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Why Does the US Cling To Imperial Measurements?
PhunkySchtuff writes "As one of only three countries on Earth that hasn't converted to a metric system of units and measurements, there is a huge amount of resistance within the US to change the status quo. Whilst the cost of switching would be huge, there is also a massive hidden cost in not switching when dealing with the rest of the world (except for Liberia & Burma, the only other two countries that don't use the metric system) With one of the largest organisations in the US, the military, using metric units extensively, why does the general public in the US still cling to their customary system of units?"
And what this means, in reality, is that if you're doing work for the Federal Government, you do all your work in Imperial Units, and then convert them to Metric. So you don't actually get "standard" metric sizes... you get "standard" Imperial sizes with metric units labeling them.
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What is even worse, is scientific shows like Mythbusters use BOTH systems. Usually they use metric, usually it's F but sometimes it's C. Weighs usually pounds, but they also have used (kilo)grammes. Distance is usually inches and feet, but when bouncing a baseball they were measuring the bounce in cm - while other parts of the same experiment were using inches and feet.
There is no consistency, and that alone can give rise to errors. It doesn't really matter whether one uses cm or inches, or C or F as long as it's consistent. Forget to write down the unit once, and it's guesswork that's left. Have a thermometer with both scales - oops which scale were we using again this time?
Its much more intuitive for an advanced civilization to have a base(x) counting system with measurement standards being built of the counting system. so aliens are more likely to understand a metric system better than imperial. Aliens should be able to understand the true nature of mathematics and use that to classify sizes, not the average size of a foot.
However i disagree with America conforming "just because". we haven't even moved to a base 10 timing metric yet, who are we to judge?
The thing is, even if they are both based on arbitrary fundamental measures, SI units are self-consistent, while imperial measurements are not. So a lot of arbitrary constants are required in the US that are not needed elsewhere.
You are missing the point. The main argument for the metric system is NOT because it is standard, regardless of what TFA says. The reason we should switch to the metric system is the same that the rest of the world has already -- it simply makes a whole lot more sense. Everything is base 10, and if you know what the basic unit of measurement is you can very easily figure out how to go between units simply by moving a decimal place. Imperial measures, on the other hand, are totally psychotic. 12 inches to a foot, 3 feet to a yard, 5,280 feet to a mile. It is the type of nonsense that we would expect to see in Dr. Seuss story, not it real life.
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Yes some of those rules of thumb break, but you end up with different and new rules of thumb instead. For instance, 100km/h is a pretty standard speed on many roads (don't be daft, they wouldn't convert 60 mph to 96 km/h ... they'd make it 100). So the distance to your destination in 100s of km is the number of hours until you get there (e.g. 300km = ~3 hours, 425 km = ~4 hr, 15 min). I personally use that rule of thumb all the time when driving.
Also wouldn't approximately 1 foot be approximately 30 cm (why convert exactly to 30.5 if you're only talking 'approximately' in the first place?) 30 cm divides cleanly by 15, 10, 6, 5, 3 and 2. Kinda nice actually.
Metric is a heck of a lot easier to explain than imperial.
Lets see, 2.5 cm per inch, 12 inches per foot, 5 foot per fathom, but its also 5280 feet per mile...and its 3 feet to a yard, which is kind of like a meter, but not quite...
As opposed to simple powers of 10 for metric. If we could today snap our fingers and have everything switched over, with no conversion costs, it would be a no brainer.
Yes, there are some.
Sometimes it's a matter of scale -- for instance, units based on electron-volts are useful when you want to talk about the energy in a single photon or electron, or things on that scale, while the Joule is a much more accessible unit when you're at the scale where metric units make sense -- can't get much simpler than a kilogram meter per second. It's not just a matter of a nano-Joule vs a Joule -- it's a matter of the electron-Volt being based on how elementary particles actually behave, while the Joule is based on fairly arbitrary (but convenient) metric units.
Sometimes it's a matter of who is using the unit, and what they're using it for. I often talk shit about the Kilowatt Hour -- Watts are Joules per second (energy per time) and the Kilowatt Hour is Kilowatts per Hour (power per time, where power is energy per time) -- so you end up back at energy. The Kilowatt hour is basically a really clumsy multiple of the Joule -- or at least, it's really clumsy if you're dealing with Joules, which would imply you're dealing with physics and engineering. The fact that electrical appliances are rated in watts means that a kilowatt hour is still quite convenient if you want to know, say, how much it's going to cost to run a box with a 250-watt power supply 24/7, or a 700-watt, 70-inch HDTV for a few hours a day, or how long it'll take for a CFL to pay for itself, and so on.
Degrees Celsius vs Kelvin. Kelvin is a lot more useful if you need to do actual calculations -- again, physics/engineering -- but the difference between 273 kelvin and 313 kelvin doesn't really mean as much as the difference between 0 degrees Celsius and 40 degrees Celsius.
Or angle measures -- degrees are much easier for humans to work with than radians when just trying to figure out the angle, but radians are a much more natural angle to do any sort of calculations in, especially since they technically aren't even units. You can do crazy things like take that 7200 RPMs your hard disk spins at, convert it to radians/second, and multiply it by the radius of your hard disk in whatever units you want, and you'll get the linear velocity of the edge of that disk in those same units.
That is, 45 degrees is a lot easier for humans to learn than pi/4 radians, but if you know you've got pi/4 radians, that's a lot easier to apply to almost anything.
I could go on, and that's just off the top of my head, from what is theoretically a freshman physics course.
None of this, by the way, is a justification for imperial measurements. Those are just retarded. Unfortunately, I haven't been able to learn Celsius for temperature -- I know what 40 degrees Fahrenheit feels like, but I have no idea (until I convert it) what 5 degrees Celsius feels like. Still, I'd be the first to suggest any shift towards better units -- maybe while we're at it, we can fix the whole minute/hour/day weirdness and start dividing the day by powers of 10 instead.
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But I admit it doesn't matter whether you call it centimeter or inch or measure the distance by the eyebrow length of the great communicator Ronald Reagan.
Call it the freedom fighting anti-communist inch of the greatest empire on earth, if you wish. And make it twice as long as every other country's unit.
Doesn't really matter.
What matters, is the fucked up unit system within the imperial system.
Let's say you want to convert 1/8 inch rainfall to gallons per square yard? Yes, doable, sure. In the metric system however it's just counting zeros and shifting a decimal point.
A meter has 100 centimeter, so a square meter has a 100x100 square centimeter, or 10000. Easy, just count zeros. Liters in a cubic meter? Easy. Kilograms per square centimeter to tons per square meter? Easy, just counting zeros.
But square inch to square feet? Square miles? floz to gallon?
And if that isn't bad enough, add all the competing units used in the US. Air pressure is a different unit when the air is in the atmosphere or in the tire. For energy, there are different units depending on whether it is an air conditioner, a furnace, a car, what company I get the energy from, and whether the second Friday after Lincoln's birthday falls on a full moon.
The difference to the metric system is not, that inch and cm are different. The beauty of the metric system is that you have a consistent system. And that's why scientific calculations are usually done in metric and the result is then transfered back to imperial, so the US public won't get worried that the French took over, communists gained control of the class room, or that their politicians betrayed the greatest conceivable nation on earth.
But that's just familiarity. If you grew up under a metric system, were taught metric in school and saw metric measurements in everyday objects (other than the 2 liter soda bottles...) then you'd be able to visualize 1 kilometer just as easily as you could visualize 1 mile today.
The issue here is that it will take a generation (or more) to make that transition, during which time all the big nobs will feel increasingly isolated as they're more quickly overtaken by these 'new math' thinkers. Inertia is comforting.
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They are self-consistant and use a fixed base. Imperial units do not use a fixed base. They're expressed in decimal, sure, but fractions of an inch are measured in fractional powers of 2 (exceptr for mils, which are measured in thousandths), inches are measured in base 12, nails are measured in base 16, hands are measured in base 4, palms are measured in base 3, feet are measured in base 3, yards are measured in base 22, chains are measured in base 10, furlongs are measured in base 8, miles are measured in base 3.
Imperial units are "natural" measures - you will find that most (if not all) natural phenomena will work out to an exact integer number of some measure or other. This made them great when making exact measuring devices was extremely difficult. Far and away easier to use a measuring device that occurs all around you. If you're sneaky, you can even use Imperial Units from different countries. (A foot in Belgium is not the same distance as a foot in America.)
Some of the units I've given above are now only used in specialist cases. Since people tend to go from yards directly to miles, you now have yards measured in base 1760. (This would obviously be useless if you were using a tally sheet of any kind, 22s, 10s and 8s are far more practical and far more easily counted manually.)
However, none of these units are remotely useful EXCEPT when measuring natural phenomena (which never happen in convenient SI units). Trying to program a computer in eleven different base systems would be horrible. Trying to get it bug-free would be impossible. Trying to get anything remotely intelligent to display would be ludicrous. Sure, computers can convert between Imperial and SI and then do all the SI internally. And this would be useful how? You're adding extra layers of complexity on the human end (which is naive at best) and adding extra layers of complexity into the code (which is downright stupid and irresponsible).
I was one of the few generations in England to be taught both Imperial AND Metric systems in school, simultaneously. This was in the transition period in the early 70s (before half the current Slashdot readership was born). I also had to learn both the decimal and pre-decimal currencies. Trust me, modern English schoolkids are missing NOTHING by being wholly metric. Well, so long as they understand the history as well. The history is valuable because without it you cannot understand historic descriptions accurately. The numerical values would make no rational sense without the context in which the units were created.
Of course, things not making sense has never stopped US schools or school boards in the past, hence the proliferation of creationist textbooks in science classes.
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> This made them great when making exact measuring devices was extremely difficult.
No. As you pointed out yourself: A foot in Belgium is not the same distance as a foot in America
People were forced to create exact measuring devices for all units. Else, they will be cheated. There's a reason why every old church in Europe has circles etched on their front-side. People could hold bread to them to verify they were bought the correct amount. Etc pp.
> However, none of these units are remotely useful EXCEPT when measuring natural phenomena (which never happen in convenient SI units).
Celsius comes to mind.
> then do all the SI internally
Last I checked, computers used base 2, not SI units.
I agree with you and the GP. In school in the '70s, I learned about the metric system / SI. PBS even had an entire series called "The Metric System"... I still remember part of the theme song. As time has passed and wholesale conversion didn't happen, I realized something: for everyday private life, SI has no clear advantages over the US customary system. There is nothing compelling about a kilometer or a meter that makes it a clear and necessary replacement for the mile or foot. The same goes for the kg vs. the pound (I know, that's comparing mass vs. weight, but if we don't need to allow for gravitational fluctuation then the difference is meaningless), or the liter vs.the quart. Yes, it's easier to convert from liquid measure to linear-cubed in SI, but you know what? Do you know why almost no one knows how many gallons are in a cubic foot? Because no one cares. It sounds nice on paper but for everyday life that's not a conversion people need to make. Yes, using the same system as the rest of the world makes commerce easier and I do believe that all Americans should at least have a passable understanding of SI and how its units compare to US customary. But in this instance the expense, disruption, and anti-convenience of a mass conversion at the personal level trumped the benefits to international commerce.
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