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New Book Says The Meter Is all Wrong
Bill Klemm writes "Ken Alder's new book 'The Measure of All Things' scandalizes the metric system as 'arbitrary.' CNN has a little article about a new book that explores the 'odyssey' of Delambre and Mechain to find the perfect unit of measure."
0 degrees - the energy at which a hydrogen atom is at rest. 1 degree would be the energy at which hydrogen is one quantum state higher than rest.
1 length - the distance across 1 hydrogen atom
1 time unit - the time required for a hydrogen nucleus to vibrate once
Then you can apply whatever kind of metric multiples you like to these and voila, you are done.
Who cares about the actual size of the Meter. Of course it's arbitrary. All units of measurement are arbitrary....
All I want is a system that allows easy conversion to other units. None of this 2 cups to a quart; 4 quarts to a gallon, a dozen gallons to a bushel and a peck....
Originally, you see, the metric unit of distance was supposed to be one ten-millionth of the span from the north pole to the equator.
But the Earth isn't a perfect sphere -- it's an oblate spheroid, flattened at the poles -- So, does this mean that the perfect measurment for the world is the cup/chest circumference sizing standard we've been using on bras for years?
Dang, the earth is hot.
--"The perfect example of the man of action is the suicide." - William Carlos Williams
Mass: 1 atom of hydrogen What else would be required in this system?
why choose water as the determining factor in deciding what a gram is (g=1cm^3 of water) --> because it's the most important element to us that is easily available and pourable into cm^3 boxes. and the fact that the earth is elliptical and not circular isn't important; it's that it appears circular to us (no it doesn't appear flat unless you've never seen pictures from space). anyway, that doesn't matter b/c we define the meter according the speed of light, which is just a/b as unarbitrary as you can get. a system of measure is for use by people. thus it should bear some relation to people, and that will make it arbitrary. the most important factor is uniformity, which the meter system has in abundance.
...And when that future failed to arrive I began to wonder why.
Because people had been using the imperial system for so long, it became (and still is) a major undertaking to convert. You don't just say "Okay everyone, we're going to use Metric for everything now!"..
There are books of formulas, constants, tables and charts that need to be rewritten. There are machines that need to be rebuilt and redesigned. There are entire conventions that need to be done away with and started afresh. This is extreamely difficult, costly and possibly dangerous to just 'do'.
Only in the more modern technologies has the metric system really taken hold, and everything else has been undergoing a gradual conversion.
The metric system has many advantages over the imperial system... like having destinct units for mass and force: grams and newtons as opposed to just 'pounds' (pound-mass, which must be converted to slugs for calculations, and pound-force). As well as not having any unweildy fractions. Non of that 15/32 of an inch.
However, that does not make the imperial system any less useful. If you really think about it, any measurement system is going to be arbitrary, and it will be valid as long as it's consistent.
=Smidge=
The US dosn't use or approve of the metric system, so why does it need to change the spelling?
what we need to do next is do away with the hour, minute, etc. As in Vernor Vinge's A Deepness in the Sky.
I know lots of things. Most of them are wrong.
SI base units:
:-)
Length - already covered by the AC
Mass - already covered by parent
Time - AC
Angle - there are very good mathematical reasons for using radians
Solid angle, luminous intensity - does anyone ever use these ones?
Amount of substance (mole in SI) - I'd hesitate to call this a dimensional unit, since it's just a very large number.
Temperature - the AC quoted a unit of energy. Temperature is not energy, so you'll need a real unit of temperature.
The other missing one is either current or charge (intuitively, you'd think the charge on the electron would be the ideal base unit, but in fact SI defines that in terms of current (charge/time), because current is easier to measure, using the force between current-carrying wires).
thanks to cofc.edu via Google
A quote:
"I remember my fifth-grade teacher instructing us in the metric system and telling us we would need to learn this material because we would all be using it in the future," he says. "I believed her, of course. And when that future failed to arrive I began to wonder why.
He should get a clue, the rest of the world uses the metric system, this future has materialized. If one country wants to be stubborn and hold out, whatever.
Anyhow, the real beauty of the metric system is that it's various units of measurements make sense. As in, a centimeter is a hundredth of a meter, a millimeter is a thousands of a meter, etc. The imperial system wouldn't be so strange if it was 10 inches to a foot, but it's not.
Anyhow, the meter is not the only part of the metric system, it also encompasses temperature, weight, etc. And the meter is certainly less arbitrary than the foot!
You'ld think at least NASA would get this.
"A language that doesn't affect the way you think about programming, is not worth knowing" - Alan Perlis
24 hours is a day discovered to be arbitrary. 100 pennies in a dollar discovered to be arbitrary. 4 quarts in a gallon discovered to be arbitrary. 67 trolls in a Slashdot article discovered to be arbitrary...
We have the hogshead, the dram, the cubit, the bushel, the gross, the furlong, and even the jigger. There's nothin' wrong with 'em by crackie!
How ya like dat?
We all knew this would be posted ;)
Comment forecast: Bits of genius surrounded by a sea of mediocrity.
In meters, for example, mathmeticians had to use a definition that allowed others acrossed the world to also come up with an exact length. If these mathemeticians truly wanted a non-arbitrary system back then, they could have made a "master meter stick", whose length was not based on anything arbitrary. But such a system would never work, because then they would have had to ship copies of the master meter stick across the world. The ratio system was much more practical.
Mass and volume are arbitarary in 2 ways. They rely off our arbitary meter, as well as the arbitary earth's gravity. A definition I've heard is that 1 cubic centimeter of water at sea level weights 1 gram and has a volume of 1 mL. Try taking a cubic centimeter of water to a different world, and you'll get different measurements. Today, the official definition of a kilogram is the mass of an international prototype in the form of a platinum-iridium cylinder kept at Sevres in France. (By the way, you could also say that using water is also arbitrary, since we earthlings used a commonly found liquid. The sea level is also arbitrary, since it varies across different coasts, as well over time)
Temperature is also based off the arbitary earth's atmosphere. 0 degrees Celsius is the freezing point of water at 1 atm (the standard air pressure of earth). If you increase or decrease the pressure, you'll get different freezing points.
Anyways, my point is, that it was next to impossible to come up with a practical system without it being arbitrary in some way or another.
P.S. If anything in this article needs correction, please correct it. I'm probably wrong somewhere since everything I said was what I remember from years ago.
The CNN article appears to have been written to give the impression that Alder is anti-metric. It's necessary to read into paragraph 23 out of 26 to find out that Alder is actually pro-metric. Before that, the article quotes Alder so it looks like he's anti-metric.
mods metamodded as "Unfair"
1 cubic centimeter of water = 1 millileter of water = 1 gram.
Even though they are all arbitrary, who cares? There is no such thing as a non-arbitrary unit of measure.
Let's say you set the unit of length equal to the diameter of 1 proton and the unit of mass to the mass of one proton. It's still arbitrary! You could have picked the radius, or the neutron, or the electron. Or a hydrogen atom. No matter what you base it on the process of picking something to base your unit of measure on is itself arbitrary. The metric system is easy, base 10, the way we think. It works.
As they say, anything less would be uncivilized.
The GeekNights podcast is going strong. Listen!
Man, I wish I could spend all day coming up with inane assertions and then writing books about it and getting paid for it.
Of course the meter is arbitrary! Until you get down to the quantum level EVERYTHING is arbitrary. That's the way the universe works!
Geez!
You are in a maze of twisty little passages, all alike.
Even if you somehow find something non-arbitrary, and use that, you still arbitrarily decided to use something non-arbitrary. Just because you decided to use the size of the universe before the big bang as your basic unit of measure doesnt mean that England did. Everything is arbitrary.
-- 'The' Lord and Master Bitman On High, Master Of All
I remeber the furore over the conversion to the metric system well. I was working and the lowest crappiest most poorly managed lame-arse crumbling sorry fucking excuse for a cheapo shit-hole supermarket at the time.
I prefer the metric system, it makes sense, in ways already mentioned here. What I do not agree with, is our Government forcing shops to sell stuff in metric units, and fining retailers for selling stuff in imperial units...
What the fuck? Nobody is getting ripped off, the supply chain all the way to the shop shelf is metric, but the customers are forced to buy stuff measured in metric units; does it matter? NO! My rant is about the government fining and jailing private traders who sell in imperial measures. They are just pleasing customers! And metric units are always there to be used if desired.
When I worked at a timber yard, long after the metrication debacle, most customers still used imperial measures. They were brought up on them, simple as that. Thus, 8foot X 4foot shhets became 1220x2440mm sheets, and 10feet became 3050mm. Great for mental arithmetic exercise.
They could have educated people about both systems, and let people choose. Within a few decades the imperial system could be done away with quite easily. But no, it has to be shoved down our throaghts in almost no time at all!
I'm only 20 and I remember the metric system being taught at school: Cubits, digits, palms, etc...
Ali
Ph33r m3!!!
When in school, all of the teachers were teaching metrics, execpt for the shop teacher. And I liked his reasoning.
For everyday tasks, a meter is too big of a measurment, and a centimeter is far too small.
In addition, it's easy to accurately measure sixteenths of an inch, while it is near impossible to even measure quarters of a centimeter. Go look on a ruler if you don't believe me.
Sure, the math works out great, but in the real world, 6 feet is much easier to comprehend than 2.4 meters (or whatever the correct conversion is)
-- If you try to fail and succeed, which have you done? - Uli's moose
Trust the French to get the unit magnitude wrong. However they did manage to copy the idea of decimal scaling from Thomas Jefferson, presumably on one of his visits to France (which he rightly felt was inferior to Virginia).
"Jefferson continued, "where he had only tens to carry forward, it was easy and free from error." Jefferson began advocating decimal reckoning as an orderly alternative to the currency chaos in 1776. In 1784, after his "Notes on the establishment of a Money Unit," he recommended a system with the advantages of convenience, simplicity, and familiarity. The Spanish dollar was convenient in size, its decimal division would make computation simple, and its multiples and subdivisions would accord with already well-known coins. "Even mathematical heads," he admitted, "feel the relief of an easier substituted for a more difficult process." Jefferson's lucid arguments overwhelmed rival plans and the United States soon became the first nation in history to adopt a decimal coinage system."
Why do so many people get this wrong?
It is not illegal to sell goods in imperial measures. All goods sold by weight, volume or size must be priced in metric (with the exception of draught beer and cider, and milk if it is in a returnable container), but they may also be priced in imperial if the retailer wants to.
Blaming difficult divisions on a system of measurement is stupid. The reason the metric system is so easy is that it mixes with the base we use and we all use base 10.
All of those people arguing that metric is bad due to this difficult division need to realise the problem is base 10.
I will now announce my plan to improve the world. We move to base 12. "How to get there?" you ask. We convert 2 letters to numbers, but which 2.
I propose Q & X. X will be replaced by ECKS and Z where it is necessary. Q by KW, in Iraq is will be replaced by c, ck or maybe rc (Rhymes with arc). This will have several benefits, SEX ==> secks and is thus longer for everyone who speaks English. Keyboards also become smaller. 3 rows of 8, with the numerals stuffed somewhere (not sure about how to solve that).
On the numerical side we can now convince aliens we don't count on our fingers. It will also help to weed out the ignorant (who DO count on their fingers).
There are various benefits in terms of division.
All numbers are now reported in base 12, the numerals are as follows: 0 1 2 3 4 5 6 7 8 9 Q X
The best one is time: there are now 50 seconds in a minute, so we can move 2 minutes to one, then we get 26 minutes in an hour, by quadrupling the hour to 100 minutes we now get 6 hours in a day, halving the length of a second will now give us 10 hours in a day. We have just decimalised time without significantly changing the base unit. Yeah. The metric system would remain the same, but things will all of course be done in base 12, allthe prefixes still work. I should add this scheme would have put off the millenium bug for about 1000 years. The only thing remaining nondecimal is the year, which short of altering the flight path of the earth will have to remain as is. Of course there are now 275 days or 276 in a year.
Regretfully 5 is no longer a nice number, nor is 10. The only reason we use these though is as our base is 10. Log_10 is now useless, but we add in log_12. Multiplication is easier, i think, I'm not sure of the patterns, but I'm sure multiplication by 3 and 4 is a lot nice. 6 becomes like 5 and is funky. There should be a pattern for 9 and 11 becomes as easy as 9 is currently. 13 is also really easy to multiply by.
Another drawback is that maths will be forced to find a new name for the arbitrary variable. Variables can't just be set to X, that would not work. The multiplaction system should also probably be changed. * could work.
The ultimate plus though is that there are now 20 letters, that respects our base people, beautiful.
I hope you all enjoy that.
Now it's exactly 299792458 m/s. Nothing arbitrary about that at all.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"Britain (i.e. including England) is rapidly moving away from Imperial/"English" units. It's now illegal to price most fruit/vegetables/meat/etc. per pound unless the price per kilogram/gram/whatever is at least as prominent (although there's nothing to stop supermarkets charging per 454 grams). The running joke is that soon we'll get people in court for selling an ounce of marijuana, not because of what it is but because they sold it by the ounce :-)
We still use pints for milk, and pints and half-pints for beer, but most other capacity measures are in metric (actually, I'm not sure what the standard measures for spirits are, they might still be Imperial too).
The only other really common uses of Imperial units I can think of are measuring long distances (we still measure roads and speed limits in miles and miles per hour), and people's heights and weights (somehow it's still easier to visualise what someone looks like if you know they're 6'1" tall than if you know they're 1.85m tall).
Sturgeon was right, 90% of everything really is crap.
This sig no verb.
People in the scientific field (if this guy is even concidered to be in it) are really desperate for publishings...
:
But the Earth isn't a perfect sphere -- it's an oblate spheroid, flattened at the poles -- and every meridian isn't equal because the Earth isn't perfectly smooth, either. So the meter is an average, a compromise -- a figure agreed upon by men, not handed down by nature.
Even if you average the unit, it is still handed down by nature. It's the natural average distance from the north pole to the equator.
Which makes the metric system, extrapolated largely from the meter, arbitrary as well. Not as arbitrary as the yard or the cubit or the rod or the mile, but arbitrary nevertheless.
I guess he doesn't know what arbitrary is...
arbitrary
Determined by chance, whim, or impulse, and not by necessity, reason, or principle.
So he's saying that creating the meter was just on a whim? A bit of a contradiction to the statement a couple sentenced above it "Originally, you see, the metric unit of distance was supposed to be one ten-millionth of the span from the north pole to the equator."
Yes, the actual length of the meter -- compared with what was intended -- is a mistake.
So... who cares? I guess everybody needs to go run and buy a new meter stick that has been updated to the "sattelite measurments" that we can now do today, and you all need to go turn your cars in to get the speedometer adjustet properly. His "news" of innacuracy in the original measurements of the globe are not suprising at all... if you're going to try to publish something... an entire books worth... you need to do it on something that actually matters.
Multiplied by 2, divided by 2.
I'll stake my cat this is in use already.
Is there a cult of metric haters that I'm not aware of?
yes, the inhabitants of the U.S. of A. I remember being taught the metric system (but the non-ISO version with centimeters and liters) in the 70's, because we'd (we as in U.S.A) would all be using it by 1980. But we stubbornly stick to the length of the kings thumb on extended arm to his nose for length (gerd....now pronounced yard) and work a horse could do in 1 second, etc.etc..
Look, any measuring system is going to be arbitrary. This is because the concepts of number and measurement are human concepts invented by the human mind. They have no objective source in nature. They are simply ideas that the human mind uses to understand the world around us. Mathematics is not a science, it cannot be, since it has no subject matter. All any mathematical system can do is manipulate numbers. And numbers have no existence outside the human mind. The fact that humans cannot understand the universe without resorting to number and measurement just points out the limitations of the human mind.
__
The optimist proclaims we live in the best of all possible worlds. The pessimist fears this may be true.
"That fiction, however, would have enormous consequences," Alder says. "If the metric system is today used by 95 percent of the people of the world, it is in no small measure due to the 'grand fiction' that the meter was based on nature. ...
"It would hardly have been adopted everywhere if the French had simply 'made it up.' In that sense the expedition proved to be essential to the 'selling' of the metric system, as well as for all the scientific discoveries it unexpectedly produced."
The Metric system of measurement hasn't been adopted so much throughout the world because of its supposed basis in nature, buddy. It's been adopted because of two things: The world needed a standardized measurement that could be agreed upon *everywhere*, and it needed a system of measurement that was easy to do math with.
Multiples of ten, Sparky. It's a hell of a lot easier to remember 1000 meters in the kilometer than it is to remember 1536 (or however many there are) yards in the mile, and a damned sight easier to do the math.
If you believe everything you read, you'd better not read. - Japanese proverb
Not that it's relevant, but...
Which is heavier? a pound of feathers, or a pound of lead?
.
.
.
The pound of feathers is heavier!
Lead, being a metal, is measured in avurdupois weight; feathers, not being metal, is measured in imperial weight. Differences between an avurdupois pound and an imperial pound, mean that one pound of feathers is heavier!
bits and peace
Nicholas Daley
Leaving out the fact that this author is a crackpot, there is something annoying about the choice of measures that is the metric system. Don't get me wrong, I think the metric system is a heck of a lot better than the imperial measure, but it has room for improvement. The most obvious indication of which is the so called "constants" in any physics equation.
Consider, the equation for calculating the force (in newtons) exerted on a body with mass m (measured in grams) by another body with mass M (also measured in grams) where the distance between the two bodies is d (measured in meters):
F = G m M / d*d
To put it simply, the force exerted on a body of mass m by a body of mass M which are seperated by a distance d is proportional to the combined masses of the bodies divided by the square of the distance seperating them. What's G? G is a constant: 6.7 times 10 to the power of 8.
The constant is required to make the math work out. That's a bit of a hack in my book. If we could combine all the constants in all the formulars together, could we come up with a unit of messure that negated the need for the constants?
Unfortunately, to do this you need a unified theory, and we don't have that. Yet.
How we know is more important than what we know.
The writer of the article is naive to say that the future has not materialized. Only American self-centeredness could ignore that in fact they are the odd ones out (besides England) when it comes to measurements. The rest of the world uses the metric system.
Besides a meter is very well defined it is:
the length of the path traveled by light in vacuum during the time interval of 1/299 792 458 of a second.
Having said that 1 second is more arbitary than the meter, but the author ignores that because no other unit of time exists. (Of course you could say 1 second is the time taken for light to travel 299 792 458 meters)
Exactly. Human scale matters. These measurements evolved and survived because they were useful, not because they were mathematically convenient.
/2 =cup/8 =ounce/2 =tablespoon/3 =teaspoon
An entire order of magnitude is often too great a span. The expression "order of magnitude" which specifically means factor of ten even implies that this is a large difference. That's why our measures evolved as they did, as small integer fractions instead. Well, that & convenient math.
Intrpreting the phrase human scale more literally, my pace is 1 yard, as is the distance from the tips of my fingers to my nose. Excellent for measuring rope, cloth, or string. My wingspan and height, 2 yards, or 6 feet. Granted, most people do not have a pace of exactly a yard, but that's because most people are shorter, and consequently even further from an even meter pace.
I love the metric system when I'm doing calculations that involve lots of conversions, but when I'm foughly planning the addition to my house, it's awfully convenient to pace out the distances in integer yards. When I'm measuring cat5, it's damn simple to stretch it out, nose to fingertips a few times, and look at the leftover and know it's 10 feet.
Fractions are often easier to manipulate in one's head than decimals, especially if one is already using a convenient number like 12 as a base.
I love SI units and the concept of significant figures for chemistry. When I'm cooking, the scale of
gallon/4= quart/2 =pint (a pound of water)
works quite well, and the significance of the figure is implicit in the measurement used as a rule, just like the appropriate amount of torque is implied by the length of the handle on a wrench.
Don't forget decimal time. "The benefits of decimal time are ease of calculation, a single number that can represent an exact time and date, and that can be used by everyone on the planet, or off it." As far as meeting my wife for lunch or calculating my timesheet, those factors are trivial compared with the importance of using a measure that is meaningful relative to the way I use time. Hence, no-one lives by a decimal clock. The French tried for a few years, but gave up.
Being "multilingual" in terms of measurement is a good thing. Different circumstances call for different measures. There are people who use decimal time for technical reasons. Peculiar measures are an easy target, but those arose because they had a particular function. The jigger is a damn convenient measure for liquor. Sure, we could call a jigger a 45 mil measure, but when we do, we lose something. In addition to the convenience of using integer measures with particular meaning, there's a little culture & history carried by these things too.
When that happens, pour me two fingers out of that fifth of bourbon, and I'll put two bits into the jukebox and we can try to talk Esperanto. Oh! Too late. The fifth is gone as a measure of liquor. Well, I can drink from a 750ml bottle.
Don't forget about Megabit and Megabyte (as interpreted by Disk Drive manufactureres vs. everybody else.) That factor of eight is a pain in the ass. We should go to decimal computing.
Assembly is the reverse of disassembly.
according to nist.gov:
The meter is the length of the path travelled by light in vacuum
during a time interval of 1/299 792 458 of a second.
follow the link for the exact definition of a second
(determined by a number of periods of a cesium-133 atom).
i find it odd that nether this slashdot article nor the cnn piece mention these.
Use my userscript to add story images to Slashdot. There's no going back.
Finally! Us short folk will get the same amount of fabric per rod. And my friends can help me build an arc since we'll be able to agree on the size of a cubit! Then again, if one thinks about it, there's something very utilitarian in measurement based on human dimension. Good for guesstimations.
Tell me wise one, how do you measure a 7th of an inch? Show me your ruler.
Now, which every day tasks was you teacher talking about? What is difficult about measuring 20, 30 , 70 or 90 centimeters of something?
Is 6 feet easier to comprehend than 2.4 meters? How easy it is to comprehend 3 and 13/16 feet. ANd can you comprehend 3 meters? Convert that to English system and let me know how clear is that.
And that is not all, apart from shear memorization, how do you realte units of volume and lebght in ENglish system? In the metric system you just keep multiplying. In the English system? A bushel? A gallon? how does that relate to the feet and inches? They don't.
Your teacher reasoning was simplistic, but alas, his problems were small. A good system, like the metric, addresses those small problems and the big ones in an elegant scalable manner easy for anybody toi understand.
Miles, furlongs, feet, inches. Yikes!
IANAL but write like a drunk one.
This is why I enjoy slashdot's science section, everything gets cleared up to perfection.
You can think of your cups, pints, quarts, etc. as powers of 2. Here are the US customary units for your converting pleasure:
2^0: mouthful
2^1: jigger
2^2: jack
2^3: gill/jill
2^4: cup
2^5: pint
2^6: quart
2^7: pottle
2^8: gallon
2^9: peck
2^10: pail
2^11: bushel
2^12: strike
2^13: coomb
2^14: cask
2^15: barrel
2^16: hogshead
2^17: pipe
2^18: tun
I'm actually a little surprised geeks are so metric-happy when we happily use powers of two for all things computer (2^10 bytes=1MB, 2^20 bytes=1GB, etc.)
"Avoid employing unlucky people - throw half of the pile of CVs in the bin without reading them." -- David Brent
Angle - there are very good mathematical reasons for using radians
And no practical reasons for doing so. Quickly, what is a 36-60-90 triangle in radians? Did you give your answer in terms of pi? That's a dead giveaway that radians, as an absolute measure, are pretty darn worthless.
I do woodworking and I have a lot of use for 90 and 45 degree angles. I'll be cutting some 22 1/2s this weekend.
I have discovered a truly marvelous sig, unfortunately the sig limit is too small to contain i
"Why is 6 feet easier to comprehend than 2.4 metres? (actually ~1.8m). "
You've managed to make it hard to comprehend. 2.4 meters is not actually ~1.8 meters.
Integers are simple. Small integer fractions, simple. 1.8 meters is over an inch (2.54 cm) short of six feet. On the other hand, 6.56 feet is too many significant figures for most measures involving a couple of meters or few feet. You've made my point.
Use whatever works. Convert where appropriate, because after all, some of us can do maths, and don't mind converting. You don't like imperial measures? Don't use 'em. Don't call me stupid because I use yards roughing out a housing addition. I'm happy to use meters in a ballistics experiment. (Throwing rocks with a roman sling counts as a ballistics experiment, right?)
Look up a few craftsman's rules of thumb, and you'll find origins of a lot of these measures.
Some of them are obsolete. I hated trying to figure out a person's weight in stone, although in terms of human weight and its daily variations, it makes some sense to use a large increment. I'm glad medicine is measured in milligrams instead of grains. Maybe someday, prescriptions won't be written in latin, too.
I'd generally rather that a craftsman use a measure his trade deems appropriate than try to bend him to a metric rule for my convenience. Imagine you are talking with someone who is complaining that they don't know how much a byte is. You explain how to convert.
I discovered last weekend that my house is built with 2x4 that are actually two inches by four inches. A cheerful surprise, since the 2x4 (standard for lumber in the U.S. was slimmed down at about the time the house was built. Silly, isn't it?
I'm in favor of standardizing on commercial use of the metric system. I'm just tired of hearing that everything else is stupid, and think the arguments for using other measures are interesting. These strange measures carry information. Sometimes that information is obsolete, and merely of historical interest.
Perhaps I'm just arguing because I find it interesting. The arguments for metric are similar to the arguments for Esperanto. I'm afraid I find those arguments dull, since they are few although compelling. On the other hand, each individual measure, be it rod, fathom, mile, carat, stone, degree, or horsepower, has it's own history and supporting reasons for existing. I find each reason to be a bit of history, or accumulated human factors information, or insight into a craft, and interesting.
I love the way the metric system makes chemistry and physics work. I can hardly imagine the horror of trying to do chem without it. A lingua franca is an important idea. The Systeme International is an important lingua franca. Other languages continue to have their place.
Assembly is the reverse of disassembly.
I just read this book a few days ago. The author is turning molehills into mountains.
According to the book, if Mechain had gotten his numbers right, the meter should have been longer by 2 mm. That's right, just two millimeters.
The researchers measured the width of a continent to within 0.2% of the correct value, using 18th-century equipment, in conditions that were far from ideal. (You try carrying survey equipment across a national border during a war, and see how much work you get done.) We should be impressed that they got as close as they did.
Likely reason - lunar cycle, and people finding 4 moon phases easy.
Lunar cycle is still critical for people dealing with the ocean. Fishermen, scuba divers etc.
Also useful for astronomers.
0 degrees - the energy at which a hydrogen atom is at rest. 1 degree would be the energy at which hydrogen is one quantum state higher than rest.
By saying "degrees" I take it you are referring to temperature... but energy is NOT the same thing as temperature, even though they are often linked. I believe you're thinking of something more along the lines of electron-volts (eV). The "volt" is what you'd need to re-define in order to normalize your energy scale with respect to this bound electron.
However, some people might find that saying "the nearest gas station is about 1x10^15 distances away" a tad bit inconvenient. Atoms are pretty "fuzzy" anyway so the only length you can go by is the bohr radius, which is an oversimplification of the actual probalistic structure of a hydrogen atom. But if we want to develop units from the atomic scale, wouldn't it be better to define length as the distance travelled by light in a vacuum during the time it takes hydrogen to "vibrate" once?
As for the hydrogen's rest energy, well that is essentially defined by its mass (times speed of light squared). So maybe it's better to define a hydrogen atom as having a mass unit of 1 and then derive energy from that.
Hmmm.... wait a minute, hydrogen is just a proton and an electron. Electrons have negligible mass compared to a proton. Why don't we just call the mass of a proton "1 mass unit," that makes more sense because the proton is even more fundamental than hydrogen.
If you think that's the best idea, then you're in luck, because that unit of measure has already been invented! The atomic mass! Well, sort of, since a proton has an atomic mass of 1.0073, and when you add the atomic mass of an electron, you get a value slightly higher than the atomic mass of the whole hydrogen atom... damn it. So really, no matter what you do, it's hard to define units that are completely "fundamental." So might as well just make them in terms of stuff that humans can understand, like feet, stones, and most importantly, imperial pints.
-CausticPuppy "Of all the people I know, you're certainly one of them." -Somebody I don't know
I didn't get to read /. late yesterday. Damn. I just had this talk with a friend, and I am wondering on this, if the meter were the exact same length as a yard,do you think that the metric system would have been already adopted in the US?
If brevity is the soul of wit, then how does one explain Twitter?
The thing about 24 hours is that it fits wonderfully with a decimal system. The Babylonians realized that Base-60 number systems were terribly useful, since 60 has so many factors (compare with strictly base-10 measures). If you count the number of heartbeats of a healthy man 60 times, that gives you a minute. 60 more gives you an hour. And, rather amazingly, exactly 24 of those gives you the amount of time it takes the planet to spin around once. But wait, there's more: 365 1/4 of those gives you the amount of time it takes for our planet to orbit the sun, within a single second or two. That the planet's rotation and revolution are so precisely synchronized is a constant source of amazement to me.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
But I never thought about the centrifuge example before. Thanks for the extra info
...scandalizes...
You keep saying that word. I don't think it means what you think it means.
This has been bugging me for a while, and now that it's on-topic I hope someone a little more knowledgable than me will point me in the right direction here.
I'm an American. I love this country and the freedoms that we used to have.
It's all a matter of units.
Energy is measured in units of force x distance. Force is measured in units of mass x acceleration (Newton's second law!), acceleration is velocity per unit time, and velocity (or speed) is distance per unit time. Putting this all together, we see that energy E has units of
mass x distance^2 / time^2
while m has units of mass, and c has units of distance/time. So the equation E=mc^2 makes sense no matter what you pick the units to be.
In SI units, mass is measured in kilograms, distance is in meters, time is in seconds, so speed of light is in meters/second. Energy is measured in kilograms-square-meters-per-square-second, more commonly known as Joules.
If we were to use light seconds and seconds, then the speed of light would be 1, but then energy would be measured in kilograms-square-light-seconds-per-square-second, which is a truly humungous amount of energy (about 10^17 Joules, which is about the same energy released by about 10 megatons of TNT, give or take an order of magnitude). So yes, the "E" in "E=mc^2" would now be tiny because c was 1, but because E is now measured in megatons of TNT the energy is still the same impressive amount. :-)
Too weird? Perhaps.
The Article also gives the following quote;
For a technological society, our logical base for all measures is 10, or whatever the base of our number system is. We have to deal with a incredible range of numbers (quick: how many miles could the people of Seattle drive with the oil spilled from the Exxon Valdez?) and that's much easier to do when everything is a power of 10.
But in nontechnical societies, your needs are at a much more personal level. In these cases you want numbers that are multiples of 2 or 3. That gives you 2 cups per pint, 2 pints per quart, 3 tablespoons to a teaspoon, or 4 quarts to a gallon. (There's actually an archaic meausre between quarts and gallons, so it's 2x twice over.)
That's why base 12 is so widely used in traditional systems. It can be easily deviced into halves, thirds, quarters, and sixths. 60 adds fifths and is the basis for our navigation (360 is 2 x 3 x 60), clocks, and probably other stuff that slips my mind at the moment.
Finally, one important but often overlooked issue is that the Imperial set of measures was called "Imperial" for a reason - it was largely usable across Britain (or the entire UK?). In contrast, pre-metrification the French had a staggering variety of measures that made commerce beyond the village a nightmare. The French had to do something, but the system the British had was good enough to run a global empire.
For every complex problem there is an answer that is clear, simple, and wrong. -- H L Mencken
I think the previous poster meant to say "joints." Each finger (minus the thumb) has three. Four times three = twelve per hand.
:-)
It makes gesturing a number to someone else quite a bit trickier, but at least for counting it works
iSKUNK!
To divide by 3 and multiply by 12 (12/3), you multiply by 4.
Yes, but you have to go to the extra effort of knowing that since you're converting feet to inches, the numerator is twelve, but if you're converting gallons to quarts, it's four. I'm not saying you have to be a genius to keep track of all these conversion ratios; I just think it's less of a hassle to say, "Let's divide by three and be done with it."
Ever worked with floating point numbers?
Ugh. Don't get me started. They're the bane of my existence. Okay, I will concede you have a point that if exact measures are available, you take them, but I really think that the software example you give only further emphasizes my point that in the real world, exact values don't happen.
To take your example of cutting a board, what about the 1/16 of an inch or so that gets obliterated by the saw? I mean, that sawdust has to come somewhere.
Oh, Hell, I give up: You prefer elegance, whereas I prefer simplicity. The ironic thing is that five years ago, I would've been arguing on your side. I guess I'm just fickle.