Why hasn't U.S. gone metric yet?

[bssc]

It sells more tools. My wife has both English and Metric toolsets, depending on whether the equipment was made in the US or France.

 

[SecondCor521]

But didn't Jesus speak English?

Of course He did. He even spoke in red letters.

2Cor521

 

[ladelfina]

Despite a rigorous science educational bkgd. I never cottoned on to metric in daily life, though I have to use it here in Italy for driving, measuring stuff around the house, and for recipes that say 50ml of milk or 120g of flour.

I know weighing dry ingredients, especially flour, is more precise for baking but there is a lot more basic utility for me in using volumes. What happens when your high-tech digital scale's batteries go dead and you don't have a replacement? Good luck!!

The basis of the metric system is just an arbitrary notion concocted by the French, around the same time that they were re-doing their calendar to include months like "Brumaire" and deciding that hours needed to be 2.4x as long. It's not based on anything coherent to me. Whereas the human scale of yards, feet and inches just 'feels' right! Metric may make calculating easier for dummies (but not necessarily, as cantlogin pointed out), but even people who have never used anything else don't seem have an intrinsic notion of a kilometer.

Some Italians were defending metric measurements as inherently better due to their 'scientific' origin and I asked them what a liter was. "Well, it's a kilogram of water, of course!" Ok, and what's a kilogram? "Uh.." They thought miles were "stupid" until I explained that the word mile comes from "miglia" which comes from "mille" (1000) and measured one thousand paces (left+right) in the progress of a Roman legion marching.

The kilogram is sooo much better, being based on some weight of water at a certain volume, the volume being determined by the circumference of the earth as determined in the 1790s? (1/40,000,000th of the polar circumference of the Earth? that's handy!..The meter is now defined as the distance travelled by light in an absolute vacuum during 1/299,792,458 of a second.. also handy!) It's still pretty arbitrary.

For all their "practicality", the Europeans still maintain the A4, B2, etc. system of paper sizes based on the Golden Mean. The dimensions make no particular sense in ANY measurement system (impossible since they are based on an irrational number, the sq.root of 2) so it's really hard to measure things w/r/t the paper; an A4 sheet is around 210x297mm (approx. 8.25 x 11.75 inches).

An: width=2 to the power of 1/4-n/2; height =2 to the power of 1/4-n/2

I don't think it matters what things are based on as long as everyone has the same model. And different models could be better for different things; computers aren't based on the decimal system, but base 2, base 8, base 16 or whatever. Division in 12ths is another common natural human instinct. To me, there's not always inherent superiority in the number 10.

It's an interesting subject.. also because it seems like it's hard to come up with enough common properties of the measurable universe that are not subject to change, or at least change in how they are measured, defined, and maintained. The master kilogram itself is changing in mass and they are scrambling to figure out ways to preserve it!

By definition, the error in the measured value of the IPK’s mass is exactly zero; the IPK is the kilogram. However, any changes in the IPK’s mass over time can be deduced by comparing its mass to that of its official copies stored throughout the world, a process called “periodic verification.” For instance, the U.S. owns three kilogram standards, two of which, K4 and K20, are from the original batch of 40 sister copies[citation needed] of the IPK delivered in 1884. The K20 standard was designated as the primary national standard of mass for the U.S. Both of these, as well as those from other nations, are periodically returned to the BIPM for verification.[13]
Note that the masses of the sister copies and replicas are not precisely equal to that of the IPK; their masses are calibrated and documented as offset values. For instance, K20, the U.S.’s primary standard, originally had an official mass of 1 kg – 39 µg in 1889; that is to say, K20 was 39 µg less than the IPK. A verification performed in 1948 showed a mass of 1 kg – 19 µg. The latest verification performed in 1999 shows a mass identical to its original 1889 value. The mass of K4, the U.S.’s check standard, as of 1999 was officially calibrated as 1 kg – 116 µg. However, it was 41 µg more massive (in comparison to the IPK) in 1889.
Since the IPK and its replicas are stored in air (albeit under two or more nested bell jars), they adsorb atmospheric contamination onto their surfaces and gain mass. Accordingly, they are cleaned in preparation for periodic verifications—a process the BIPM developed between 1939 and 1946 known as “the BIPM cleaning method” that includes steam cleaning, lightly rubbing with chemical-soaked chamois, and allowing the prototypes to settle for 7–10 days. Cleaning the prototypes removes between 5 and 60 µg of contamination depending largely on the time elapsed since the last cleaning. Further, a second cleaning can remove up to 10 µg more. After cleaning—even when they are stored in their bell jars—the IPK and its replicas immediately begin gaining mass again. The BIPM even developed a model of this gain and concluded that it averaged 1.11 µg per month for the first 3 months after cleaning and then decreased to an average of about 1 µg per year thereafter. Since check standards like K4 are not cleaned for routine calibrations of other mass standards—a precaution to minimize the potential for wear and handling damage—the BIPM’s model has been used as an “after cleaning” correction factor.
Because the first forty official copies are made of precisely the same alloy as the IPK and are stored under similar conditions, periodic verifications using a large number of replicas—especially the national primary standards, which are rarely used—can convincingly demonstrate the stability of the IPK. What has become clear after the third periodic verification performed between 1988 and 1992 is that the mass of the IPK lost perhaps 50 µg over the last century, and possibly significantly more, in comparison to its official copies.[14][15] The answer as to why this might be the case has proved elusive for physicists who have dedicated their careers to the SI unit of mass. No plausible mechanism has been proposed to explain either a steady decrease in the mass of the IPK, or an increase in that of its six sister copies and the others dispersed throughout the world.[16] Further, the IPK exhibits an instability of about 30 µg over a period of about a month in its after-cleaned mass.[17] The precise reason for this instability is not fully understood but is thought to entail surface effects: microscopic differences in their polished surfaces, unintentional differences in the cleaning process, and/or differences in the precise nature of the contamination. What is known is that the past assumption that the cleaning process reliably restores the prototypes to their original value is false and that the BIPM’s after-cleaning correction factor is useful only for long-term trends. Scientists are seeing far greater variability in the prototypes than previously believed. Further, there is no technical means available to know whether or not the entire worldwide ensemble of prototypes suffer from even greater long-term trends upwards or downwards because their mass “relative to an invariant of nature is unknown at a level below 1000 µg over a period of 100 or even 50 years.”[14]
The relative change in mass and the instability in the IPK has prompted research into improved methods to obtain a smooth surface finish using diamond-turning on newly manufactured replicas and has intensified the search for a new definition of the kilogram.

Kilogram - Wikipedia, the free encyclopedia

I kinda feel bad for the folks who are dedicating their lives to the SI kilogram. I guess "somebody's gotta do it"..!

 

[ERD50]

ladelfina, you can prefer the english measurement system if you like, but your 'arguments' don't hold much water, not an ounce or a mL, for me.

Knowing that a mile is 1000 paces for a Roman soldier helps you identify with a mile? I don't get any sense of what 1000 paces is w/o actually walking it out, and the variation between an individual and the Roman army 2000 years ago is going to be high. Plus, the way we need to utilize miles today involves converting from feet (5280) and yards (1760). Whether a town is 50 miles away, or 80 kilometers is something I would get accustomed to with use.

You seem to be arguing the 'standards thing' from both sides of your mouth. On one hand, you think it is a problem to have a physisl standard (it is) becuase it varies over time with handling. But then you say, why use the wave length of light as a standard? Well, the wavelength is a physical property that can be replicated in labs across the world, and in space. Yes, we humans can't relate to it, but why does that matter? With regular use, I can grow accustomed to how long a meter is, or a centimeter, or about how many kilograms I can easily pick up as readily as I can a foot, an inch or a pound. I fail to see how one is intrinsically more meaningful. They are going to tend to be arbitrary at some point.

And a liter (and therefore kilogram) is tied to the meter (1L = a cube 1 dM on a side), it isn't totally arbitrary. Even though the meter was originally tied to a non-human scale (equator to pole ÷ 10,000,000 ) it is pretty close to a yard, so it isn't that hard to identify with.

Whether you weigh flour or measure it by volume is a factor in both English and Metric systems.

I'm not giving a centimeter on this one

-ERD50

 

[HFWR]

This topic is causing extreme [-]angstrom[/-] angst...

 

[travelover]

Used to have a friend named "Miles". Calling him "Kilometers" just didn't seem right.

 

[REWahoo]

Yeah. I'm not sure I could get used to the switch from a "foot-long hot dog" to a "30.48 centimeter hot dog". Seems to lose a little something in the traslation.

 

[HFWR]

Yeah. I'm not sure I could get used to the switch from a "foot-long hot dog" to a "30.48 centimeter hot dog". Seems to lose a little something in the translation.

Don't worry, the marketing genii have already shrunk the foot-long doggie to [-]27.94cm[/-] [-]279.4mm[/-] 11in anyway...

What is the metric equivalent to "$hitload"?

 

[Grizz]

At least we can all agree on one thing, -40 degrees C = -40 degrees F, and frostbite happens in under 10 minutes at that temperature.

Every winter we get it for a week or so, and that's why I'm concentrating on my ER goal....to snowbird my life away. Can't wait to have a December tan.

 

[ladelfina]

ERD50.. I didn't think I was having an "argument".. more like a discussion, kinda with myself as much as anyone.. sorry!

After several years I still can't envision "8 cm" and "80km" still means nothing to me, though the latter I can kind of work out by imagining what the speed limit is on the type of road and then calculating the likely driving time. This is, no doubt, a personal defect. For the former, I have no solution; maybe I will tattoo a centimeter mark on my thumb. Perhaps I am peculiar in that my thumb knuckle-to-tip is pretty much exactly 1" so while I am agnostic, in theory, about the basis of all standards since they are all arbitrary, I have a personal soft spot for those based on human beings and not things that are imperceivable to the average person. Maybe a mile is outdated since few Americans walk everywhere but I think it's overall more informational than you allow.

This exchange cracked me up:

After I realized that relativity slowed and speeds up time relative to the frame of reference I realized that time is not absolute. Why would we continue to measure time as the vibration of an atom. Wouldn't we start measuring time by the vibration of a photon? Since a photon is absolute no matter where in the universe it is and it stays constant for that wavelength.

--
be very careful answering that. if you say "photons of blue visable light" then i would ask how you define blue? if blue photons are the photons that make it through some standardized blue filter, then you're back to defining this in terms of the atoms of some material.

--
Why not measure time using as an unit the period of the electromagnetic oscillations taking place in the electromagnetic wave in which we are immersed? Besides that we should now which kind of time interval we measure: proper time or coordinate time.

--
To measure time, you need photons of known fixed wavelength, so that you know the frequency. If you are moving in reference to the source, that changes the frequency (doppler effect), but thats not a problem in atomic clocks. So you use a specific atomic vibration, with a specific energy, to generate the photons of fixed frequency.

--
which photon would you choose as a standard for a unit of time?

To measure cosmological time:
Select a photon sampled from the peak emission intensity of the CMB corrected for the Earth's dipole movement.

Then the universe woul be eternal, and if c is defined constant and used to measure radar distance, the universe would also be static, as in the Jordan conformal frame of SCC.

--
I guess your right about the doppler effect. It just doesn't seem right to measure time with something that changes.

--
You don't get any Doppler effect if you are not moving wrt the source. In metrology, your clock is supposed to be infinitely small and to lie at rest no farther away from your elbow. So, no Doppler effect, of ny sort.

Time measurement

This is almost like the economics argument with my sister (her: consumption fritters away what the economic engine of business creates; me: there's no point for production without the need of others to consume the product). Are we in a world that must be run according to a universal (yet incomprehensible) standard? That could work well in some cases, perhaps many or even most, but for me it's not satisfying in all cases. Can't we (shouldn't we) also be able to live with standards that are 'human-scale'? Do we design our manufactured world to fit an arbitrary (but 'scientific'!) standard or do we design our world based on ourselves as part of it? This is just a philosophical windmill I am tilting at here, I am well aware.

you say, why use the wave length of light as a standard? Well, the wavelength is a physical property that can be replicated in labs across the world, and in space. Yes, we humans can't relate to it, but why does that matter?

The std. US foot equals some factor of the wavelength of light right now. There's nothing special about the meter, in that sense, that the span or the fathom or the pica doesn't, or couldn't, also have.. that's all I'm saying.

Don't get me started with the recipes.. I am sticking to my guns on the volume as being best for most [That was the main aspect of -yes- my "argument" with the Italians about measurement..] I screwed up my cherry liqueur recipe which in Italian called for 500g of 90° alcohol; I read it too quickly and put in 500ml. What wackos write recipes where you have to weigh the liquids!? No big deal in the end but it did tick me off as I was in a 'cranky about Italy' phase.


Did everyone remember to set their greater-than-infinitesimally-small-and-thus-wildly-inaccurate clocks back?

 

[meridiver]

Did everyone remember to set their greater-than-infinitesimally-small-and-thus-wildly-inaccurate clocks back?

Actually, they've changed daylight savings again - according to my calendar, they pushed it back by another week to next Sunday. And the funniest thing was, nobody even noticed. There was nary a word in the news this weekend about it. I think quite a few people will be very surprised next week though.

Why we can't just get rid of standard time and stay on daylight savings all the time is beyond me. Yeah, yeah, the kids will be waiting for the bus in the dark - c'mon, how many kids actually still take the bus at 7AM? And most of them would much rather have the extra daylight after school just like the rest of us. OK - rant off.

 

[cute fuzzy bunny]

Last time they tried that, I was one of the kids waiting for the bus. It wasnt that dark and I didnt have any problem with it, but I still remember the news furor over the PO'd parents.

I'd sure like DST all year round. I can use the daylight at the end of the day a lot more than in the morning. I've already had to tell Gabe a couple of times that we cant go to the park because its too late and almost dark already. Yank that back another hour next week and its gonna be a hassle.

 

[David1961]

If we ever did switch to the metric system, I'd love to watch a football game and have the ref call a 4.572 meter penalty for holding!!

 

[ERD50]

ERD50.. I didn't think I was having an "argument"..

ladelfina, sorry from ME, 'argument' was a poor choice of words - I just meant it in a 'point-counterpoint' way, not in a 'put up your dukes' way.

All these complex issues on the measurement of time, and like others point out, we can't even get this crazy DST thing right. My VCRs are all goofed up because they have a built in calendar for the time change. That seems crazy, wouldn't the signal from the broadcast TV tell them if it was DST or not? Anything I try to do to 'fix' it will just be 'broken' when DST actually does change.

Now, if they just cancelled time changes, I can turn off the changes in my VCR - that should work. Crazy.


Hmmm, maybe I need to send my VCRs into space for a week?

-ERD50

 

[Zipper]

I think most Olympic measurements are metric.

 

[TromboneAl]

It doesn't matter what the measurement system is based on, the important thing is the convenience of it's use. It's simply not convenient to have 12 inches to the foot, three feet to the yard, and 5,280 feet to the mile. But we're very good at dividing and multiplying by ten. It makes no difference whether it's based on the size of your whatever (9 inches!), or the size of the earth.

As for metric measurements having no meaning for you, that would change very quickly once you started using them.

 

[Zipper]

You need to get over yourselves.

Your grandchildren WILL be metric.

If we can do it, so can you!

 

[ladelfina]

they pushed it back by another week to next Sunday.

OH! Here they didn't change it. We "fell back" yesterday. Ain't these standards great? Now I have to get confused about when I can call people in the States.

It's not a matter of using the metric system, I used it every day, all day, for years, then I changed career paths and used point and picas all day, every day, for years. (And I go all day speaking a language that's not English, so it's not like my brain is ENTIRELY sclerotic -- Al, no piling on unless you can tell me off the top of yr. head what 9 inches is in centimeters to the first decimal place!!)

I guess to me it's more a matter of what may seem more appropriate for what one is dealing with.


I find it natural to have 6ths, 8ths, 12ths or 16ths.. to me it doesn't HAVE to be divisible by ten. Sorry! I like 12ths because you can divide easily by 2,3,4 and 6. With 10 you only have 2 and 5. I find that limiting. Next time you order a pizza, ask them to make it a decimal pizza and cut it in 10 pieces!

 

[REWahoo]

Now I have to get confused about when I can can people in the States.

Only if their performance isn't up to standard, then only after you've given them a verbal, followed by written, warning telling them specifically what they need to improve in order to prevent being terminated.

Then you can can them.

 

[ladelfina]

ooops! That's what I get for posting between yoga class and a late supper (frozen paella - 750g for the two of us).

 

[bssc]

Of course He did. He even spoke in red letters.

2Cor521

I noticed that too.

 

[bssc]

Last time they tried that, I was one of the kids waiting for the bus. It wasnt that dark and I didnt have any problem with it, but I still remember the news furor over the PO'd parents.

I'd sure like DST all year round. I can use the daylight at the end of the day a lot more than in the morning. I've already had to tell Gabe a couple of times that we cant go to the park because its too late and almost dark already. Yank that back another hour next week and its gonna be a hassle.

We don't observe DST in most of Arizona because who wants another hour of 40+ degree heat.

 

[Meadbh]

I'd sure like DST all year round.

Then you should definitely NOT move to Saskatchewan!

"Most of Saskatchewan has not observed daylight time since 1966 and stays on Central Standard Time all year round".

CBC News In Depth: Daylight Time

 

[Meadbh]

Kilos, Shmilos....

I'm a baby doctor. I can look at a baby and guess its weight to the nearest 100g. But I have no idea how many pounds and ounces the same baby would be.

So it seems very odd to me to have the following conversation even with parents who are healthcare providers!

Me: Congratulations! You have a lovely baby girl, she weighs 3.5 kg and all's well now.

Parents: Yes, but how many pounds and ounces is she?

Me: Let's see. 3500/454 = 7.71 lbs. 0.71 pounds is 0.71 * 16 ounces to one pound.....or 11.36 ounces.....so she's just under 7 lbs, 11 and a half ounces.

Parents: Oh good! How tall is she?

Me: We haven't measured that yet. We were busy saving her life.

 

[ladelfina]

don't forget the Chinese, who have one vast time zone.

Meadbh, thanks for reminding us, though.. of more important yardsticks.. erm meter sticks.