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Teter
09-14-2005, 10:56 AM
i bet this has been addressed in the past but i want to put it out just so i can feel better. just had another run in with a co-worker in the company kitchen and ended up trying to explain to her that life would be better if we were to adopt the metric system. she had no better argument than "i just don't get it".

i used to work on an oil rig in international waters. this rig had about 25% of its population from countries other than the US. the metric system was used fluently by all (people would have a hoot watching sunday "american" football")

question: so, what is keeping the metric system down? and why?

(i've heard that the stonecutters have somthing to do with it)

muttrox
09-14-2005, 11:12 AM
It is very painful to convert. Although the metric system is much simpler and easier than what the US uses now, it is very hard to convert from what we have now to metric.

xbuckeye
09-14-2005, 11:12 AM
I think the metric system is eventual. People my age, who went to college in the '90's or later, are almost exclusively taught metrics. People at work talk to me about pounds and I reply "what are these pounds of which you speak?" As we grow older and take over the world...err...replace the dinosaurs in charge...umm..I mean..come into positions of leadership, we will bring the metric system with us.

What is bringing it down? The dinosaurs in charge that weigh things in pounds
Why? they don't know the freedom and liberation of the metric system not having the privelege of access to the superior educational institutions of our time.

Anaamika
09-14-2005, 11:15 AM
It would be extremely expensive to convert. Every sign, every measurement would have to be changed. One of my friends (Noone Special) had a good idea, although I'd never tell him...to make every new sign in metric, and not replace the old ones. But I hate metric. *grumble grumble* :)

Teter
09-14-2005, 11:18 AM
i understand the resitance to change (fear what you don't understand) but our science tries to be metric. it just seems odd that we are the world hold-out.

we certainly have more important things to deal with but i feel like a twit trying to explain oz, cup, pint, quart, gallon to anyone not familiar with the american system.

maybe the US will become so powerful that all others in the world will want to emmulate us and do away with their silly base 10 system in favor of our "thingy fur measurin' stuff"

Tuco
09-14-2005, 11:18 AM
It is very painful to convert. Although the metric system is much simpler and easier than what the US uses now, it is very hard to convert from what we have now to metric.

Britain is getting there without too much hassle, fuel is supplied in litres, goods are sold in kgs, etc., the only things that are imperial are road signs and people still tend to measure themselves in stone and feet/inches but I know lots of people who measure themselves in metric.

BwanaBob
09-14-2005, 11:22 AM
Oooh, a nitpick I love to share.

Although I embrace the metric system, weight is typically (and erroneously) expressed in kilograms. Wrong! Weight is a force and force should be expressed in Newtons.

The Kilogram is a unit of mass.

Oddly enough, pounds are correctly used in the "old system"; they are units of force.

Balthisar
09-14-2005, 11:24 AM
Even when you go into metric Canada, you see feet and pounds and quarts all over the place. Hell, at a Japanese company (metric) in Ontario (metric) that I used to do business with, all of the measurements were English. Centigrade and kilometers seems to have taken hold, though.

Hell, even here in Mexico, everyone has a vague concept of while a "milla" (mile) is, and purchase their locally produced and bottled milk in gallons ("galones").

I used the metric system all the time. I'm fluent in both and can use them equally well. About the only thing I hold out on its "miles per gallon" instead of "litres per 100 km" and measurements for recipes. Oh, and acreage. Hectares just don't do it for me.

Back to Mexico, they use centigrade for temperatures, but most of the recipes are teaspoons, tablespoons, and cups! You get into metric measurements for weights, though.

Okay, as to why we don't use them in the United States? Well, there's not really any compelling reason to. Yeah, for some people who want to use English recipes it'd be nice if everything were metric in the USA, but for the most part, why change what works? Don't come back saying "metric's easier" or "the English system is hard." It doesn't matter. We get by with it as it is, and there's nothing compelling enough to make people want to change. The most basic reason is there's no need to. Oh, wait -- commercial use, you say? We do that already when we need to. Why should you weigh yourself in kilos at home just so I can use an M6 nut at work?

Xema
09-14-2005, 11:27 AM
The US alread uses the metric system to a considerable (and increasing) extent. Most (all?) new automobiles use metric fasteners and for a shop not to have (and use daily) metric tools would be almost unthinkable. Hardware stores will reliably stock metric tools and fasteners.

In aviation weather broadcasts, temperatures are often given in degrees C.

So the unofficial transition is well underway.

Teter
09-14-2005, 11:30 AM
The US alread uses the metric system to a considerable (and increasing) extent. Most (all?) new automobiles use metric fasteners and for a shop not to have (and use daily) metric tools would be almost unthinkable. Hardware stores will reliably stock metric tools and fasteners.

In aviation weather broadcasts, temperatures are often given in degrees C.

So the unofficial transition is well underway.

so, the metric system is insidiously taking over the world :p

Fridgemagnet
09-14-2005, 11:32 AM
It is very painful to convert. Although the metric system is much simpler and easier than what the US uses now, it is very hard to convert from what we have now to metric.
True, but the rest of the world has managed to do it somewhere along the way. It's just ingrained conservatism that keeps the US imperial. Go on, take the plunge. You know you want to.

It's a right pain in the arse for us European electronic engineers, as we usually have to lay out our printed circuit board designs on grids measured in thousandths of an inch (thou British English, mil US English) because Americans insist on specifying chip packages in FRIGGING INCHES! All the sensible metric pitches never quite line up.

IIRC, metric/imperial mixups have been responsible for more than one NASA clusterfuck. Wasn't that also the reason for the slight chamfer on the Apollo rockets near the Command Module? A 'fudge factor' section to align two separately built rocket sections that should have been the same diameter, but weren't?

I was among the last British generation to be taught in both metric and imperial. I remember thinking how ridiculous it was that someone should decide that an inch was two and a half centimetres long! It's now illegal in the UK so sell foodstuffs in pounds and ounces, it must be metric. But road signs are still in miles, speed limits are in MPH, and junction markers are spaced at 100 yard intervals, not 100 metres. So we've still to catch up to Eire and the rest of Europe.

GorillaMan
09-14-2005, 11:36 AM
Oooh, a nitpick I love to share.

Although I embrace the metric system, weight is typically (and erroneously) expressed in kilograms. Wrong! Weight is a force and force should be expressed in Newtons.
Surely it's the other way around, and people express their mass using kilograms, and simply mis-title the measurement? (Seriously - after all, nobody claims you actually lose weight in a descending lift)

GorillaMan
09-14-2005, 11:37 AM
It would be extremely expensive to convert. Every sign, every measurement would have to be changed. One of my friends (Noone Special) had a good idea, although I'd never tell him...to make every new sign in metric, and not replace the old ones. But I hate metric. *grumble grumble* :)
'Extremely' expensive? I don't see that one. Sure, there'd be some cost and some hassle, but as has been pointed out, Britain has managed to switch to metric measurement for all food with little problem, and half of Europe managed to switch currencies, so such things certainly can be done.

BwanaBob
09-14-2005, 11:42 AM
I stand by my claim.

using Metric units:
Weight is measured in Newtons.
Mass is kilograms.

When people talk about their weight they mean "weight" because you will hear conversations about how "On the moon you weigh 1/6 of what you weigh on Earth". And they would be correct. But a persons mass doesn't change.

So Joe Metric who has a "mass" of 80 kg weighs 784 Newtons on Earth but weighs 130.6 Newtons on the moon. He still has a mass of 80 kg.

But Jim Imperial who weighs 180 lbs on Earth does indeed weigh 30 lbs on the moon.

Leaffan
09-14-2005, 11:46 AM
After, what, 25 years of the metric system in Canada we are still converting. For example, it not uncommon for us to say "Nice day. The temperature's going to be 28 degrees. Oh, and I checked the pool. It's reading 80."

And we don't even blink at these kinds of mixed readings. We understand completely. Weird, "eh?"

GorillaMan
09-14-2005, 11:47 AM
When people talk about their weight they mean "weight" because you will hear conversations about how "On the moon you weigh 1/6 of what you weigh on Earth". And they would be correct. But a persons mass doesn't change.
This is irrelevant. They're not talking about the same thing as when they talk about working off the excess flab. If they were really talking about weight in this context, then they would genuinely consider living at the top of a mountain to be a way to lose weight. But they don't, they would say that you weigh the same as at sea level, so they're really talking about mass.

Anaamika
09-14-2005, 11:47 AM
'Extremely' expensive? I don't see that one. Sure, there'd be some cost and some hassle, but as has been pointed out, Britain has managed to switch to metric measurement for all food with little problem, and half of Europe managed to switch currencies, so such things certainly can be done.
How about I just don't want to?

But I don't dictate policy, so wwhat does it matter what I think?

CookingWithGas
09-14-2005, 11:51 AM
I. . .a persons mass doesn't change. . . .But Jim Imperial who weighs 180 lbs on Earth does indeed weigh 30 lbs on the moon.OK, so what is the unit of mass in the English system?

BwanaBob
09-14-2005, 11:51 AM
This is irrelevant. They're not talking about the same thing as when they talk about working off the excess flab. If they were really talking about weight in this context, then they would genuinely consider living at the top of a mountain to be a way to lose weight. But they don't, they would say that you weigh the same as at sea level, so they're really talking about mass.

Duh. Why do think I said it was a nitpick? People mistakenly say weight (which varies) instead of mass.

BwanaBob
09-14-2005, 11:53 AM
OK, so what is the unit of mass in the English system?

Believe it or not, its the "slug".

scr4
09-14-2005, 12:01 PM
Back to Mexico, they use centigrade for temperatures, but most of the recipes are teaspoons, tablespoons, and cups! You get into metric measurements for weights, though.
Teaspoon and Tablespoon are Metric-based units, defined as 5 ml and 15 ml respectively. Even the US government uses these definitions for food labeling purposes.

IMO the main reasons English units prevail in the US are:

The US is a fairly isolated and self-sufficient nation. (Isolated in the sense that most people and many companies don't regularly deal with other countries.) Most information and products are either produced within the US, or designed specifically for the US market.
Americans have, in general, more skepticism towards their own government and towards foreign influences than most other people.
American government botched their Metric campaign by emphasizing conversion factors ("to convert centigrade to fahrenheit, multiply by 9/5 and add 32") rather than encouraging people to acquire a feel for the new units ("20 degrees is a nice warm day, 30 degrees is a really hot day").

Xema
09-14-2005, 12:12 PM
30 degrees is a really hot day
More like a nice warm day. (Surely in Alabama it must take something closer to 40 to be "really hot".)

scr4
09-14-2005, 12:21 PM
More like a nice warm day. (Surely in Alabama it must take something closer to 40 to be "really hot".)
Whatever. You know what I was trying to say.

Balthisar
09-14-2005, 12:34 PM
Teaspoon and Tablespoon are Metric-based units, defined as 5 ml and 15 ml respectively. Even the US government uses these definitions for food labeling purposes.D'oh!("20 degrees is a nice warm day, 30 degrees is a really hot day").More salt in the wounds, but man, 30 degrees is a nice, cool day here!

groman
09-14-2005, 12:40 PM
You are also going under the mistaken assumption that metric system is just inherently better.

Yes, it's better if you're trying to compare measures or calculate using measures because it is essentially base 10. However, the measurements don't tend to be nearly as useful in every day life.

I.e. the metric system is useful for everything but measurement :)

For example, in foods, a gram is too little to be meaningful and a kilogram is too big. An ounce and a pound however are very convinient.

In making crafts or tools, again, an inch/foot combo is a lot more convinient than the cm/mm combo. Mainly because of size.

In general, imperial system tends to be divisible into things that it historically evolved to divide into, 3's, 4's, etc. Dividing by 10 is a useful feature of the metric system, but it's not as universal. Metric is just not as natural.

Groman

P.S. I'm a 21 year old immigrant from a metric country and I'd much rather use american system than metric.

Sal Ammoniac
09-14-2005, 01:01 PM
This is way into Great Debates territory, but I'm going to offer a defense of the English system -- at least as it pertains to feet and inches. In woodworking, which I do a certain amount of, I find the English system vastly superior to metric, and not incidentally, much more intimately tied to a traditional aesthetic view that relies on proportionality. For example, any given number of inches can be cut in half, and halved again, and again, and again, and again, and each halving will correspond to a line on your ruler. Try that with metric, and pretty soon you're into fractional millimeters, and you're squinting at the tiny little identically sized lines on your ruler, trying to figure out where the hell you are.

So maybe the answer here is that Americans cling to the English system because certain parts of it make sense to them -- I mean, on a rational level, not just a familiarity level. (And I don't see why we can't use both systems. For scientific/industrial use, use metric; for everything else, English.) But I think we should reject out of hand the notion that metric is simply superior because it's based on tens.

(On preview, I see that some of the same points are being made by groman. Consider this as seconding his views.)

Shagnasty
09-14-2005, 01:10 PM
I too was just going to post that 'feet' and 'inches' (but especially feet) are superior to metric units of length. Considering these are some of the measurements that are used most often day to day by regular people, it is not good advertising.

Giles
09-14-2005, 01:14 PM
(On preview, I see that some of the same points are being made by groman. Consider this as seconding his views.)
I'm a person who has moved in his lifetime from the Imperial system to the metric system to the US-customary system, and I really like metric over the alternatives.

As far as carpentry goes, Australian carpenterrs and builders work consistently in millimetres, and I'm sure it makes their work easier. Since a saw cut is about a millimetre thick (for a hand saw -- it's thicker for a power saw), you never need to work in fractions of a millimetre. And calculatons are generally easier, e.g., to build a 7-shelf cabinet, it's easier to divide 2400 mm by 7 to the nearest mm than to divide 8 feet by 7 to the nearest 1/16 of an inch. OK, I get 343 mm in a couple of seconds mental calculation, and what, 1 foot, 1 inch, then what's 5/7 to the nearest 1/16 -- I think I'll give up of that, it looks like about 3/4. Now I've got to work out the multiples of 13 3/4 inches to mark off my shelves, which is a bit harder than multiples of 343 (especially if your calculator doesn't handle fractions).

scr4
09-14-2005, 01:19 PM
For example, any given number of inches can be cut in half, and halved again, and again, and again, and again, and each halving will correspond to a line on your ruler.
I don't know much about woodworking, but do you never have to cut a given number of inches into 3, 5, 6 or any other number that isn't a power of 2?

I do work with mechanical drawings all the time, and everything is in decimal inches. It's worse than metric because English tools and parts (drill bits, bolts, etc) are in fractions of inches, and you end up having to convert between the two.

Crandolph
09-14-2005, 01:41 PM
I think the metric system is eventual. People my age, who went to college in the '90's or later, are almost exclusively taught metrics.

But college grads are a distinct minority in the US; most other Americans aren't encountering kilos unless they're getting cocaine shipments.

robcaro
09-14-2005, 02:00 PM
I am from the US, but live in Colombia where everything except Gasoline is metric. Gasoline is in gallons. Really, metric is not difficult. You get used to it quite fast.

09-14-2005, 02:13 PM
20 degrees is a nice warm dayYou ain't a 'bama born boah, are ya. Brrr.

09-14-2005, 02:16 PM
[Most] Americans aren't encountering kilos unless they're getting cocaine shipments.Now, now. Don't forget the emerging popularity of 9mm guns.

I'm not sure what this says about American culture...

RealityChuck
09-14-2005, 02:17 PM
Metric is fine, though Fahrenheit is a much better temperature scale for everyday use. It just happens to roughly mark the extremes of temperature that people are likely to encounter and is thus much better in determining how the weather stacks up.

Teter
09-14-2005, 02:35 PM
Metric is fine, though Fahrenheit is a much better temperature scale for everyday use. It just happens to roughly mark the extremes of temperature that people are likely to encounter and is thus much better in determining how the weather stacks up.

?????????????????????????

that sounds like a matter of perception

Gary "Wombat" Robson
09-14-2005, 02:40 PM
I remember learning to drive in Colorado (U.S.) in the 1970's. There were dual-unit signs (miles & kilometers) springing up all over the highways. Now, everything's just miles again. It's like we converted halfway and gave up.

For those griping about the "convenient sizes" of English units, you're just using the wrong metric units. Groman says grams are too small and kg are too large. Try hectograms. About 3-1/2 ounces. Great unit. Shagnasty thinks inches and feet are better measurements. For day-to-day use, maybe mm are too small and meters too big, but centimeters are quite convenient, and decimeters are about equivalent to hands (perfect for measuring horses ;) ).

Okay, that was partially in jest, because people resistant to metric don't want to learn the in-between prefixes, but what's the big deal with this "too small" stuff? So what if you have 56 grams instead of 2 ounces? They're still both perfectly good units.

Bytegeist
09-14-2005, 02:58 PM
I remember learning to drive in Colorado (U.S.) in the 1970's. There were dual-unit signs (miles & kilometers) springing up all over the highways. Now, everything's just miles again. It's like we converted halfway and gave up.

There's still a dual-unit sign somewhere outside of Knoxville, Tennessee, on I-40. About 12 km outside in fact, if I remember the sign right. But you hardly see those otherwise.

Sal Ammoniac
09-14-2005, 03:06 PM
As far as carpentry goes, Australian carpenterrs and builders work consistently in millimetres, and I'm sure it makes their work easier. Since a saw cut is about a millimetre thick (for a hand saw -- it's thicker for a power saw), you never need to work in fractions of a millimetre. And calculatons are generally easier, e.g., to build a 7-shelf cabinet, it's easier to divide 2400 mm by 7 to the nearest mm than to divide 8 feet by 7 to the nearest 1/16 of an inch. OK, I get 343 mm in a couple of seconds mental calculation, and what, 1 foot, 1 inch, then what's 5/7 to the nearest 1/16 -- I think I'll give up of that, it looks like about 3/4. Now I've got to work out the multiples of 13 3/4 inches to mark off my shelves, which is a bit harder than multiples of 343 (especially if your calculator doesn't handle fractions).

I don't doubt that Australian carpenters are able to work consistently in millimeters. It's all what you're used to, of course. That said, I don't find your example particularly compelling. Obviously if you start with 2400 mm, you can divide nicely by seven, but what if you're stuck starting with 2000 mm? Dividing by seven, you get 285.7 mm -- hardly an easy figure to work with. And your observation about the width of the saw cut escapes me altogether.

Beyond proportionality, I find the English measurements on the ruler easier to take in at a glance. I can find 13 5/8 much more readily than I can find, say, 33 cm, 7 mm. This has to do with the way the increments of the inch are stepped off on the ruler: a full-size line for the inch, a half-size line for the half inch, etc.

My point is that from a usability perspective, you can argue, as I am doing here, that the English linear measuring system is superior to the metric for certain purposes. Why abandon it then? Just because everyone else has? I think American contrariness is serving us well here.

billfritter
09-14-2005, 03:12 PM
If I were king, I'd get people shifted over in just a few short years.

Everyone has been taught the metric system in school, for 50 years, but always taught it wrong.

It's always been taught in math class as a way to justify multiplication of decimal constants.

In real life, there is no math in the conversion - You don't convert, you re-measure. Or, mostly, just read the new measurement off the product.

Right now, 2liter bottles have the oz. in parentheses. Cans have the ml in parentheses. Nobody actually has to read either one. They look at the container and know what it is.

So, to change weights to metric, on food you just put the opposite number in the parentheses. No calculator required.

If you pull up to a gas pump in Canada and the digits start climbing, you don't care if its litres or gallons, but just the dollar amount. And you don't care that it's Canadian dollars, because either you have that much cash to cover it or you must charge it whatever the number. Conversion doesn't enter in. And you don't ever need to convert litres and currency to shop for gas. You just pick the station with the lowest price on their sign.

So, you should teach metrics by printing a tiny chart with the 3 or 4 things that most confuse tourists today. But without using the old units at all. For example, for temperature, instead of charting Celsius vs. Fahrenheit or the coversion formulae of the math class, you just list about few key temperatures, the one where you can sunbathe, where you put on a sweater, where you see frost on the lawn, and that's about it. Just those few will tell you how to dress after hearing the weather forecast. Nothing else needs a number. The teapot boils when it boils, no conversion needed.

Stranger On A Train
09-14-2005, 03:13 PM
The US alread uses the metric system to a considerable (and increasing) extent. Most (all?) new automobiles use metric fasteners and for a shop not to have (and use daily) metric tools would be almost unthinkable. Hardware stores will reliably stock metric tools and fasteners.Heh...not in engineering we don't. The only reason some (but certainly not all) American cars use metric fasteners is because many components are manufactured abroad and are in common with other, non-American cars. (General Motors used to be particuarly annoying about this, interchanging metric and SAE fasteners wherever it randomly suited them.)

There's more to swtiching to metric than just changing a few measurements and switching road signs; dials, gauges, test fittings, and so forth are all calibrated to English units. Standard hydraulic and pneumatic fittings are made to SAE specs and are not interchangable (and in fact, many foreign-build hydraulic tools and equipment are forced to use SAE-standard fittings for compatibility). Standard building materials and raw metal stocks are all made to English dimensions, and unless you are Catepillar or John Deere and can order entire mill runs of material, you are not going to be able to order metal sheet in metric thicknesses. And every year the problem is compounded, as more equipment is manufactured to our increasingly antiquidated specification.

I used to work at a construction equipment manufacturer (telescopic material handlers) when the Engineer Manager got the bright idea that we were going to build our new flagship machine line in all metric--metric fasteners, high pressure metric hydraulics, metric engines, even specially formulated metric-thickness high strength corrosion resistant metric steel. :rolleyes: This lasted only so long as the team of purchasing agents and engineers (of which I was thankfully not one) reported how much it would cost to build such a machine; the conservative estimate was about an order of magnitude greater than building a machine out of standard material stock and SAE-spec powertrain and fasteners. Not to mention all of the extra tools we'd have to buy (or have the assemblers buy) in order to continue operating.

The reason we don't--and until the Post-Industrial Morass finally wipes out manufacturing and engineering in this country, won't--switch to metric is simple: inertia and cost, both of which are prohibitive difficulties.

As for people who "hate" metric; WTF? What is there to hate about it? It is a different--and frankly, much more consistant--system of measurement; one which doesn't contain anachonisms such as ergs, British Thermal Units, horsepower, rods, slugs, drachms, hogsheads, pennyweights, acres, perches, chains, Imperial vs. Standard bushels, gallons, short tons vs gross tones, et cetera, and all the accompanying, obfuscating, and unmemorable conversion factors required. Any student of science or engineering knows that calculations using metric measurements are a hell of a lot less prone to being farked up by some misapplied conversion than the anachronistic measurements of the English system.

Stranger

Giles
09-14-2005, 03:22 PM
I don't doubt that Australian carpenters are able to work consistently in millimeters. It's all what you're used to, of course. That said, I don't find your example particularly compelling. Obviously if you start with 2400 mm, you can divide nicely by seven, but what if you're stuck starting with 2000 mm? Dividing by seven, you get 285.7 mm -- hardly an easy figure to work with. And your observation about the width of the saw cut escapes me altogether.
My point about the thickness of a saw cut is that in casrpentry you don't need to measure finer than that (just as you don't need to measure finer that 1/16 of a inch, which is a bit larger than 1 mm). So you don't work with fractions: if your division gives you 285.7, then you work with 285 or 286, just as you would not work with 13 7/256 of an inch. (1/256 of an inch is almost exactly 0.1 mm).

The calculations are all easier when you work with one unit, and the plans don't even need to show the unit if it can be assumed this way. With the American system, you need to calculate in 1/16's, inches and feet.

Fridgemagnet
09-14-2005, 03:23 PM
I'll admit the imperial system does feel more natural, and indeed many measurements were standardised in very organic ways originally:

Inch = width of the king's thumb (or, at a pinch if you weren't the king, your own thumb)
Foot = The length of a foot of someone with a large foot
Yard = chin-to-outstretched-finger-tip
Acre = The area one man and one horse could plough in a day

...and so on.

I'll admit to using feet and inches for trivial woodwork, but for more accurate joinery I'll use metric.

There is a natural feel to metric units too, if you look for them. They were cunningly designed so that originally 1km was 1/40,000th of the circumference of the earth, 1cc of water weighed 1g, and 1 l of water weighed 1kg. The French estimated the earth's circumference wrong when they did the original survey, so the metre has been redefined somewhat, but the density of water neatness comes in handy.

The vegetable plot I rent is measured in rods. That's OK, but I want my high tech stuff in metric already.

bouv
09-14-2005, 03:32 PM
Believe it or not, its the "slug".

There's also pounds-mass. Yes, there is a unit of mass with the same name as the unit of force. IIRC, it's both a holdover from when there was no distinction between force and mass, and so that you CAN actually convert between pounds and kilograms. Since pounds-force and kg measure two different things, one cannot technicall equal a given amount of the other. Yes, you can do a unit conversion that eliminates that pesky aceleration factor of pounds force, but you still don't have a given amount of pounds equaling a given amout of kilograms, you just have a given amount of pounds equal to the force thast a given amount of kilograms will provide in earth gravity.

So along comes Mr. Pound-mass, who uses the same conversion factor that one would use to go from pounds-force to kg, so now you CAN have a given amout of pounds equal a given amount of kg.

The tricky part is when you try to get the weight of an object in pounds-force, if its mass is measured in pounds-mass. They are the same number, and the equation is just Newton's second law (F = ma) but with the dimensionless constant, gc introduced to basically eliminate the fact that otherwise a pound-force would be about 32 times higher than a pound-mass. So to go from pounds-mass to pounds-force, you have:

W = g/gc*m, where g is the gravitation constant, equal to 32.2 ft/s, and m is the objects mass in pounds-mass.

Confusing? You bet your ass it is!

Cheesesteak
09-14-2005, 03:34 PM
i bet this has been addressed in the past but i want to put it out just so i can feel better. just had another run in with a co-worker in the company kitchen and ended up trying to explain to her that life would be better if we were to adopt the metric system. I think this is where arguments pro-metric invariably fall apart. The suggestion, for instance, that Celcius is better than Fahrenheit. Does it really matter a whit in my day to day life that water freezes at 0 and boils at 100? Is calling a really hot day 35 degrees super easy when calling it 95 is hard? Cooking a roast at 350 is just trouble but 175 is simplicity itself.

That doesn't make sense.

Similarly, using miles rather than kilometers to plan a trip isn't exactly a hardship. Using cups and partial cups, tablespoons and teaspoons to cook is fairly straightforward, a bit of 3rd grade arithmetic will get you through. Even inches and feet don't really cause us that much pain, it just takes a bit of getting used to

I think anyone can see how metric is a boon for manufacturing, where conversions are constant and critically important. Around the house, it's just not a big enough deal to claim that life would be better if I switched.

MikeS
09-14-2005, 03:38 PM
Teaspoon and Tablespoon are Metric-based units, defined as 5 ml and 15 ml respectively. Even the US government uses these definitions for food labeling purposes.
Really? (http://www.google.com/search?q=1+tablespoon+in+milliliters&start=0&start=0&ie=utf-8&oe=utf-8&client=firefox-a&rls=org.mozilla:en-US:official) I was always taught that there were three teaspoons in one tablespoon, sixteen tablespoons in a cup, four cups in a quart, four quarts in a gallon.

FWIW, Wikipedia (http://en.wikipedia.org/wiki/Tablespoon) says that the way I was taught is the "traditional" way, but it also mentions the federal redefinition.

Foaming Cleanser
09-14-2005, 03:39 PM
Canada adopted the metric system officially in 1970 (http://members.shaw.ca/gw.peterson/metric.html), but it was too late for me. I still can't instinctively picture anything in metric: I have to translate a kilometre into a fraction of a mile before I know for sure whatever the stated distance is. Temperatures mean nothing, other than 30 is hot so 25 is nearly so. The Celsius scale is too course a measurement, anyway. There's too big a difference over one degree, let alone five.

I know what 30 or 20 or 7 miles to the gallon means as soon as it's uttered. But 12.3 litres over 100 kilometres? WTF!?

A trip to the States is like hopping into a time machine. I instinctively know the highway speeds, the distance to travel and how long it will take to get anywhere (but figuring out gas mileage in the States has always been goofy. What is this quaint U.S. gallon thing the locals insist on using?)

My two nephews were educated in metric and grew up with it. They know nothing else, other than intellectually. Neither of them know, care to know or have any reason to know that 90 is hot (since we're still breathing, it must be Fahrenheit). When in the U.S., they have to translate everything to metric to get a feel for how fast they are travelling and the time it will take to get somewhere.

So, yeah, the dinosaurs have to die before Fahrenheit stops being used on old-fart radio stations. And since I'm among the youngest members of the last generation educated in imperial (metric was an afterthought), all things being equal those radio stations will use Fahrenheit for a long time yet.

Bytegeist
09-14-2005, 03:42 PM
[ The metric system ] is a different--and frankly, much more consistant--system of measurement; one which doesn't contain anachonisms such as ergs, ...

Ergs are metric, actually. They're the unit of energy in the CGS system of units. One erg = 10-7 Joules.

Plynck
09-14-2005, 03:43 PM
As someone who lives in the US, and vacations in Canada every year, I would say that it isn't that difficult for the average person to adapt to the metric system in every day life. Some things are more descriptive (millimeters of rain rather than inches), and some are less (degrees of temperature).

I work in an engineering firm, and I agree with Anaamika, the cost of converting does bear a stiff price, especially with historical engineering information. Holding on this due to cost isn't like holding on immediate environmental concerns; no real harm is done by not taking action right now. (Oh yeah, the Hubble... :smack: )

BTW, Massachusetts Department of Transportation chose to adopt metric, and eventually caved in and went back to Imperial units (I believe that groman was first here in using this correct term for the system that US uses now). Massachusetts USGS maps were the only ones in the US (that I know of) in 1:25000 scale rather than the 1:24000 scale in every other map (presumably in order to conform the intended (and abandoned) conversion to metric).

That said, I don't see much reason to change. George Orwell said it best in 1984:

" 'E could 'a drawed me off a pint," grumbled the old man as he settled behind his glass. "A 'alf liter ain't enough. It don't satisfy. And a 'ole liter's too much. It starts my bladder running. Let alone the price."
But, if the oil companies see the profit in it, you can bet that we will be buying liters of gasoline :rolleyes:

Don't know if this warrants a thread to itself, but while we're on the topic of the metric system, for those who advocate complete conversion:

Why not convert time to metric? Why convert all other means of measurement, and then have to deal with 60 seconds per minute, 60 minutes per hour, 24 hours per day? And then all those pesky weeks and months? Days and years are both quantifiable; any thing else is arbitrary.

Chronos
09-14-2005, 03:45 PM
Using cups and partial cups, tablespoons and teaspoons to cook is fairly straightforward, a bit of 3rd grade arithmetic will get you through.OK, you're making cookies. But it's for a big bake sale at your kid's school, so you're making ten times the amount in the recipe. It's kind of annoying to measure out 10 teaspoons of baking soda, though... Would be much easier to use a measuring cup.

So, how many teaspoons are there in a cup? Do you know? I sure don't. But I can tell you how many milligrams there are in a gram, or milliliters in a liter.

xbuckeye
09-14-2005, 03:55 PM
But college grads are a distinct minority in the US; most other Americans aren't encountering kilos unless they're getting cocaine shipments.
We were taught metrics in high school too, I just put my college time in there to peg my generation. And it is the college edumikated folk that usually get to make the decisions.

I forgot to mention 'til others did that I can do temperatures in both scales, 22-25 is room temp, 37.5 is body temp, 100 is boiling, 0 is freezing, 4 is your frige and everything else is relative.

Myglaren
09-14-2005, 03:59 PM
I took some timber to be cut down at our factory sawmill, the dimensions being 75.6cm x 105.5cm.
The saw operator coudn't do it, he only worked in millimetres!

Giles
09-14-2005, 03:59 PM
" 'E could 'a drawed me off a pint," grumbled the old man as he settled behind his glass. "A 'alf liter ain't enough. It don't satisfy. And a 'ole liter's too much. It starts my bladder running. Let alone the price."
An imperial pint is about 0.568 litres, so if that 10% difference is the worst thing in that old man's life under Big Brother. ... And there's a bigger difference between the Imperial pint and the US pint (0.473 litres) than there is between an Imperial pint and a half litre.

seosamh
09-14-2005, 04:00 PM
Ireland has been offially(-ish) metric for ages now, with road distances shown in kilometres (except on the traditional, white finger-posts, which still show miles...). However, until 20th January this year, all speed limits were in miles per hour. Confusion or what?

Beer, I am glad to say, is still served in pints (as in the UK), thanks to a get-out clause in the relevant EU Directive.

I started school in 1964 and was largely taught in Imperial - I still have somewhere an old arithmetic book for under 11's printed in the 50's which contains horrors like "divide £12-18-8 by 5/6½". Thank f*ck those days are over!

If someone tells me that they weigh 56 kilos, it takes me ages to work out what they are in stones (for American viewers, a stone is 14 pounds) before I can call them a fat git or a skinny runt. And if they said they were 1 metre 75 tall, I wouldn't have a clue if they were a giant or a midget. Nor would I have the faintest idea how big a field would be if someone told me it was 43 hectares - but equally, I'd be in the dark if it were 6 acres.

But talk to anyone over here of generation just below mine - say, someone born in the mid-60's even - and they haven't a clue about Imperial stuff. It's easy to convert: just start teaching nothing but metric in schools and in about 30 years, everyone still using Imperial will have retired or died. Sure there'll be about 20 years of confusion, but that's a small price to pay - unless you work for NASA, I suppose...

Cheesesteak
09-14-2005, 04:00 PM
3 teaspoons in a tablespoon
4 tablespoon in 1/4 cup

for 10 teaspoons of baking soda, I'd do 3Tbs + 1tsp. Mostly because spoons are easier to use with baking soda. You could also do 1/4cup - 2tsp

Metrically, it would be 50ml, which is pretty handy, but 9x is 45ml and 8x is 40ml, which has to be made up of various combinations of 15ml and 5ml spoons anyway, unless metric cooks have a massive variety of cups and spoons in every possible 5ml increment.

Easier metrically? Maybe somewhat, but as long as you can stuff my first two lines here into your brain, imperial isn't that tough, even in the odd circumstance where you're really sizing up a recipe.

Valgard
09-14-2005, 04:16 PM
When I was getting my civil engineering degree in the 1990s most classes were still taught in English units. Then for one of my reinforced concrete classes the professor taught in all metric units. It took 5 minutes of "An apple is about .1kg. That's one Newton of force. Turn it into applesauce and spread it over a card table, which is about 1 meter on a side. That's one Pascal of pressure." and that was it, made no difference to how the class was taught or what we learned except that the mental arithmetic was easier.

I'm with Giles on the woodworking; I do it for a hobby and working with mixed powers of two is a major PITA. Lessee, 1 7/16 inches plus 3/32 inches, minus 1/8 inch saw kerf, then divide by two...too easy to screw up. Now imagine that your tape measure and meter stick and saw fence and whatnot are marked in millimeters and your tablesaw blade is 3mm thick (2mm for a thin-kerf blade). No fractions, math is much easier. I've seen the owner of one American cabinet shop talking about how he switched everything over to metric and everyone is much happier, far fewer math errors.

And I don't buy that "pounds are more convenient than kilograms" - "a pound" is more convenient than "half a kilo" of sugar? Does that mean that "two pounds" is less convenient than "one kilo"?

Stranger On A Train
09-14-2005, 04:17 PM
3 teaspoons in a tablespoon
4 tablespoon in 1/4 cup

for 10 teaspoons of baking soda, I'd do 3Tbs + 1tsp. Mostly because spoons are easier to use with baking soda. You could also do 1/4cup - 2tsp

Metrically, it would be 50ml, which is pretty handy, but 9x is 45ml and 8x is 40ml, which has to be made up of various combinations of 15ml and 5ml spoons anyway, unless metric cooks have a massive variety of cups and spoons in every possible 5ml increment.

Easier metrically? Maybe somewhat, but as long as you can stuff my first two lines here into your brain, imperial isn't that tough, even in the odd circumstance where you're really sizing up a recipe.You've never worked in a commerical kitchen, have you? Being the math whiz :rolleyes: that I am, I found myself always having to do conversions for the baker's assistant at one shop. "So, how much is 3-1/3 pounds by 6? And how much is 4-3/4 tsp by 12? What is that in cups?" It makes one wonder if someone doesn't make a baker's slide rule.

Stranger

Xema
09-14-2005, 05:13 PM
...doesn't contain anachonisms such as ergs, British Thermal Units, horsepower, rods, slugs, drachms, hogsheads, pennyweights, acres, perches, chains, Imperial vs. Standard bushels, gallons, short tons vs gross tones, et cetera
All those delightful anachronisms! Surely the world will be a duller (though no doubt a more efficient) place when (if?) these disappear.

"I'll give up my rods, poles & perches when they pry them from my cold, dead hands."

Stranger On A Train
09-14-2005, 05:23 PM
All those delightful anachronisms! Surely the world will be a duller (though no doubt a more efficient) place when (if?) these disappear.As anachronisms, they are indeed delightful. As working units, they are a pain in the ass.

I like playing with slide rules and sextants, but if I have to calculate something or measure my position quickly and accurately I'd rather use an electronic calculator and an GPS receiver

Stranger

Mangetout
09-14-2005, 05:33 PM
Britain is getting there without too much hassle...That's because the conversion is being achieved by government statute and our typical reaction to such legislation is to grumble, but comply. This may not hold true for other countries (the term 'cold, dead hand' springs immediately to mind).

GorillaMan
09-14-2005, 05:45 PM
I wonder how many people who express a desire to retain the 'acre' as a familiar unit can readily explain its subdivisions? ....

AHunter3
09-14-2005, 06:19 PM
You know, we covered all this just the other (http://boards.straightdope.com/sdmb/showthread.php?t=1672)....

...wow, umm, I guess it's been longer than I realized :eek:

Balthisar
09-14-2005, 06:25 PM
I wonder how many people who express a desire to retain the 'acre' as a familiar unit can readily explain its subdivisions? ....
Happily! There's the 1/2 acre, the 1/4 acre, and though not all that useful in the real world, the 1/8 acre.

Gorsnak
09-14-2005, 06:47 PM
I wonder how many people who express a desire to retain the 'acre' as a familiar unit can readily explain its subdivisions? ....
Where I come from (western Canada), measuring land in anything other than acres is a pain in the butt. Everythings surveyed in sections (sq mile) and quarter sections. An acre is a chain (16.5") on a half mile, so you can just measure your field on one side of the quarter section and know how big it is (assuming it stretches all the way across, but that's usually the case). I like metric fine, but with the way the land was surveyed it will be a long time before people stop giving directions in rural areas in miles.

Sal Ammoniac
09-14-2005, 07:26 PM
I'm with Giles on the woodworking; I do it for a hobby and working with mixed powers of two is a major PITA. Lessee, 1 7/16 inches plus 3/32 inches, minus 1/8 inch saw kerf, then divide by two...too easy to screw up. Now imagine that your tape measure and meter stick and saw fence and whatnot are marked in millimeters and your tablesaw blade is 3mm thick (2mm for a thin-kerf blade). No fractions, math is much easier.

But see, this is where you're making a compromise for easier math -- according to Giles, you make this work by just throwing out any fractional millimeters. Now, I don't know about you, but if a miter joint in cabinet work had a half millimeter gap in it, I'd feel like the work was absolutely subpar.

I'm hardly saying that the metric system produces inferior work. It comes down to preference and habit in the end. But the idea that the metric system is superior for this sort of thing hardly has a consensus in this country -- as this thread shows. Obviously, for industrial or scientific use, particularly where other countries are involved, metric has a lot to recommend it, as plenty of posters have pointed out.

Chronos
09-14-2005, 08:43 PM
...Imperial units (I believe that groman was first here in using this correct term for the system that US uses now)Incidentally, this is wrong. The U. S. does not use imperial units. We use American units, and I don't think there's any other accurate name for them. There is a system of units called imperial, which does bear some superficial similarities to American, but they're not the same. An imperial pint, for instance, is 25% larger than an American pint (and likewise for quarts and gallons), and I'm pretty sure the teaspoons and tablespoons are different too. Which is another advantage of metric: Whenever anyone in the world says "liter", they all mean the same thing.

Sal, yes, for some work, millimeter precision wouldn't be good enough. In that case, you use tenths of millimeters, or micrometers, or femtometers, or whatever level of precision you need. Of course, one can also work in thirtyseconths of an inch or one-thousand-twenty-fourths of an inch or whatever is needed, but it's a lot easier to add 5 mm + 4.3 mm than it is to add 3 1/8 inch plus 5 17/64 inch.

racer72
09-14-2005, 08:59 PM
but it's a lot easier to add 5 mm + 4.3 mm than it is to add 3 1/8 inch plus 5 17/64 inch.

Takes me just as long to add the metric and fractional, especially when you use dividable denominators. At Boeing, everything is built in inches, we use 10ths and 100ths instead of 8ths and 16ths, it is just as easy to add as any metric measurement. Some tolerances are meausured in 10,000ths. And try to find a metric tape measure, the Home Depot near me doesn't even carry them. The tool department manager said they use to carry them but they didn't sell. I switch to the metric system the day they pry my Craftsman 9/16" wrench out of my hands.

racer72
09-14-2005, 08:59 PM
but it's a lot easier to add 5 mm + 4.3 mm than it is to add 3 1/8 inch plus 5 17/64 inch.

Takes me just as long to add the metric and fractional, especially when you use dividable denominators. At Boeing, everything is built in inches, we use 10ths and 100ths instead of 8ths and 16ths, it is just as easy to add as any metric measurement. Some tolerances are meausured in 10,000ths. And try to find a metric tape measure, the Home Depot near me doesn't even carry them. The tool department manager said they use to carry them but they didn't sell. I switch to the metric system the day they pry my Craftsman 9/16" wrench out of my cold dead hands.

racer72
09-14-2005, 09:03 PM
Hmm, that's weird. Clicked submit reply, got the 404 error, page not found. Clicked back, made a quick change and clicked submit reply, now I have 2 posts.

Valgard
09-14-2005, 09:05 PM
But see, this is where you're making a compromise for easier math -- according to Giles, you make this work by just throwing out any fractional millimeters. Now, I don't know about you, but if a miter joint in cabinet work had a half millimeter gap in it, I'd feel like the work was absolutely subpar.

I'm hardly saying that the metric system produces inferior work. It comes down to preference and habit in the end. But the idea that the metric system is superior for this sort of thing hardly has a consensus in this country -- as this thread shows. Obviously, for industrial or scientific use, particularly where other countries are involved, metric has a lot to recommend it, as plenty of posters have pointed out.

And the same miter with a 1/64" gap would be about as bad :-) Frankly that comes down to angular errors, not linear ones.

What I'm getting at is that I think people will make fewer mistakes if everything is in whole numbers, and the smallest basic metric unit in this case (1mm) is pretty close to the level of accuracy that is achieved. If you want to work to 0.5mm that's great (better eyes than me!), but that still means your measurements tend to end in 0.0mm or 0.5mm, no biggie.

Look at it this way, if the basic unit of measurement was the Thingy, where one Thingy = 1/32", then you could pretty much do everything in whole numbers. Suppose you have to add 1 7/16" to 3/4" and subtract 1/8" and then divide by two...I dunno about you but I have to convert it all to 16ths and then do the math, so 23/16+12/16-2/16 = 33/16, divided by two equals 33/32nds.

If you were measuring everything in Thingies to begin with it'd be a little easier - 46+24-4, divided by 2, gives 66/2 Thingies or 33 Thingies. Minimal use of fractions, converting to a common denominator, etc. If you work to 1/64" tolerances and the first bit was actual 1 13/32" then you'd wind up with 65/2 Thingies thus 32.5 Thingies. Simple decimal. Your ruler wouldn't even have a "3/4 inch" mark on it to begin with, just 24 (Thingies).

That's fine for woodworking, but how about if the scale is much larger...battleship hulls, or Ringworlds? I can convert from millimeters to kilometers by just changing exponents. To go from Thingies to miles I'm going to have to break out the calculator (32x12x5280? Yuck). In this case simple powers of ten is far better than the hodgepodge of factors in English units. It may have made a great deal of sense in days of old to define an inch as "the length of three contiguous dried barleycorns" and the foot as "the length of his majesty's right foot from the callus on his heel to the tip of his middle toe, after that hangnail is taken care of" but we don't need to hang on to that.

When the scale gets really tiny everything goes by powers of ten anyhow, metric because that's how it was designed and English because no chip designer wants to convert back and forth between 1/32,768th of an inch and 1/524,288th of an inch.

Sorry, that's a very long-winded way of saying that the smallest unit should match the level of accuracy desired (thus making everything come out to whole numbers) and that converting up and down the scale should be simple. Metric does this quite easily. My "Thingy" system does the first but not the second since we're still tied to the other English units.

OK, off to buy some metric rulers and tape measures and put my money where my millimeter is :-)

GorillaMan
09-15-2005, 01:09 AM
An acre is a chain (16.5") on a half mile
...but a chain is 22' (assuming you're talking about what I think you mean)

Malacandra
09-15-2005, 03:21 AM
An acre is one chain (22 yards) by one furlong (220 yards). Once you've driven your team for 220 yards they're about ready for a rest while you turn the plough around, and when they've been up and down enough to plough a 22 yard strip, they've had it for the day.

Princhester
09-15-2005, 04:16 AM
I don't doubt that Australian carpenters are able to work consistently in millimeters. It's all what you're used to, of course. That said, I don't find your example particularly compelling. Obviously if you start with 2400 mm, you can divide nicely by seven, but what if you're stuck starting with 2000 mm? Dividing by seven, you get 285.7 mm -- hardly an easy figure to work with.

Perfectly easy, yes. It's about halfway between the 285.5 and the 286 mark on the ruler. Near as dammit.

Besides which, any system is going to have awkward divisors. But I can work out 2843mm less the end panel widths of 24mm each divided by 7 on a calculator in seconds. In fact, it doesn't matter what combination of subtractions and divisions you throw at me, if it's too hard to work out in your head you can use a calculator.

When you get to an awkward and complex division/subtraction in imperial, what do you do? A whole lot more keystrokes I'll warrant.

Beyond proportionality, I find the English measurements on the ruler easier to take in at a glance. I can find 13 5/8 much more readily than I can find, say, 33 cm, 7 mm. This has to do with the way the increments of the inch are stepped off on the ruler: a full-size line for the inch, a half-size line for the half inch, etc.

Not inherently, only because you're used to it.

A metric ruler has cm marks and mm marks. plus the 5th mm mark between each centimetre is usually bigger. Much less chance for confusion because there are fewer different marks.

TokyoBayer
09-15-2005, 05:11 AM
Transplanted American living in almost metric country. After being here for a number of years, I pretty much have an instintive feel for metric dimentions now, including temperature, distance, lenghts, etc. Japan does most things metric, but keeps their old measurements for some things: office space (1 tsubo = 3.3 m2) apartment rooms are often measured by the number of tatami mats (180 cm X 90 cm), although they are going towards smaller mats. Irratating as all hell.

We moved office, and I would talk to real estate agents who would give the space in tsubo which I would have to convert to square feet for the head office to understand.

It's easier to switch "cold turkey;" if you have the other unit there as well, then you just rely on the one you're familiar with.

Fridgemagnet
09-15-2005, 05:13 AM
Incidentally, this is wrong. The U. S. does not use imperial units. We use American units, and I don't think there's any other accurate name for them.

Fair point. Strictly speaking Imperial is the old British system, and our pints and gallons are a tad different from their US counterparts. Our inches used to be slightly different too, but they're aligned now. But I'm still amazed that a country can send people to the moon in feet and inches, and shocked that Boeings are still specced in a similarly archaic fashion.

Just to redress the balance, I should point out that the US \$ was the first decimal currency, where \$1=100 cents.

GorillaMan
09-15-2005, 08:49 AM
An acre is one chain (22 yards)
Feck, yes, 22 yards not 22 feet :smack:

The Chao Goes Mu
09-15-2005, 08:54 AM
I'm all for conversion to metric. I can't stand and never could stand imperial measurement. I remember in high school chemistry when we were only allowed to use metric. I thought I had died and gone to heaven. It doesn't take long to get used to and to start to actually relate those numbers into the reality of everyday life. It becomes easy to know that 20 C and 68 F both equal pleasant days. Tell me it in millimeters and I can grok it. I never fully understood imperial anyway. Even today it confuses me. Yards, rods, acres. I still cannot effectively picture in my mind what an acre is. Give it to me in metric and I will understand. It's math done easily in the head.
I'm no carpenter but when I'm doing projects on my house, I use the metric part of the ruler for myself but then give my GF the imperial measurement for her use.

It's all relative and I think that it's easy to train the mind to adapt to a new system.

Meh, that's just my .02

robby
09-15-2005, 11:05 AM
Incidentally, this is wrong. The U. S. does not use imperial units. We use American units, and I don't think there's any other accurate name for them...

Chronos is correct in that the U.S. does not use imperial units. However, the generally accepted name for the system of units used in the U.S. is the "U.S. Customary System (USCS)." This is the official term used by, for example, the National Council of Examiners for Engineering and Surveying (NCEES).

There is least one other difference between imperial and USCS, in that the USCS uses the pound-mass for the unit of mass instead of the slug. As mentioned previously, working with the pound-mass introduces the correction factor gc. This factor creeps into all manner of equations, which makes engineering calculations of any complexity an absolute nightmare.

For example, kinetic energy: KE = mv2/2gc, with KE in (ft-lbf). It gets progressively worse when you start dealing with fluid equations.

The metric (actually SI) is much easier to use.

Plynck
09-15-2005, 02:39 PM
Chronos is correct in that the U.S. does not use imperial units. However, the generally accepted name for the system of units used in the U.S. is the "U.S. Customary System (USCS)." This is the official term used by, for example, the National Council of Examiners for Engineering and Surveying (NCEES).I humbly stand corrected thanks to both of you. What is interesting is that the software I use for civil engineering and surveying (Softdesk/Land Development Desktop for those playing at home) specifically references these units as "Imperial Units". Of course, they are only referencing units used in linear (or square or cubic) measurement, and not for volume or mass, so they might be technically correct if USCS and Imperial are in agreement on these units. Nevertheless, it is always good to know the correct terminology.

Drumming fingers here...

Why not convert time to metric? Why convert all other means of measurement, and then have to deal with 60 seconds per minute, 60 minutes per hour, 24 hours per day? And then all those pesky weeks and months? Days and years are both quantifiable; any thing else is arbitrary.Well, the response to this has been nil. (Kinda expected to hear from, say, an SDSAB whose name elicited thoughts of time...) Was the lack of response due to pained embarassment over a stupid question, or has this been discussed to death? Should a day be "metricized" to ten hours? I don't happen to think that it is feasible or likely, nor would I particularly want to see this, but I think as much of an argument could be made for this as adopting the metric system of measurement. I also know that the definition of a day as a unit is worthless when leaving Earth, and I've read enough Brian Greene to be confused when even talking about time, but it would seem that this would be the case with any unit of time, whether we based it on a day or on the rate of decay of a radioactive isotope. Is this worth a separate thread, or should I just let this die?

Chronos
09-15-2005, 03:38 PM
OK, I guess I have to answer that now. Any system of measuring time will have a problem, in that days and years are both rather essential units for human life, and there is not a nice tidy number of days in a year. So a total metrification of time is doomed to failure. The best we can do is to pick one unit of time and use that, and let days and years be whatever they are. And this is more or less what we do. We take the second as the metric unit of time (originally based on the day, of course, but it's now defined in terms of a resonance of a particular atom, and the day is considered a measured quantity), and use that unit for everything metric. And then we have these other two units, the day and the year, that we're just stuck with regardless.

GorillaMan
09-15-2005, 03:46 PM
There's no contradiction in retaining current measurements of time and a uniform use of SI units (robby is quite right to emphasise that these are what we're talking about, not some vague 'metric' phenomena)....because the SI unit for time is the second! That we choose to group these into sixties isn't particularly important, any more than the choice of grouping kilograms by their thousand into metric tons.

Sal Ammoniac
09-15-2005, 03:55 PM
Interestingly, the same people who brought you the metric system (the French revolutionary government, post 1789) tried to do just what Plynck mentions, namely metricize time. The day would be divided, from midnight to midnight, into 10 periods, each of which would in turn be divided into 10 subperiods, and so on, until you attained the smallest measurable increment of time. Each 30-day month would be divided into three ten-day periods, while the year would have 12 30-day months, with five or six intercalary festival days to make up the difference between that and the solar year.

Stranger On A Train
09-15-2005, 04:39 PM
The best we can do is to pick one unit of time and use that, and let days and years be whatever they are. And this is more or less what we do. We take the second as the metric unit of time (originally based on the day, of course, but it's now defined in terms of a resonance of a particular atom, and the day is considered a measured quantity), and use that unit for everything metric. And then we have these other two units, the day and the year, that we're just stuck with regardless.You know, just a couple of nudges, and a little bit of despin, and we could fix it so a year is exactly 360 days (a nice, readily devisable number) and a day is 86400 seconds (another nicely divisible number), without having to muck about with changing changing any time units or recalibrating chronographs. And we could keep engineers and physicists employed for decades figuring out how to effect the change in orbit without destroying all life on Earth. I'd suggest that some constant velocity swinging motors on the Moon should serve as the orbital tug, while extending large masses out on counterbalancing beanstalks will serve to reduce the Earth's rotational velocity.

Yes, it's yet another modest proposal from your friends at the National Council on Brilliantly Preposterous Ideas. Please, hold your applause until after my presentation on how to transmute raw sewage into precious stones using only WD-40, rubber bands, and surplus volumes of Congressional Quarterly.

Stranger

Gorsnak
09-15-2005, 06:20 PM
...but a chain is 22' [yards] (assuming you're talking about what I think you mean)
Oops. I said chain, I meant rod. Get those mixed up all the time. 4 rods to a chain, and for some reason I always think it's the other way 'round.

Gary "Wombat" Robson
09-16-2005, 09:48 AM
You know, just a couple of nudges, and a little bit of despin, and we could fix it so a year is exactly 360 days...When I was a child, I thought we should make all 12 months exactly 30 days, and then lump the leftover 5-1/4 (roughly) days at the end (or beginning) of each year into a huge international party. Change the week to ten days with a three day weekend (you now have 30% of your days off work instead of 28.28%) and we've got exactly three weeks per month, 36 per year. The year-end party isn't part of a week at all.

Today, the average person works 5 days per week, 50 days per year: 250 days. Under the new system, you'd work 7 days per week, 36 weeks per year: 252 days. The extra two days could be floating holidays. EVERY weekend is a three-day weekend.

Now that I look back on that idea, I like it even more than I did back then.

Chronos
09-16-2005, 02:15 PM
Aha! So there are ten chains in a furlong! I just *knew* that 10 had to show up as a conversion factor somewhere in the customary system! Prior to this, the best I could do was ten acres in a square furlong.

GorillaMan
09-16-2005, 03:14 PM
Aha! So there are ten chains in a furlong! I just *knew* that 10 had to show up as a conversion factor somewhere in the customary system!
Is there any number (within reason) that doesn't crop up? Plus, this measurement of 10 chains is purely a practical one, not something that came about through a desire for decimal simplicity. (And it's less convenient when it's measured as 40 rods!)

Gorsnak
09-16-2005, 04:11 PM
Is there any number (within reason) that doesn't crop up?
2 - cups in a pint, pints in a quart
3 - feet in a yard, miles in a league
4 - quarts in a gallon, rods in a yard, pecks in a bushel, etc, etc, etc
5
6 - feet in a fathom
7
8 - furlongs in a mile, fl. ounces in a cup
9
10 - chains in a furlong
11
12 - inches in a foot
13
14 - pounds in a stone
15
16 - ounces in a pound

There's a few higher ones, but they get pretty sparse. I can't think of any odd conversion factors higher than 3, unless we go with days of the week or square feet in a square yard, or other things that seem like cheating to me. Surely I'm missing some, though.

GorillaMan
09-16-2005, 05:31 PM
I'm determined to find a 'five' and a 'seven', at least! Gimme time...

GorillaMan
09-16-2005, 05:35 PM
One clove = seven pounds
One firkin = nine gallons

Two down, a handful to go...

Valgard
09-16-2005, 05:54 PM
Anyone remember the comedy routine set in ancient Rome with one merchant trying to convince another to switch to the decimal system instead of using I, V, L and so on?

"Enough! I shall never understand this if I live to be C!"

Balthisar
09-16-2005, 08:08 PM
A pint's a pound the world around. See, we English system people have metric (non-SI metric) system, too.

baloo
09-16-2005, 08:50 PM
Weight is a force and force should be expressed in Newtons.

The Kilogram is a unit of mass.

Oddly enough, pounds are correctly used in the "old system"; they are units of force. AND
But Jim Imperial who weighs 180 lbs on Earth does indeed weigh 30 lbs on the moon

The imperical weight does not vary. The use of pounds as a force is defined as the weight of a one-pound mass where the accelleration is 9.8 m per s per s.

Crafter_Man
09-17-2005, 12:14 AM
The Celsius scale is too course a measurement, anyway. There's too big a difference over one degree, let alone five.I would agree.

Unbeknownst to many, the Fahrenheit scale has almost twice the resolution as the Celsius scale for a given number of significant digits. Knowing this can come in handy in certain situations.

GorillaMan
09-17-2005, 01:48 AM
'Celsius is too coarse'? Assuming you're talking about everyday usage, I'd say that Farenheit is too fine. The weather can be predicted accurately to a specific degree on the Celsius scale, but only to 'high sixties' or similar in Farenheit.

Ximenean
09-17-2005, 05:59 AM
A pint's a pound the world around. See, we English system people have metric (non-SI metric) system, too.
Is that a US pint or a British pint?

Here we say, or used to say, "a pint of water, a pound and a quarter".

Chronos
09-17-2005, 12:33 PM
One firkin = nine gallonsThere's also nine hands in a yard.I can't think of any odd conversion factors higher than 3, unless we go with days of the week or square feet in a square yard, or other things that seem like cheating to me. Surely I'm missing some, though.How about 231 cubic inches in a gallon? Oh, and if we want to fill in that 5 gap, there's probably something in the Imperial liquid measures. Certainly, there are 5 American quarts in an Imperial gallon, but that seems cheating. Cups in a quart, perhaps?

And there are 11 fathoms in a chain, too. And should we count a baker's dozen?