoured that I don't think they can ever eliminate them...
I don't know if this happens anywhere else in the world, but in Australia, 1MB = 1000kb for an ISP.. Tel$tra thinks 1MB=1000KB, but 1KB=1024B.. Go Figure...
Yes, it's the asparagus. There's a compound in it which causes your urine to smell badly.
The effect's well known to all those who enjoy water sports...
It's not my ass, it's just that the units are getting incrementally smaller. Ho ho! It's not me. *dances*
Damned inreliable measure standards. *shakes fist*
Informatus Technologicus
Huh? The English aren't even using their own system now.
Well according to the latest SI and IEEE standards, 1 MB = 10^6 bytes, 1 MiB = 2^20 bytes
You'll find hard disk manufacturers use it too.
Does this mean we have to upgrade the firmware in our scales every year?
No, Beowulf clusters can't imagine in Soviet Russia.
My question is, how do they measure it? Using a non-decaying meter stick? How do you measure the definition of a measure?
I for one welcome our new SCOviet Russian overlords to whom all our base are belong.
We don't have any fancy platinum masses to decay, just gets you a hogshead and a rod, and you're set!
how exactly do they derive volts from kilograms?
-Then maybe america should move out of the dark ages sometime.-
But honestly its (the kilo) as arbitrtary as any other unit we have come up with to describe reality (red, one second, a kilometer) so why rewrite the bible as it were and change something like this?
I know the implications could be staggering, but why not chalk it up to having a leap year and other silly things about our units of measurment.
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Scientists Struggling to Make the Kilogram Right Again
By OTTO POHL
RAUNSCHWEIG, Germany -- In these girth-conscious times, even weight itself has weight issues. The kilogram is getting lighter, scientists say, sowing potential confusion over a range of scientific endeavor.
The kilogram is defined by a platinum-iridium cylinder, cast in England in 1889. No one knows why it is shedding weight, at least in comparison with other reference weights, but the change has spurred an international search for a more stable definition.
"It's certainly not helpful to have a standard that keeps changing," says Peter Becker, a scientist at the Federal Standards Laboratory here, an institution of 1,500 scientists dedicated entirely to improving the ability to measure things precisely.
Even the apparent change of 50 micrograms in the kilogram -- less than the weight of a grain of salt -- is enough to distort careful scientific calculations.
Dr. Becker is leading a team of international researchers seeking to redefine the kilogram as a number of atoms of a selected element. Other scientists, including researchers at the National Institute of Standards and Technology in Washington, are developing a competing technology to define the kilogram using a complex mechanism known as the watt balance.
The final recommendation will be made by the International Committee on Weights and Measures, a body created by international treaty in 1875. The agency guards the international reference kilogram and keeps it in a heavily guarded safe in a château outside Paris. It is visited once a year, under heavy security, by the only three people to have keys to the safe. The weight change has been noted on the occasions it has been removed for measurement.
"It's part ceremony and part obligation," Dr. Richard Davis, head of the mass section at the research arm of the international committee.
"You'd have to amend the treaty if you didn't do it this way."
That ceremony has become a little sorrowful as the guest of honor appears to be, on a microscopic level at least, wasting away.
The race is already well under way to determine a new standard, although at a measured pace, since creating reliable measurements is such painstaking work.
The kilogram is the only one of the seven base units of measurement that still retain its 19th-century definition. Over the years, scientists have redefined units like the meter (first based on the earth's circumference) and the second (conceived as a fraction of a day). The meter is now the distance light travels in one-299,792,458th of a second, and a second is the time it takes for a cesium atom to vibrate 9,192,631,770 times. Each can be measured with remarkable precision, and, equally important, can be reproduced anywhere.
The kilogram was conceived to be the mass of a liter of water, but accurately measuring a liter of water proved to be very difficult. Instead, an English goldsmith was hired to make a platinum-iridium cylinder that would be used to define the kilogram.
One reason the kilogram has lagged behind the other units is that there has been no immediate practical benefit to increasing its precision. Nonetheless, the drift in the kilogram's weight carries over to other measurements. The volt, for example, is defined in terms of the kilogram, so a stable kilogram definition will allow the volt to be tied more closely to the base units of measure.
A total of 80 copies of the reference kilogram have been created and distributed to signatories of the metric treaty. The sometimes colorful history of these small metal cylinders underscores how long the world has used the same definition of the kilogram.
Some of the metal plugs were issued to countries that later vanished, including Serbia and the Dutch East Indies. The Japanese had to surrender theirs after World War II. Germany has acquired several weights, including the one issued to Bavaria in 1889 and the one that belonge
May 27, 2003
Scientists Struggling to Make the Kilogram Right Again
By OTTO POHL
B RAUNSCHWEIG, Germany -- In these girth-conscious times, even weight itself has weight issues. The kilogram is getting lighter, scientists say, sowing potential confusion over a range of scientific endeavor.
The kilogram is defined by a platinum-iridium cylinder, cast in England in 1889. No one knows why it is shedding weight, at least in comparison with other reference weights, but the change has spurred an international search for a more stable definition.
"It's certainly not helpful to have a standard that keeps changing," says Peter Becker, a scientist at the Federal Standards Laboratory here, an institution of 1,500 scientists dedicated entirely to improving the ability to measure things precisely.
Even the apparent change of 50 micrograms in the kilogram -- less than the weight of a grain of salt -- is enough to distort careful scientific calculations.
Dr. Becker is leading a team of international researchers seeking to redefine the kilogram as a number of atoms of a selected element. Other scientists, including researchers at the National Institute of Standards and Technology in Washington, are developing a competing technology to define the kilogram using a complex mechanism known as the watt balance.
The final recommendation will be made by the International Committee on Weights and Measures, a body created by international treaty in 1875. The agency guards the international reference kilogram and keeps it in a heavily guarded safe in a château outside Paris. It is visited once a year, under heavy security, by the only three people to have keys to the safe. The weight change has been noted on the occasions it has been removed for measurement.
"It's part ceremony and part obligation," Dr. Richard Davis, head of the mass section at the research arm of the international committee.
"You'd have to amend the treaty if you didn't do it this way."
That ceremony has become a little sorrowful as the guest of honor appears to be, on a microscopic level at least, wasting away.
The race is already well under way to determine a new standard, although at a measured pace, since creating reliable measurements is such painstaking work.
The kilogram is the only one of the seven base units of measurement that still retain its 19th-century definition. Over the years, scientists have redefined units like the meter (first based on the earth's circumference) and the second (conceived as a fraction of a day). The meter is now the distance light travels in one-299,792,458th of a second, and a second is the time it takes for a cesium atom to vibrate 9,192,631,770 times. Each can be measured with remarkable precision, and, equally important, can be reproduced anywhere.
The kilogram was conceived to be the mass of a liter of water, but accurately measuring a liter of water proved to be very difficult. Instead, an English goldsmith was hired to make a platinum-iridium cylinder that would be used to define the kilogram.
One reason the kilogram has lagged behind the other units is that there has been no immediate practical benefit to increasing its precision. Nonetheless, the drift in the kilogram's weight carries over to other measurements. The volt, for example, is defined in terms of the kilogram, so a stable kilogram definition will allow the volt to be tied more closely to the base units of measure.
A total of 80 copies of the reference kilogram have been created and distributed to signatories of the metric treaty. The sometimes colorful history of these small metal cylinders underscores how long the world has used the same definition of the kilogram.
Some of the metal plugs were issued to countries that later vanished, including Serbia and the Dutch East Indies. The Japanese had to surrender theirs after World War II. Germany has acquired several weights, including the one issued to Bavaria in 1889 and the one that belonged to E
--
http://nemilar.net - Not your grandmother's soup kitchen
the thing is shrinking, right? so they come up one year to measure its mass again.
"what's the mass there?"
"0.999999 kg"
"the mass is a fraction of itself?"
"yeah i guess so"
"ok then, so we shall redefine the kg to be an infinitely small mass"
"tres bien!"
"oui"
and instantly the volt follows, causing electrical havok worldwide.
to get around NY Times registration?
Since there is only one reference object for the kilogram, everything else is just a copy -- and even if it is a first generation copy, errors are bound to creep in.
The redefinition of the kg is long overdue, mad props to the scientists working on this.
When I was in school, I was taught that the standard method was to measure megs in base 10 for transmission (1000000 bits/bytes), and base 2 for storage (1048576 bits/bytes).
Pain in the ass to have to do the conversion back and forth... 1/2 the class took days to 'get it'
"Faith: Belief without evidence in what is told by one who speaks without knowledge, of things without parallel." - A.B.
nah .. they should throw out the whole kilogram concept and weigh everything according to a "library of congress".
eg. that woman weighes 2.36 libraries of congress.
I think I need a thesaurus and a dictionary
One nominee that is amusing is to have the basic unit of distance based on the speed of light.
One light nanosecond = roughly 11.1 inches, kinda close to a foot.
I remember how Grace Hooper used to pass out wires that were that long, just to make the point.
Any other nominees?
"It is a greater offense to steal men's labor, than their clothes"
And all this time I just thought I was just getting used to cocaine.
The dogcow says "Moof!"
Darn right! After all, it's easy enough to convert fortnights to stone with a Mayan calendar.
We're going to in the future eventually. It's inevitable.
I know it's 60 firesticks per 100 Watts, and 3000 Volts per staticy tomcat, but it might just be easier if we all just jumped in and switched to metric 144%.
I mean picture doing 100 on the highway! Wouldn't that be great? And dozens of future Mars landers would actually land on Mars, instead of digging ideal tree planting holes and landscaping future martian neighbourhoods. ("Zyphod! Incoming! It's the Americans!")
No more two sets of wrenches and lost sockets! Now you can have one set of sockets with half the sockets missing, instead of two sets of sockets with half the sockets missing. And no more asking for an 5mm and trying to make a 1 3/4" fit, rounding off the edges and carving a perfect turkey slice off your hand and gushing gallons of blood. It would be litres, which is less.
And you get to tell women that you, sir, are endowed with twenty-two centimeters of man!
Of course, the loss of the 25 cent piece will be a negative, since we'll have to pay for everything in dimes. But it's worth it dammit.
Seriously, we all know this is going to happen. When are we on board? Are we that stubborn?
The baby's fine -- please stop sending business cards.
Lou: So what is the name of the other balance technique device?
Bud: Exactly
And why is this sample in France deteriorating anyways? Don't they keep it in a vacuum (purged periodically with Helium)?
is a page describing the difference between weight and mass.
But for those of us who don't like to click:
I wonder why the standard is decaying. Seems like it would be one of three things:
1) sublimation
2) radioactive decay
3) desorption of surface films
Sublimation being metal atoms going directly from the solid to the gaseous state. Metals have extremely low vapor pressures, but maybe after 100+ years enough metal has evaporated to make a difference.
Radioactive decay could be from trace impurities of radioactive elements in the standard.
Finally, perhaps the original standard had a film of something adsorbed to its surface, and that film is slowly desorbing.
Basically you would have to keep the bar in a hermetically sealed vacuum where it couldn't accumulate any dust or outgassing from its container. This is probably why its 'losing' weight. Perhaps it had some fingerprints or other smudges on it that have eventually evaporated away.
-
There are only 7 base SI units (meter, kilogram, second, ampere, kelvin, and candela)
Sould, you're killing me! What's the seventh unit? Is it the mole?
I've never exactly examined the smell of my pee but I live on a lake I do a lot of water skiing during the summer... What's this strange pee you speak of? I am confused. Befuddled. Dildo in my butt.
Like duh. How else would you do it?
There used to be a custodian of the kilogram whose job it was to wipe the dust and oxidation off the mass with a chamois before it was used. It had to be done just right-too little pressure and the kg would have some stuff left on it and weigh more. He retired a few years back, so i wonder how it's done now. Also, apparently there had to always be two people to handle the kg, one to carry and another to catch it.
You are right about the imperial system being defined in terms of SI. However I find that where I am familiar with both the imperial and metric measure, the imperial one is usually easier to understand.
No mystery why. The imperial is just one of the many systems that grew over centuries in europe and the world to measure things that ordinary people actually use. The metric system was made up by a few revolutionary frenchmen over a shortish period and held hostage to a fetish about the number 10. Over time it has been updated only for very technical reasons.
Didn't see one of these yet (but of course there will be one posted right before I submit this...):
h tml?ex=1054612800&en=a5e16828b6cf309b&ei=5062&part ner=GOOGLE
http://www.nytimes.com/2003/05/27/science/27KILO.
One kilogram is equal to the weight of 1/256th of a VW beetle! Simple as that! Silly French.
Is there any physical reason (other than that small matter of cost ) that crafting a new kilogram (or more likely, gram) out of diamond would not be an ideal solution?
BTW, theNational Physical Institute has a FAQ on its Pl-Ir standard kilo.
I personly like the old idea, that a Kg is one liter of water, one liter = 10Cm^3. The article mentioned this was discarded because of the dificulty of working with water. Still, it has a lot of elegance, and links nicley with the concept of temurature.
"A language that doesn't affect the way you think about programming, is not worth knowing" - Alan Perlis
The only known quantity of Unobtainium (UB238) has gone missing.
The 1 kilo square block was being held in Brussels awaiting return to Brazil, where it was originally unearthed.
It was determined that the physical stability of the material was being affected by being moved from it's original location, that of being south of the equator. Investigators are anxious to reclaim the material in hopes of stabalizing it's rumored flux in mass. The UB238 was being packaged for transit, when it suddenly dissapeared from the shipping room counter. The rumor that it had created, and subsequently fallen into, a 'portable black hole' was discounted by investigators on the scene.
Once the Unobtainium is recovered, and returned to Brazil, it can be weighed and certified as a replacement for the Pt-Ir cylinder that is kept in France, and measured annually, representing the kilo standard for the world.
MPEG at 11.
It seems they should just reference the kilogram to a standard, such as x,xxx,xxx,xxx Si (28 isotope) atoms. This would eliminate the complications trying to build a standard, duplicate it and correct for earth's gravitational variations at the time and place of checking physical reference mass (not weight, to which the article alluded). Keep in mind the kilogram is a measure of mass, and not weight. That is why maintaining a physical standard requires correcting for gravity at the location's, time, elevation, tide, (add geophysical conditions, ad nauseum) of measurement.
If we are maintaing a physical chunk of alloy as the standard, it's time to decide on a more precise measurement, like we did with the meter long ago.
Oops. should be the National Physical Laboratory.
I really must get around to learning to read someday.
What has happened to the weight of the other ingots mentioned in the article?
Is the Oprah
I thought if they would "define" Plank's constant instead of measuring it, the kilogram would fall out of this. This is similar to how they now "define" what the speed of light is instead of measuring it.
Unless you're a hard drive manufacturer, in which case 10 gigs is in base 10. :-)
but what do i know, i'm just a model.
I know, I tried to explain to my wife that a megahertz is 1,048,576 times as painful as a stubbed toe the other day, but she didn't buy it...
Max Planck came up with an idea (in 1899!) for a system of measurement that really avoids all of these silly restrictions.
His idea: base all measurements of fundamental CONSTANTS like Planck length, c, etc.
The place where I saw this: www.planck.com.
several problems
1) ultra-pure water (which, amongst other things like really-hard-to-get, have an insane amount of surface tension, which means it's really-hard-to-work-with)
2) a container that is completely flat on all six sides (or five, but if only five, then you have to worry about below), and measured to atomic-precision dimensions
3) muniscus of the water
4) make sure there is no reaction between the water and surrounding container
5) make sure water does not evaporate
there are more, but I am gonna stop.
I have to say, if volt is really related to kg, then a volt can be represented in electorn-volt proportions, which then can in turn pump out the kg. but whatever.
I think my favourite SI unit is the Newton (unit of force)... holy crap, I just realized have no life.
The various prefixes -- kilo, Mega, Giga, and so on -- are very precisely defined SI prefixes that have been in common use in the sciences for quite some time now. In computing though, 1024 bytes was originally termed a "kilobyte" because it was very close to an actual "kilo" of bytes (1000 bytes), and so was a convenient term to use. In other computer-related disciplines though, in particular engineering, the correct SI usage prevailed, so your 128 kbps mp3s actually have 128000 bits per second, not 128 * 1024.
The big problem is that 2^(10x) and 10^(3x) diverge as x increases: 1024 is 2.4% more than 1000, 1048576 is 4.9% more than 1000000, 1073741824 is 7.4% more than 1000000000, and so on. So obviously the "close enough" thing is getting less and less true -- when there's a 10% difference between the two measurements they're not even close enough for everyday colloquial speech.
So the solution of both the SI and the IEEE is to reassert the original meanings of the SI prefixes (kilo = 1000, Mega = 1000000, etc.), but to add new base-2 prefixes in recognition of their usefulness in computing. These are kibi, Mebi, Gibi, etc. (basically the same as the SI prefixes but with the last two letters replaced by "bi"). Their standard abbreviations are the same as for the SI prefixes, but with a lowercase 'i' appended (so ki, Mi, Gi, etc.).
The conversion is obviously nowhere near complete, and irritates some computer people who don't want to change the terms we've been using for decades, but this seems to be the only really reasonable way of doing things. The only other two options are to either force the rest of the sciences to change to use the base-2 definitions (which is obviously not going to happen, and they got there first anyway), or to maintain the current ambiguity, which is also obviously undesirable.
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
Actually, the mass of an object is a measurement of the object's inertia. Also, weight is a measurement of force.
temurature: The contextual act of temuring water until it feels smooth to the touch.
Not to be confused with pemurature, which is commonly known as the feeling one gets when confronted with the undeniable stench of a rotting 'pemura' (Canadian Woodchuck), left to bake under the porch, during a long July afternoon in Toronto.
Is there a problem with the earth's gravitational pull? Fallout from the atomic wars?
What i've never understood is since the kilogram is the base unit why didn't they just call it the gram?
You can use a pound as a unit of mass simply by specifying that the context is Earth sea-level. In some sense "weight in a fixed gravitational field" and "mass" are equivalent concepts.
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
Well, c already defines the meter.
ReadThe ReflectionEngine, a cyberpunk style n
From the article:
Dr. Becker is leading a team of international researchers seeking to redefine the kilogram as a number of atoms of a selected element. Other scientists, including researchers at the National Institute of Standards and Technology in Washington, are developing a competing measurement system, based on the imperial system, which will be defined using a complex mechanism known as the watt balance.
Damnit! I thought that this is the chance to kill the imperial system, but those crazy americans are using the metric flaw in order to promote their inferior system!
It just furstrates me again and again..
(Lord It's Hard To Be Happy When You're Not) Using the Metric System - Atom and His Package
12 inches per foot, two pints per quart, why don't we make it easy?
The English system of measurement must relate to history.
We can use units of 10 and convert with ease
like all the other countries.
I am in command, yes I am taking a stand from this disease we must be free. good god!
You're drunk with your tradition that has no validity
well I'm intoxicated with sports in metrics come drink a deciliter with me
we want metrics
we want it now
we know we can win
I weigh 170 pounds that's 90 kilograms
see metrics can even make you thin
all cool things are in metrics for example here's just one
I've got my 9, well that's 9 millimeters, sounds cooler than my point two seventy inches gun.
The president will not exist
and they will call me communist
and call me scum
but its worth it Canadians will think we are smart or at least they will think we are not as dumb.
your tradition that has no validity
well I'm intoxicated with sports in metrics come drink a deciliter with me
we want metrics
we want it now
we know we can win
I weigh 170 pounds that's 90 kilograms
see metrics can even make you thin
the revolution is here we must overcome at last
as we symbolically stick their fucking foot up their fucking ass
guitar!
Your tradition that has no validity
well I'm intoxicated with sports in metrics come drink a deciliter with me
we want metrics
we want it now
we know we can win
I weigh 170 pounds that's 90 kilograms
see metrics can even make me thin
The posted article, while interesting, is wrong about the volt being based on the Kilogram. Since about 1990, the volt is defined to be the voltage applied to a Josephson junction that produces a frequency of 483,597.9 GHz. This new standard was implemented in order to get away from relying on 'artifact' standards (such as the Kg cylinder). One quick source page on Josephson junctions (which completely revolutionized the field of Metrology back when I was a calibration tech in the AF) is:/ squid.html
http://hyperphysics.phy-astr.gsu.edu/hbase/solids
If I recall correctly, the eventual goal of the international standards organization was to find ways to define everything in terms of frequency/time since we can measure time so accurately/precisely.
Actually, hard drive manufacturers have been using base 10 for quite some time now and not being entirely vocal about that fact. It works out to their advantage, after all. :-)
I see young Zyphod plays it safe.
I would assume that the pound needs some sort of accurate reference too so what is it? Or is it just defined in terms of what fraction of a kilogram the pound is?
Watersports, pfft. Dirty sanchez is where its at. Uknown German: Essen mein scheisse Cartman's Mom: Alrighty then
It's "Dakota."
The Spoon
Updated 6/28/2011
Just as the metric system struggles to have a reproducable definition of a kilogram, the imperial world will also be struggling to do the same with a pound/ounce. (if it isn't, it should be)
This means when the problem is solved for one, it is solved for the other as they relate with a simple ratio.
2.2 pounds to the kilo approx.
In order to appreciate the problem, try to imagine defining a kilogram in space. (Remember one should be able to reproduce these standard measures anywhere.) To get a metre just shine an argon laser and count the wavelengths. When you reach a certain number you have a metre. To get a second, count the vibrations of a casium atom. when you reach a certain number you have a second.
So what to do for a kilogram (or pound). Count a certain number of a given atom? Maybe. At the moment no-one's really got an answer. Comparing it to a known mass is the approach we're trying to get away from: put your test-mass and the reference mass on some sort of mega-accurate scale. They are the same - but how acurate is your reference mass? Compare it to the reference mass at the nations standards institute. But how accurate is that mass? you'll have to compare it to THE reference mass in France; and THAT reference mass appears to be losing mass.
The scientific community is trying to find an alternative route. Nothing obvious has surfaced as yet.
My car gets twenty rods to the hogshead, and thats the way I likes it!
The metric system is the tool of the
devil! My car gets forty rods to the hogshead and that's the way I likes it!
A choice of masters is not freedom
So I now weigh 75kg...give or take a bit :o
Wait till I tell my fiance that her weight
fluctuates on a weekly basis!
These pseudoscience concepts are getting out of hand.
I don't think we need "feel-good" physics.
Now they want to base a standard on a crystal ball?
You've just answered your own question there, and somebody also referred to these problems in a previous thread above.
If there want to do it this way wouldn't it make sense to use something inherently spherical like a Buckeyball?
Firstly, I'm not sure why the crystal must be spherically-shaped (unless it has to do with some kind of spherical-like Fermi-surface in k-space).
Secondly, buckyballs are difficult to isolate, specifically isolating just the C-60 variety.
Thirdly, and off-topic, they are NOT inherently spherical. They approach spherical but have distinct non-spherical features. If you diagonalize the Hamiltonian of C-60 molecules, at large wavelengths the energy eigenstates look like the spherical harmonics (as expected, you miss the small features). At higher energies, you can start to see non-spherical structures, though.
make world, not war
Move over Jared, the kilogram is the new Subway spokeperson...er...spokesobject.
Moderators for this website are stupid sacks of shit.
The stolen material is really called shitmamafuckinanium.
Instead of a semi-pragmatic approach, that requires routine real-world rejustification, why not simply train to a virtual concept that lies in an agreed standard, thus freeing everyone from having to point to something that is evident only by subjective change.
Slow news day.
Memorial day.
But the portable black hole thing flies ok w/you, eh? Ok, I won't tell....I promise.
http://www.spaceref.com/news/viewpr.html?pid=8991
Rawr rawr google link rawr.
Rawr.
'nuff said.
Obviously an evil conspiracy to undermine... er, the kilogram. Or something.
Do you know how hard it is to get your hands on even a little piece of Unobtainium?
I had a small Unobtainium crystal one time, back in the 60's. I got it from the drummer for the Airplane....he picked it up in China. I had one guy offer me two Vespas (one had a sidecar) and an unopened Guinness Stout for it, and I turned it down (the Guinness was cold, for Christ's sake). I kept that crystal until the divorce. She got it and the Sony TV.
Man, I miss that Sony.
I've been waiting a while to tell my high school chemistry teacher that a Kilo is 1024 of anything, and I do deserve that A. ~JM
Planck units, based on Planck's constant, the speed of light, and Newton's gravitational constant.
The Planck length is about 10^-34 meters, the Planck time is about 10^-43 seconds, and the Planck mass is about 20 micrograms.
I always understood that a gram was one cubic centimetre of water at 4C as that is when water is at its heaviest,.. Surely the measurement for a centimetre has not been shrinking??
Why not just use definitions that can already be made, such as 1/12.0107(8)-th the mass of one Avogadro's constant of a sample of 100% pure carbon-12? or 1/132.90545(2)-th the mass of one Avogadro's constant of a sample of 100% pure cesium-133 (which is its only naturally occurring isotope)? Or base it from the half the energy of the gamma ray generated by the annihilation of a positron-electron pair having no energy from acceleration, or something similar? Yes, it is a bit problematic that most of the physical features it could be based on now seem difficult to measure in a lab, because they relate back to something on the atomic scale, and the counting of objects at that scale or in such a number to be useful daily is difficult. At least, though, it would then be reproducible.
Having read the NIST article referenced by another respondent earlier, I can agree with their reasons for considering the adoption of another, more accessible standard. One of the cornerstones of science is the ability to reproduce results. Perhaps it is overdue that the unit of mass (kilogram) join its other basic breathern, the units of time (second) and length (meter), in being based not upon one physical sample, but upon a physical quantity that is reproducible and available to laboratories world-wide.
Reference for constants: The NIST Reference on Constants, Units, and Uncertainty
Is that what mass is in imperial units?
Or is it pounds per furlong?
No body, duh
Take the weight of whatever base item they're are using, and multiply it by a thousand.
That IS the point. There is not currently a base item to get the measurement of the kilogram or gram. The current measurements are based on relationship of mass to the SI standard Kilo bar, which is degrading and which is impossible to reproduce in every lab that needs to weigh things, so everyone goes off of an object that is weighed in relationship to device which was compared to the official kilo bar, in the US this would mean a NIST tracable weight. This is an error prone process and is only as exact as the comparison to the standard. By basing the kilo off of a natural and reoccouring phenomenom it can be reproduced like the rest of the SI units.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
Uhh, no!!! Just because you can translate weight into mass by taking into account the forces acting on an object, doesn't make mass and weight conceptually equivalent at all!
I thought 1 kilogram equaled the mass of 1 Liter of distilled water. Also 1 Liter of water was what filled a 1 cubic decimeter container. If that's true, why can't we just use these as the standard. Another thing to note is that gravity isn't constant as you move about the globe. If you are on high terrain over high density rocks, then you weigh more. If you are over the ocean where the crust is thin, you wiegh less.
Journal
Can you make your old games play at a good speed in XP and not make the sound choppy? Let me know if you can.
http://pcblues.com - Digits and Wood
Yea, the Frenchies build the metric (SI) system. Sooo much better than this inch-pound-mile crap...
I'd think the way to be most accurate (albeit rather unwieldy) is to quantify it as the mass equivalent to XXX units of energy, no?
"Faith: Belief without evidence in what is told by one who speaks without knowledge, of things without parallel." - A.B.
I agree, it's lame that the US does not use metric, or at least the non-scientific community. Having a science background, I'm perfectly comfortable with both English and metric.
:)
But we do have one thing right, at least. We measure the fuel efficiency of cars by miles/gallon (or kilometers/liter, if you like). I couldn't believe it when I first discovered that some countries use liters/100 km as a measure of efficiency. Talk about a bass-ackwards way of describing a car's efficiency. It's completely counterintuitive. Bigger should always be better, not smaller. What's the point of having a wonderful measurement system like the metric system if you can't even apply it usefully?!
"'It's certainly not helpful to have a standard that keeps changing,' says Peter Becker, a scientist at the Federal Standards Laboratory..."
Wow, someone should tell the computer industry that.
"Some of the metal plugs were issued to countries that later vanished, including Serbia and the Dutch East Indies. The Japanese had to surrender theirs after World War II. Germany has acquired several weights, including the one issued to Bavaria in 1889 and the one that belonged to East Germany."
SURRENDER YOUR KILOGRAM!
And, just as middle-aged people born on February 29th will tell you that they've only had 8 or 9 birthdays, things weighed just prior to the addition of the periodic "Leap Milligram" will appear to have lost mass overnight.
Think of the all pints that will be lost in bets near University towns!
"...all the labours of the ages, all the devotion, all the inspiration, all the noonday brightness..." yada yada
I always thought the standard was to use base 10 if you're selling it, and base 2 if you're buying it.
Favorite way to measure a Kilogram.
However, maybe I'm implicitly assuming that we have settled exactly what Avogadro's number is. But if we haven't, if we are still holding out for more and more accurate measurements of Avogadro's number, then yeah, we need to really nail down what a kilogram is. But that seems weird to me, because Avogadro's number has no units. It's just a count of atoms, playing the same grammatical role as the word "dozen".
Not true, there is such a thing as unobtanium, I saw it in a movie a coupla months back. Sadly, it was lost when it fell through a hole in the plot...
"Faith: Belief without evidence in what is told by one who speaks without knowledge, of things without parallel." - A.B.
I was about to ask the same thing, but you beat me to it.
Avogadro's number is a defined constant, so far as I can tell.
And since a molecule of C-12 is defined to be 12 amu, and since 1 mole of x-amu molecules masses x grams... isn't this already settled?
--grendel drago
Laws do not persuade just because they threaten. --Seneca
One of the responsibilities of the cleaning staff is to give it a good buffing with Brasso and a rag every night.
Nope - no chance of fingerprints or dust on that baby. Must be another explanation.
Cheers,
Jim
-- My Weblog.
You do know why Englishmen drink warm beer, right?
They all own Lucas refrigerators....
That this little quibble should affect the US, is just annoying. It's not like we're not capable of keeping and maintaing our own metric system.
The day we allowed ourselves to be this dependant on a rouge nation, was a dark day for sure. We are in all respects the greatest nation on earth, this is just a minor speed bump.
How small a thought it takes to fill a whole life
OK, the second is defined as some large number of the cycles of a cesium atom. I believe the meter is defined in terms of the speed of light.
Why not have the kilogram be defined as [Some Large Number] * (the equivalent rest mass of the energy defined by a beam of light with frequency Y)?
Fascism starts when the efficiency of the government becomes more important than the rights of the people.
which is heavier, a kilogram of lead or a kilogram of feathers!!!1111oneoneone
When anger rises, think of the consequences.
Confucius (551 BC - 479 BC)
I mean, why, instead of getting things horribly complicated, dont they *find out* why this thing looses mass? A possible reason could be that the material contains traces of substances that are radioactive, thus loosing mass by emitting radiation and particles. And, we could simply replace the reference kilo by a piece that does not contain any unwanted impurities and does not loose mass (the article seems to indicate that other reference objects do not loose mass). Hell we could just use one of those other reference kilos as the new reference. So what is the problem with that?
kg is actually a unit of mass. At sea level, you weigh 735.75 newtons. Your mass is invariant, while your weight is calculated as the acceleration vector * your mass (on the moon, you're 122.625 newtows, for example).
;)
The units of mass in imperial are called slugs, which is why no one uses them
--
Internet Explorer (n): Another bug -- that is, a feature that can't be turned off -- in Windows.
a reference mass must in some way enable you to *practically* compare some unknown mass with what you get from the reference. That is the reason why the caesium atom is used to define a second: you can build a device that will, based on that atom, tick away a very precise second. I doubt you can build a device that will allow you to weigh something based on a single C12 atom.
A kilogram is how much vaseline your average Slashdot reader buys per year.
you know, women turns 30 and suddenly she's 30 for the next 10 years?
:)
:)
She gets to 65kg and she remains there even though she puts on another 10kg
gotta love 'em
-- james
"The metric system is the tool of the devil! My car gets forty rods to the hogshead and that's the way I likes it."
It's not so bad, I mean you kill a gram here, kill a gram there...
Introducing the new Occam Fusion! Now with sqrt(-1) fewer blades!
...to hear that their own imperial units are also based on the SI. The inch, for instance, is defined to be exactly 2.54 centimeters, and the pound is defined to be exactly 453.59237 gram. So, when the kilogram dimishes in mass, so does the American pound!
A kilogram is the measurement of a certain amount of matter, not it's weight. Sure the two are related, but not the same.
A kilogram is the same on the surface of the earth, in outer space, or one the moon. Weight however, varies with gravitational pull or acdeleration.
In other words, weight is basically the mass of on object multiplied by whatever gravitational field you happen to be in.
Seriously now, where in the fuck are all these bad moderations coming from? I mean informative... Christ on a crutch, man. Is informative right next to funny on the list or something?
/., namely the Troll with "Excellent" karma? I know they're out there: real trolls who delight in the spoiling of anything worthwhile, yet who have played nice and gotten excelent karma. Naturally, these dudes get to moderate sometimes.
Could it be that this a new plague decending on
When they do get mod points they fuck it up on purpose, for example moderating funny and obviously fictional posts informative. Or moderating things flamebait, so other mods who simply mod posts the same as other people also mod them flamebait or overrated.
It's almost enough to make me wonder if there aren't organized clans of these foul creatures about with the same old troll goal, to get us, the more or less rational and intelligent to respond with a, "Informative, WTF?" post. I think it's the lack of consequences. These little mofos get a kick out of making grown-ups angry, but they know that if they did that shit in RL they'd get their asses beat or worse. They just love that the only thing we can do is rant and rave and we being who we are can't always resist the temptation to post "WTF?"
Thinking about it though, maybe that's the reason the slash-dudes are begging us to meta mod? They know this is happening, but they can't weed out the people from the mod pool unless they get lots of unfairs in m2. I know I won't be giving obviously wrong moderations the benefit of the doubt that they were accidents anymore.
Okay, editors. You can mod me down now as offtopic now, I guess I'm done ranting. Just for God's sake don't mod this funny or informative.
Freezing water was a bad idea, since the volume of water changes as it freezes, and I'm sure I read that they switched to 20C. The litre is, of course, a cubic decimetre or 1/1000 of a cubic metre, and is thus derived from the standard metre.
Whatever the reasons (practical?), the two standards were separated, but it's still quite easy to get a ballpark figure for the weights of fluids. Ten litres (2.624 gallons) of water weighs about ten kilograms (22.05 pounds). Some fluids will be less (gasoline), some more (beer, oils, mercury). There are other such shortcuts, too, so I ain't goin' back.
PS: If you Yanks are wondering why it's easier to get drunk in the UK, it's because a UK pint is 20% larger than a US pint. Standards are great - that's why we have so many of them...
(this is not a
Like an 11.5oz - 1lb can of coffee..
Take an OLD coffee can, like one from 10 years ago that reads 16oz on it and place it side by side to a new coffee can that reads 11.5oz. Stack the two cans to prove to yourself that they are the same physical size. Did the price go down now that you get LESS?? F*CK NO!! It went UP!!
Those 16oz cans were 89 cents a pound 10 years ago, and the now 11.5oz cans are $3.00 !!
And how about those new "Compact" 1 gallon jugs of bleach that now hold 2.5quarts??? Price go down?? No.
This is just a conspiracy to screw us even more now, now they can hold this up and say
"SEE!!! We have scientific proof that quanities are getting smaller!!" Always trying to screw the little people...
I'm pissed..
+1 informative
I propose a new standard of weight, called the Freedom-ogram, which is the weight of a French president's head on a silver platter. Which would of course be stored in New York. That'd show those cheese-eating surrender monkeys!
Gee, seems that nobody has anything particularly important to say about the topic of the post...virtually all the comments are off-topic.
I believe the difficulty of defining the kilogram is twofold. We traditionally measure mass as weight, the attraction of mass by gravity (usually the Earth's gravity). But it is difficult to measure either quantity precisely.
Mass is usually defined as the number of atoms of a given atomic weight, a difficult thing to measure accurately given the total number of atoms in a gram of any element. And due to the weakness of the gravitational force and its attraction over considerable distances it is one of the forces that has been difficult to measure as accurately as other forces, leaving the Gravitational Constant (G) as one of the physical constants defined to a relatively lower degree of accuracy than most other universal constants. The difficulty of measuring both these quantities accurately at the same time combine to make it difficult to define a precise standard mass.
The kilo shall be defined to be 1/80 of my weight. In return for the honor I promis to make the worlds people slim down.
Trolling is a art!
How can counting the number of silicon atoms in a perfectly spherical crystal of silicon be exact?
That's an easy one: grab an atom of the silicon sphere, mark a line on a sheet. Put the atom away. Repeat until you have no atom left. Then, you just have to count the lines you marked.
main(char O){O++&&(((O-291)*O+27788)*O-868020?1:putchar(O++
I thought a Kilo was measured from water - 1 ml (1cm3) of water ways 1 gram, ergo 1000ml (1000cm3) of water ways 1Kg. Additionally, 1 joule of energy can raise the heat of 1ml of water by 1 Celsius.
Or was my science teacher a blatant fibber?
sarcasm
(Assuming, of course, that you were replying to my response)
More than mere navel gazing.
If so, I bet it's related to that ol' big-bang theory, and the sky-is-falling theory. We might even be able to time travel by the time we get this "standard" measurement measured. Of course this whole concept has my head reeling (and possibly getting lighter). As a genX'r, I would think that by the 21st century we (the royal we) could've solved this so-called problem by now. The Y2K bug is something that can be realized, since it was due to the exponential advancement of technology. However, this is silly and ludicrous! And why can't kilograms be defined by moles (the molecule-counting type)?
ASCII silly question, get a silly ANSI.
Just to confuse the matter more, in the 1970s, it was common to use metric sizes of threaded copper pipe, which had external diameters in sizes approximating common fractions of inches: 13mm = 1/2", 16mm = 5/8" and 19mm = 3/4" just to mention some of them. These appearently were all threaded with 1mm pitch threads.
Later, these were replaced by true metric pipe sizes with compression fittings or capillary solder fittings. Now the sizes changed again, common ones are 8, 10, 12, 15, 18, 22, and 28 mm. And of course, one needed compression fittings made for 16mm and 19mm also, so as to fit the older pipes...
That's Europe. What I have seen in the US are the commonly found so-called 1/2" copper pipes with solder fittings, this is about 16mm (5/8") in diameter, so I guess they are still using internal diameter measurements. Similarly, the so-called 3/4" pipes appear to have about 21mm outside diameter.
I guess the easiest way to turn these into metric sizes would be to redefine them as 16mm and 21mm and leave it at that. At least the traditional inch-units pipe thread sizes are roughly the same everywhere!
SIGBUS @ NO-07.308
IF not, next time i go to US ... if i'll drive 130 ! If i get caught by a cop, then i explained him that US should be in SI so i drove 130 ... MPH instead of km/h :o)
;-) :o)
Will US be the last country to use the old English system for the international metric system ?
Are you so british-adicts ?, or did you forgot about tea's parties
C'mon, event the english people now order their pint in litters
I'm assuming the photons resulting from this transition would have a single and known wavelength, so you could say the mass equivalent to N photons resulting from this transition is a kg. IANAP, but this seems possible to me. It would also define mass in terms of time, which is apparently desirable. Then again, people much smarter than me have thought about this...
"The deluded are always filled with absolutes. The rest of us have to live with ambiguity." - Aristoi, Walter Jon Willia
Partnering with the NY Times and providing us with the article, sans registration:
h tml?ex=1054612800&en=a5e16828b6cf309b&ei=5062&part ner=GOOGLE
http://www.nytimes.com/2003/05/27/science/27KILO.
he kilogram is shedding at an appreciable rate
you mean I'm actually losing weight without doing diets or a workout !!
We know the charge of an electron, we can count electrons individually, we can measure distances to ridiculous precisions with interferometry...
Just define the Kilo from the volt.
The same as the kelvin system to the celcius for the temparature.
:)
The only things changing the remove of a constant (here the 0 is not the ice freezing but the absolute temperature).
C = K - 273
So here it is about 291K, sounds hot isn't it
By the way did anybody knows what is the 0 related to in the Farenheit degrees (F)?
And the metre is defined properly these days (as is the second) in terms of wavelengths of radiation.
Americans have never missed anything by not using the metric.
Turns out that the meter is screwed. Ha, told ya!!
Disclaimer: I am Canadian, and use metric.
> and why should I care if it detoritates?
Presuming you're American, you would use feet, pounds, find metric too complicated, etc, etc - so probably wont care if it does.
Except that the definition of the American pounds is based on the kilogram, so it actually does affect Americans when the kilogram diminishes in mass, because that means the pound does too!
Well tummyhertz is a pretty painful amount too.
As you can see I don't care about my karma.
Even a difficult as this sounds to do the Russians might just be able to do it. They have produced some very pure materials of other types. They are very good at it. It usually doesn't cost them millions of dollars to do this type of stuff either.
As you can see I don't care about my karma.
one point twenty-one jigawatts?
:)
That's almost a bolt of lightning by degrading metric standards.
On a more serious note, does the declining metre have anything to do with the rising Canadian dollar? And they say that Canada doesn't matter. Humbug, I say.
Price, Quality, Time. Pick none. What, you thought you had a choice?
Actually it's the kilograms that weigh less. It now takes MORE kilograms to match your weight.
"...and why should I care if it detoritates?"
"The metric system is the tool of the devil! My car gets forty rods to the hogshead and that's the way I likes it."
Unobtanium (iirc a fictional element, the chemist's version of "foo")?
Basing the system on a readings from a crystal ball (odd)?
gravity changes the mass (false)?
is this real?
I mod down anyone who says "I will be modded down for this", regardless of the rest of their comment
or a joiner? or anyone else you *need* to fix your house or utilities?!
Haven't been there personally, no, but funny you should ask; just spent close to 1.5 hours reading up on Bhutan (and nearby Sikkim, Arunachal Pradesh)! :-)
My understanding of the situation is that there seems to be very little chance of the authorities there allowing independent travel in the region (by which I presume you mean a registered-travel-agent-less backpacking expedition). I guess that's kind of understandable; this is, after all, the last remaining Shangri La, you wouldn't want commercialisation and cultural pollution that comes with largescale tourism activities.
Oh well, so much for my plan to be a 21st century David Livingstone. :-|
More than mere navel gazing.
Even in NZ you can order a pint of beer at a pub with no problem - and we've been fully metric for decades.
:-)
(Although, by law, it has to be at least 598mL from memory
The yard used to be defined as the distance between Henry VIII's nose and outstretched fingertip. Of course, subsequent kings redefined the yard to match their own vital statistics, so there are many obsolete English yards!
When I am king, you will be first against the wall.
Since the speed of light is 299,792,458 meters per second (taken from here), I am roughly 5.67 light nanoseconds tall. Interesting in a useless fact kind of way...
"Empathise with stupidity, and you're halfway to thinking like an idiot." - Iain M. Banks
...they might teach you about fractions.
If one mole of C12 gives you 12g from which you can construct 1kg, what's wrong with counting/creating a structure composed of 1/1200 mole, say, and constructing 1kg from it, knowing that it weighs exactly 12/1200g?
Given that we know mass and energy are equivalent, why not define the kilogram in terms of its equivalent energy? i.e. 1kg = E_kg/(c^2).
The energy could then be translated into the frequency of a photon having that energy using the relation E=h*v (that's v as in "nu"). So 1kg = h_kg*v/(c^2)
That reduces defining the kilogram to a question of defining the second. And the second is defined as 9192631770 oscillations of between the two hyperfine levels of the ground state of Caesium 133.
In fact, because of the accuracy with which we can measure time, the second has become the defacto fundamental quantity. For example, the metre is defined in terms of the distance covered by light in 1/299 792 458 s. (such a pity they didn't just go for 1/300000000...this could have been done by keeping the metre the same but defining the second slightly differently, which hardly anyone would have noticed)
The author of this post asserts his moral rights.
Your E=mc^2 idea is neat but 'c' also relies on time, which means that the equation relies on time, and thus doesn't solve the 'it relies on timemeasurement' problem.
Never underestimate the relief of true separation of Religion and State.
What's always confused me is that our "base unit" for mass is a kilogram. One millionth of any base unit foo should be a microfoo, but a millionth of a kilogram is a milligram, not a microkilogram.
I'm dimly aware of the mks v. cgs history, and I can accept that the kilogram might be a more practical unit than the gram for deriving the Newton, Pascal, etc.
But why was it decided to have two base units (i.e. the gram, which is the base unit for prefixing, and the kilogram, which is the base unit for deriving compound units)? Wouldn't it have made more sense to come up with a new name for the kilogram, which could then be a true base unit?
>The Pt-Ir cylinder is kept in France, and measured annually
:-))
I knew there was more to "The French Connection" than they were telling us. First they pretend like they've got nothin' to do with helping Saddam build WMD, and then they're skimming extra drug money by changing the measurement.
Just another day in Paradise
Uh oh did someone say France? Next thing you know the americans are going to want to call it the 'freedomgram'.
----- sXe
Just define a kilogram from Volt. As I understand that volt is now defined by some "Josephson junction".
Problem solved.
Ahhh, the bliss of ignorence....
-- Make software not war
Once I have obtained the entire reference kilogram, I will change it to be whatever I want! People will be fad-dieting to lose the extra 20kg's they picked up last night! With my recent investments in Jenny Craig and Richard Simmons workout videos, I'll be "sweating to the oldies" all the way to the bank!
MWAHAHAHAHAHAHA!
I'm a leaf on the wind. Watch how I soar.
Stupid Americans can't even get some of those right, with that not-quite-a-gallon you seem to favour.
The previous should have read... ...is that torque is in foot pounds, *meter Newtons*, etc. and work is in pound feet, *Newton meters*, etc.
As I said it can get confusing! In SI units say it in Joules!
"Oh drat these computers, they're so naughty and so complex, I could pinch them." --Marvin the Martian
I don't like the pound. It's got too many other meanings. For instance, you'll never be sent to a "federal kilogram-me-in-the-ass prison," now, will you?
I was under the impression that a gram was the weight (or mass, whatever) of 1 cubic centimeter of water. Then, a kilogram would be 1000 of these. Water is fairly common, on this planet anyway.
What's with using 1000 of something as a standard? Why don't we then call what we now call a gram a micro-kilogram?
"Would it kill you to put down the toilet seat?" -- Maya Angelou
Why not use a centrifuge for the Watt balance? You'd think that if you can have the centrifuge spinning at a constant rate parallel to the earth you wouldn't need to calculate the local gravitational field.
One of the problems is that a liter of water doesn't weigh the same in different places. The isotopic composition of the hydrogen and oxygen varies by location. A liter of water isn't a uniform collection of 1H and 16O atoms. There are varying amounts of 2H and 18O.
Mea navis aericumbens anguillis abundat
They call soccer, football. They call football, American football.
Uh, could it have something to do with it being (partially) made of iridium?
-Peter
You've had DECADES!!!
People have been refering to large quantities of software in 'tons' for a long time - they could simply make that an official quantity and derive the other units from that. Being digital, it would be easy to reproduce and measure, and any problems with unauthorized copies would be prevented by the DMCA. I'll nominate a forward looking quantity of 10 DVD's FULL as 'one ton' of software, or 47Gb.
try { do() || do_not(); } catch (JediException err) { yoda(err); }
I am sure this is somehow funded by those weight losing programs to tell people how they have lost so much weight just by screwing up 'how much 1 kg/lb means'
Well, at least in northern New England, the highway signs show distances in both miles and kilometers, so as to not confuse the visiting Canadians... But they still don't let you give Canadian quarters at the toll booths; I hate it when I get one of these things as change...
20:05 27/5/2546
...
...
... and it's really not handy for do-it-youself applications.
TOPIC: ergonomics
STUPID STUPID STUPID. i'm not a bunch of atoms, just like that
i would propose a new definition of weight like this:
on world pooh-day everybody messures how much they sh*t and submits it, we then
summe it and divide thru number of entries this would be very good definition of weight, because with this
we could build better water-supply system, better sewage systems, better planes, etc.
"our sewage-system can handle 10^16 "perfectly spherical single crystal of silicon" per minute", aua!
see it's pro-human weight system. who gives a damn about silicion!
oh oops! how to we messure the amount of pooh
i hate MeV, MOL just so you know. i just can't imagine it
Purity isn't the problem, the voids in the lattice aren't neccessarily the result of contamination. Instead, they are voids, truly nothing, little pockets of vaccuum...however you want to visualize it :)
Basically, as the crystal structure of the silicon is forming, a bit of crystal forms around a part that, well, isn't crystal. Imagine freezing water in a vaccuum, the water will not form a perfect ice crystal...it will be very nearly perfect, but not perfect. There will be both miniscule amounts of chemical contamination (which is somewhat easier to deal with) and misformations in the chemical lattice. Water freezes at a relatively low temperature so these wouldn't even be as significant as in a silicon crystal were the temps involved are much higher.
"Weights & measures: Metric"
Even the apparent change of 50 micrograms in the kilogram -- less than the weight of a grain of salt -- is enough to distort careful scientific calculations. How often do they clean the measure? A few particles of dust, a dead skin cell or two....
psxndc
The emacs religion: to be saved, control excess.
Great. A kilogram is getting smaller? That means I'm getting fatter!!
Good thing the pound is nice and stable . . I couldn't stand for my quarter-pounders to get any smaller!!
anything i tell you will cloud your opinion.
Replying to myself --
There's one sign on I-19 that I find absolutely hilarious though. It says something along the lines of:
Ajo Rd - 1000 m
Irvington Rd - 3000 m
Valencia Rd - 5000 m
The theory - Either they
A) ran out of 'k'.
B) had a whole bunch of '0's to get rid of.
C) don't quite get the concept.
The
dang... even platinum is lazy in france. maybe it wouldnt lose much weight if it didnt spend smoke instead of eating.
badamp-ching!
Whoa, a few facts for you: Bhutan is the only officially Tibetan buddhist country left on the planet (Tibet looses on knock-out). Mainly Kagyu lineage, Karmapa (the lineage head, equivalent to Dalai Lama) actually has Bhutanese passport.
Phones and Internet work (well, reasonably) in Bhutan, according to my friends.
I'm in a Unix state of mind.
IIRC, the kilogram is the last basic unit of measure still expressed in terms of an artifact, as opposed to though an observable phenomenon + mathematics.
IM(H)O, we need to do away with this, because artifacts exist in only one place. They can be stolen, damaged, or suffer from flaws and natural processes like the one we're seeing right now.
Of course, the flip side of having everything in terms of observable phenomena creates the problem of measurement, and making tools sensitive enough to do that work. Philosophically, the problem goes circular here, for how do you make a set of calibration weights for a scale, if you have to measure things to the atom first...
But in practice, there is no problem, because the measurement technology exists, and we're talking about the "standard" or "reference" units here.
Imagine having to calibrate a scale on Mars, or Alpha Centauri. Getting that artifact to the "job site", to make sure the scale is true, would be a bit of a chore.
A kilogram should be expressed not in terms of the number of atoms in a particular crystal, but rather in terms of the mass of X moles of standard substance Y.
We can assume (if we can not, then all else is a lie) that a particular isotope of a particular element will have the same mass eveywhere in the Universe. We know the number of atoms in a mole. Problem solved.
The REAL jabber has the user id: 13196
What you do today will cost you a day of your life
A meter was the distance light traveled in 1/299,792,458 of a second. One second is the time that elapses during 9,192,631,770 (9.192631770 x 109) cycles of the radiation produced by the transition between two levels of the cesium 133 atom. Just thought you would want to know.
I/O, I/O, its off to disk I go, with a read and a write, and a bit and a byte, I/O, I/O, I/O, I/O
Or gather all the robots on the Galapagos Islands, and have them vent their exhausts straight up. This will push us into a wider orbit, lengthening the year by exactly one week, which will, by order of President Richard Nixon's Head, be a party every year.
-1, Groaner
I can't say that I don't give a fuck. I've just run out of fuck to give.
To detect a change in mass, they must be measuring it against something they regard as a more reliable definition of the unit of mass than the thing they are trying to measure, which is itself supposed to be the fundamental reference.
If they really believe in a reference kg., the conclusion should be that all the other masses in the world are increasing in mass. If not, then who cares about it?
For instance: I won't get a car that has big kilometer numbers and little mile numbers until the speed limit signs have the speed in kph listed in large type with the speed in mph small type at the bottom. I won't get a tape measure that measures in meters/cm until lumber is sold in convienient metric lengths. The building codes should all be in metric too if they are not already. When the gas and milk are sold in litres, I'll have a better intuition as to how much one liter is ( soda is sold in 1 and 2 litre increments so I kinda do already )
I must have both metric and inch type wrenches because it is completely random as to which type will fit, even on the same item. Who knows if the 50yd line will ever become the 50m line in football or if the game might subtly change by using the slightly longer meter. If they stopped selling TVs with 27 inch screens and used centimeters, people would learn to like centimeters.
The only way we're ever going to switch is if the government mandates that all the measurements of products are given in metric in larger type than their equivalent in ye olde inches/feet/furlong system, and that the government must use that system exclusively on all signs / documents etc.
Eat at Joe's.
In other words: it's surrendering !
Admit it - you post on Gwlad!
Changing to the metric system has nothing to do with the war. A lot of European countries were on it before WW2, and the British started the change long after postwar rebuilding.
Canada also started switching in the seventies, and the switch is pretty much complete, as you will know if you come and visit.
Or we could wait till the moon ( which is getting farther and farther away ) slows the earth's rotation to 1/360 of a year and then run/drive/pogo-stick eastwards to keep the day from lengthenting any longer to we don't end up with month long days where we get frozen and fried.
Since 24.35 hours a day makes hour math a lil hairy the hour and the second would have to be redefined too - preferably using base 10. Then you could have the morning hour the brunch hour, the lunch/siesta hour, the dinner hour and the tv hour, the sex hour and the night hours.
Eat at Joe's.
because they use kilometers on Star Trek!
Reading through the responses to this post brings back fond memories of Dr. Wade's DiffEQ class back in 1996. I recall a homework assignment that required solving a differential equation, then plug-n-chug to get the numerical answer. I was the only non-math major in the class and the only student who had the correct answer. The reason I had the correct answer was that I was a chemistry major familiar with systems of measurement, and the problem specifically stated to find the MASS of the object in the English system. Everyone thinks the measurement of mass in the English system is the POUND, which is completely incorrect, the POUND is a FORCE unit. The mass unit of measure in the English system is the SLUG.
That would be great if everyone could remember what twelve cubed was.
The S.I. system of units is no more scientific then the Emperical system. In S.I. you have the meter which is the length of some dead kings/queens arm; in emperical you have the inch which is the length of something else totally retarded (a yard is 36 inches).
Ounce vs. Kilogram is the same thing. Measurements that are totally arbitrary and meaningless.
Having a base of ten is fine for you S.I. people, but why haven't you changed the clocks in your countries yet to S.I. units? (If you research hard and long enough you'll find an S.I. clock). The reason is that the US will never change to S.I. And most of the world's economies are linked to the US.
If it is the standard, how to they weigh it?
Maybe the weighing apparatus changed...not the mass itself?
Anyone know how they determined the standard is getting "lighter" or less massive?
JoeK
What Would Sutekh Do?
If that's not a change, i don't know what is, folks. This was bottled and labelled in the US. It's one of many small changes- the Liters are being labelled above the pints and ounces.
At least in some cases.
"I'd say 'Have a good time,' but arson is still illegal.
Somebody is emblezzling... just really really slowly! "Hey buddy, turn out your pockets... hey... is that a platinum atom?"
The standard 1 kg block should be replaced by the 1 kg Christmas Fruit Cake. As everyone knows, it is indestructible, and only one exists in the entire world (people just keep mailing it around to each other every year).
---- ---- --- -- --- ------ Keep Cool But Do Not Freeze
"The agency guards the international reference kilogram and keeps it in a heavily guarded safe in a château outside Paris". DARN IT, they need to guard it better!! someone is obvioulsly stealing!!!! Call Inspector Clouseau, he'll take care of it.
If it's too difficult to precisely measure the number of atoms in a kilogram of something... why can't they calculate using a gram instead. Then just multiply the results by 1000.
Is there something that prevents this from being a useful method?
but they said diamonds are forever!
HA! All you wierd for-en-ers switching to your mit-rik system! Shows to go ya!
I have no tag line
Look at your circuit board, I bet the layout is based in mm and approximated to the closest english measure.
Consider all of the CNC tools (found in machine shops), to switch between english and metric is a matter of pressing a button.
Most auto mechanics have to buy english and metric tools.
I bet if your serveying equipment is high end there is an easy conversion to make it metric.
Just think about it, it truely is low hanging fruit. Why would any company limit their products just to the US, when they could provide them to the entire world without much effort?
1 Kb = 2^10 bytes (1024)
:)
1 Mb = 2^20 bytes (1048576)
1 Gb = 2^30 bytes (1073741824)
It was those damn lazy scientists! Now it's comin back to haunt us!
What standard isn't arbitrary? There's always another way to do things. The advantage of using the metric system is it's the same arbitrary measures that are used everywhere else.
I think the US will end up using the metric system whether they like it or not. With the proliferation of international trade we are being flooded with products that use the metric system. Eventually we'll give in.
In 1893, the metric system was adopted as the standards for length and mass in the United States.
Somehow, in the intervening years, nobody remembered to tell the general populace.
Then, in 1975, Congress passed the Metric Conversion Act. The U.S. Metric Board was established that same year, and the metric system was finally adopted.
Or not.
The U.S. Metric Board was dissolved in 1982, and we are now the only industrialized nation which does not use the metric system.
Are we a nation of mental defectives? Will it really take another 110 years before we finally go metric?
Neopets - the best free game on the Int
I was always under the impression that the metric system was based off naturally occurring phenomenon. I thought the meter was related to the wavelength of something and I thought the cubic centimeter was really important as one cubic centimeter of water weighed one gram and the amount of energy needed to boil that water was a joule or something like that.
With today's technology why not set the units of measurements to things like a cube of water and the length of a light wave? That to me seems like it would make the most sense.
Divisibility by 3 and 4 is a good point. How about basing your projects on 12 cm units then? Or alternately, 36 cm which is close to a foot (14").
Duh... simple people. They KNOW what the KG weighed at the start (2.2046.... pounds.) That amount is convertable to anything else (like X number of silicon atoms, etc.) I don't know why this is that big a deal. Must be the French...
Moving to the metric system... 25.4mm by 25.4mm.
You can use a pound as a unit of mass
Well, no. And anyway, the unit of mass in the imperial system is the 'slug'. Really.
Well, if a unit of constant mass is getting lighter, obviously the gravitational field is changing. Duh.
I am an american engineer who commonly deals with both the metric and english units. My opinion is that america hasn't changed over too quickly because of the massive infrastructure and interia built around the english system, *and* because conversion between them is quite easy. I think anyone who commonly encounters both systems has mastered the conversions necessary, and it really isn't a big deal to them. It's a trivial task to convert. Both systems have thier merits, and were well thought out for what they were used for.
This notion that measurement system compatability is a major issue with world trade and technology is just not true.
It's not a big deal folks, move along.
It's a pity to misquote such a beautiful saying.
Nicola Tesla actually said (as a reply to Edison's babble "genius is one percent inspiration, and ninety-nine percent perspiration"):
"If Mr. Edison would think a little more, he would sweat less"
Serban
Things to remember:
"Pipe" is described by it's nominal diameter and strength ("schedule"). Nominal diameter is neither internal nor external. ex: 4" schedule 40
"Tube" is defined by the external dimension (not necessarily diameter) and wall thinkness. ex: 4x4x1/4 (a square tube, 4" on a side, with a 1/4" thickness.)
Is it just my observation, or are there way too many stupid people in the world?
do the math
to illustrate, with a 10% difference:
Year 2003 KG = 1000 2003 grams
Year 2010 KG = 900 2003 grams
You currently weigh 80kg (176lbs)
if your mass doesn't change
in 2010 you will weigh 89kg
Doh...
At first this sounds silly, but it makes sense to use a standard to acutallly benchmark messures and since this one seems to have served quite long (iirc Napoleon was the first to establish the metric system in a broad range) it might as well be also used today.
The flawed weight could be due to magnetisim (scales base/table/platform/whatever and cylinder repelling each other) caused by microwave induction from cellphones or the likes. I wonder if the place where the standard is weighed is shielded form this. I would be supprised if not.
We suffer more in our imagination than in reality. - Seneca
Sure, America will move out of the dark ages when the U.K. and Japan start driving on the *right* side of the road! =D
When you look down, what you're seeing is how your feet looked 5.67 nanoseconds ago....
Just as a minor correction ... the volt is no longer defined in terms of the kg. The international definition of 1 Volt is now defined in terms of the "Josephson Effect" and is an effect observed in superconducting materials that are interupted by a normal metal.
It turns out, that even without an applied voltage, there is still a current in the system, and after a voltage is applied, the current oscillates at a very predicable rate. Thus, the volt is now defined as the potential required to give a specific number of current osciallations in a Josephson Junction.
Nit-pickey I know, but maybe of interest.
The watt balance solution seems to be linking the Kilogram (mass) with force (weight). This is not entirely desirable, since something that masses a kilo on earth will still mass a kilo in space, or on the moon, or on jupiter. It's mass doesn't change, only it's weight. The Watt balance then, would not only be impractical (imagine having to construct a "3-story structure" every time you want to accurately weight something?), but downright useless for many aerospace applications. Any system of measurement that's dependant on the phase of the moon for it's accuracy should immediately be discounted, in my opinion...
I am alone, yet I also surf the universal backwash of undifferentiated Being, which is LOVE.
12^3 is
1000 base 12
where 11 is a
and 12 is b
1000 base 12 = 1*12^3 + 0*12^2 + 0*12^1 + 0*12^0 base 10
= 12^3 base 10
You talk as if 1 kilo is some special number that everyone has a mystical understanding of because it looks so simple in our number system.
A Usenet Troll Triumphs on Slashdot
Range of natural variations (Atoms %) source
H1: 99.9816 - 99.9975
H2: 0.0184 - 0.0025
O16: 99.7384 - 99.7756
O17: 0.0399 - 0.0367
O18: 0.2217 - 0.1877
For example, fresh water is known to have lighter water molecules than sea water because fresh water comes from evaporation. So one problem is how to define "water" precise to one part in 100 million.
If a Spring-Loaded scale was being used at locations with different gravitational force, your point would be correct. But a balance will match the MASS of two objects under any gravitation force.
An object with a pound of weight in a fixed gravitational field has a fixed mass; thus, the description "weighs 50 pounds at Earth sea-level" is a description of the object's mass. And so "pounds at earth sea level" is a unit of mass, convertible to other units of mass (such as the kilogram) by a fixed constant.
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
The "official" kilo is too arbatrary for me. .1M
1 kilo = the mass of 1L H2O at 3*(i think)C
1L = a 10x10x10cm box
1cm =
1M is a fraction of a great circle.
So who needs the block?
What I wonder about is why they use a sphere and not a cube or a tetrahedron.
If they have a perfect crystal, then it might be possible to use etching to align the sides of the cube or tetrahedron(with silicon having four bonds ?) to the lattice of the crystal and then count the layers either directly (e.g with these raster tunnel microscopes) or by using interference effects that would group a fixed number of layers.
Is a silicon crystal pure enough so that the basic orientation of the crystal lattice is undisturbed over distances of 10cm ?
I think the number of atoms along the sides of a 1kg cube of silicon (app. 8cm) would be low enough ( 10^9) so you could hope you could actually count the atoms in reasonable time (eg. within 20minutes ~= 1000secs at 1MHz counting frequency)
Of course, a sphere would be easier to handle and less prone to chipping bits off.
Another idea about the silicon cube would be to apply "wear and smear detection circuitry" on the six sides using standard silicon semiconductor processing, e.g by covering the surface with a mesh of little custom cells that would detect the presence of their neighbors and report failed cells when they do not respond.
But I think this would introduce too much error,
as 50ug error on the old 1Kg iridium slab (1:2*10^7) would translate to a dimensional error of just about 1nm, less than 10 atomic layers - and these guys are aiming for a noticeable improvement on this !
No wonder I've been putting on weight!
According to the Prime Pages (http://www.utm.edu/research/primes/), the speed limit in Trenton, Tennessee is 31 miles per hour. A fondness for prime numbers? No - 31 miles per hour is very close to 50 kilometres per hour.
===
Conversion between mph and km/h is simple when you know the trick.
1 mile = 1.609344 km
Limit of ratio of successive terms in Fibonacci sequence ~= 1.618034
So for small numbers you can approximate by using the Fibonacci sequence: 5 miles is about 8 km, 8 miles is about 13 km, and so forth.
The only thing necessary for the triumph of evil is for good men to do nothing. - Edmund Burke
> I can't think of anything more ludicrous than basing a whole set of measures on the number of digits on a particular primate's hands.
...). As was noted, many people already use "tenths of a foot" for measurement for this very reason.
The metric system follows directly from our number system, which is base 10.
Our number system is base 10 because that's what medieval Florentine bankers used, because that's what earlier Arabic thinkers used, because that's what previous Hindu and Egyptian civilizations used. The roots of our base 10 number system go back 4000-5000 years (Babylonians and Mohenjo-Daro), so this is hardly something you can blame on the French Revolution (unlike, say, modern democracy...).
Accordingly, our number system ain't going to change from base 10 any time soon. Given that, we might as well make life easy for people and make measuring and counting the same thing (use base 10 for both) instead of making people learn separate systems for different types of measurement (12 inches, 16 ounces, 3 knots, 1000 varas square,
For heaveans sake it has a vapor pressure of something on the order of one atom per universe. It is durable and dense. I really like physically achievable in the garage standards and I don't think I can afford to measure the exact number of atoms in anything, nor afford a absolute pure silicon crystal sphere or the like.
- Tjp
I am in wallow with my inner money grubbing capitalistic pig. ... Oink!
Don't use Moe for a machinist. Besides the shipping from Springfield is enormously expensive.
- Tjp
I am in wallow with my inner money grubbing capitalistic pig. ... Oink!
Why is it deteriorating? Evaportation and a small amount of surface reaction.
Keeping it in a vacuum would not help either, since evaporation increases with lower pressure. At best you could keep it under some idealised pressure (minimising evaporation vs surface reaction) in an inert gas.
Presumably some time in the future kg will be defined as a certain curvature of space or something.
How can Canada move to a metric system when it is sitting next to the country's largest trading/travelling partner, who refuses to change? Maybe with the increasingly deteriorated relation between the two, we poor Canadians can finally break free from the wrath of the imperialists (that hasn't stopped Quebec's metric progress though).
Of course things shrink in France - that imbred excuse of a nation is probably shaving a little bit of the cylinder off every year just to f*ck with everybody. I guess they have nothing better to do (except support international terrorism, that is!).
I have bad karma for speaking my Republican opinion. USA Rules!
We have started. So much so that I need both metric and english tools to work on my American made car. One or the other would have been much nicer. I have a dashboard on my Mustang that reads in either metric or english (well, or french for some units). I have mixed electronics equipment as well. It is all rather a pain in the !$@#. At least at the individual item level, I'd like it to be one or the other. BTW, the beauty of the "standard" measures is that almost all important measures are one sylable and that applies when the scale uses needs to be changed. inch, foot, yard, rod, chain, mile, etc. ounce pound stone ton ... cup pint quart (gallon must be an outlier as are the other larger liquid measures which seem to be two sylables), volt amp watt ... Just as simple as the metric system, just a different axis if you have the right point of view. BTW sign me up for one of the obsolete Bridgeport turret lathes, milling machines, shapers, etc. in english measure. Especially any CNC ones. It is not all that tough to change the gearbox over and the dial plates to make it metric which if you are giving 'em away to go metric I'd be happy to do.
- Tjp
I am in wallow with my inner money grubbing capitalistic pig. ... Oink!
And the obvious answer is... we can't do either!
I think we can count handfuls of atoms, possibly even hundreds or thousands... But you're asking for trillions of trillions!
GPL Deconstructed
(Posted earlier of course, but just for the heck of it)
A $48m state-of-the art digital telephone network to rival those of Singapore and Hong Kong.
More than mere navel gazing.
Fill a liter with tap water and call it a kg if you want, but *scientists* need a definition precise to 1 part in 100,000,000 at least. Simply the fact that you'd have to distillate and select a specific isotope of hydrogen and oxygen to get any meaningful standard would make the standard quite far from the tap water definition average Joe would like. Once you accept that, other materials are more easy to deal with than water so that's why they preferred to make a standard out of something else.
It's French. Hence, most people in the US either don't care or want it renamed "liberty pound". The only people here I know who use metric on a regular basis are engineers, scientists, pharmacists, and drug dealers.
As long as there is a Second Amendment, there will always be a First Amendment.
The ambiguity is already there -- when you hear "Mega" in a computer context, you never know if it's referring to 1048576 of something (filesystem Megabyte, RAM Megabyte) or to 1000000 of something (bandwidth Megabit, hard drive Megabyte). So it can't really get any worse. At least with the modification you'll know for certain what someone means when they say a MiB.
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
...the UK, which measures its speed limits in miles per hour and its beer in pints?
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
As far as I'm concerned everything is inevitably fallible in its own nature. Much like basing your belief system off text written by another man, basing measurements on laws written by man is a sure fire way to take a giant bloody step over the 'key', whatever that may happen to be.
Funny how simple discussions with your neighbor can key you in on undeniable 'facts' that remain as such simply because a text book professor tells you so, or a laboratory tells you what can't really be defined, such as time. Time itself doesn't truly exist, as it was created as a means of measurement, which in comparison to other incomparably larger objects in same space, is pretty fucking limited. I won't deny that these laws have brought us to the point we are at, but they've limited us to an infinite degree.
I usually disagree with myself, but I won't allow words and definitions to guide my theories. The only reason I don't believe it is impossible to travel faster than the speed of light is because the math is based on a fallible scale. As I like to tell people 1+1 does not always equal two. Who's to say the entities being added aren't already of a single greater entity, or that their matter doesn't coexist in a frame of reference yet to be determined? Just because you can't mush them together like Play-doh doesn't eliminate the possibility they are one. Everyone has theories; Einstein just had some that worked, until Hawking fixed a few typos and filled in the text where the toner ran out...
So basing the world's evolution in theoretical physics and chemistry on fallible laws of our own made up and obviously insufficient scale is the crippling wound which refuses to heal. This whole kilogram business is nonsense; as the scale is inferior. The temperature scale is universal (despite calculation difference between them), as they all agree on an absolute zero. Until they determine mass at absolute zero, then there will be no unit of measurement that crosses every continent, planet, solar system, galaxy, etc. In my own theory, a black whole is opposite of science beliefs. It is zero mass, and the math won't agree because of all the previously mentioned.
Don't be a zealot.
on the sixth day God created man.
on the seventh day, man returned the favor.
I think that's because otherwise there would have to be some massive car-swap for drivers and a lot more speeding fines for people with the always lame excuse.
but really it was the kilogram that was losing it. :-D
in my life God comes first.... but Linux is pretty high after that
Francis Smit
The rest of the world is using it, your units are defined in function of it, but you still have the face to claim that people advocating the metric system (only to you, stubborn USians in order to facilitate commerece, etc) don't have enough pull.
That US parallel universe in which many USians live is absolutely detached from reality.
IANAL but write like a drunk one.
.... is not what you use to iron your shirts.
Oh yes, and I believe Buthan is a fundamentalist Budhist country, like if that made thinks better.
IANAL but write like a drunk one.
Not *any*
If the gravity field is null, you're out of luck with that balance.
Likewise, if you're gravity field isn't "constant enough" (spatialy), the comparison won't work either