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Brown
7th March 2003, 11:28 AM
From Randi's commentary
I wonder what Jefferson would have thought of the fact that in the 21st century, his country would still be fumbling with the awkward and ancient feet/pounds/Fahrenheit units that the rest of the world gave up long ago....? There is nothing inherently wrong with using feet and pounds as units of length and force. But in comparison to the English system, the metric system makes computation of quantities so much easier.

The unit of force in the metric system comparable to pounds in the English system is the newton (NOT the kilogram). One newton is the amount of force you need to accelerate one kilogram at one meter per second every second. (In the metric system, the kilogram is a unit of mass. The English unit of mass is, believe it or not, the slug.)

The unit of energy (or work) in the metric system is the joule. In the USA, almost nobody knows what a joule is, but everyone seems to be happy talking about calories. And yet one joule is easily computed as one newton times one meter. By contrast, one calorie is NOT one pound times one foot.

This interrelationship among units makes computations very easy to do in the meteric system. Using English units, you almost always have to apply conversion factors, because units tend not to be related. Conversion factors are not difficult to apply, but they are a pain in the @\$\$.

Jefferson did a lot of engineering calculation in his life. He probably would have loved the metric system. When you don't have to worry about conversion factors, the units "take care of themselves."

Even so, I do see the attraction of other systems of units. In particular, I find Fahrenheit units to be far more useful than Kelvins, for several reasons. First, the normal range of temperatures that a human may experience (very cold to very hot) are, in Celsius units, about -18 to 38, and in Kelvins, about 255 to 311. But the normal range of temperatures that a human may experience are, on the Farenheit scale, about 0 to 100. When looked at this way, the range provided by the Farenheit scale seems to be a good choice, and Kelvins seem terribly awkward.

And by the way, I don't believe most of the world uses the Kelvin scale for everyday measurements, even though the Kelvin is the unit of thermodyanamic temperature. (One can easily convert Kelvins to degrees Celsius by subtracting 273.)

Also, each Kelvin (degree Celsius) is equal to 1.8 degrees Farenheit. Many people are sensitive to temperature changes as small as one degree Farenheit. Until we start speaking in terms of half a degree, using the Farenheit scale makes some sense.

davefoc
7th March 2003, 01:19 PM
A little tilting at windmills here Brown?

I've done a little tilting myself on this one. I was working for a handheld computer company and I wanted to switch the new design over to metric screws since we were forced to use metric screws for part of it because of the need to mount a device that used metric screws. I thought this would be a slam dunk decision, 40% of our sales were overseas and it was time to leave the old behind, right?

Wrong. Manufacuturing didn't want any part of metric screws. They had their bins, they had their vendors, they were happy. Field service didn't want any part of metric, they had there spare screws in the foreign countries and they were happy. Marketing could have cared less. So we ended up dyeing the few metric screws blue so they didn't get confused with the non-metric and we stayed with non-metric.

There's another issue that you might have tilted at while you were at it. Tooling and metal parts in general in the US are almost always designed using mils (thousands of an inch). This is a nice convenient unit, albeit not compatible with the metric system.

Most other measurement in the US are based on fractions. This is an awkward approach compared to just using mils. How many times every day does somebody make a mistake while trying to add numbers like 7/32 and 3/8. Mils would be enormously easier and less error prone but I don't see any changes happening in that direction either.

Brown
7th March 2003, 02:11 PM
Originally posted by davefoc
A little tilting at windmills here Brown?Yes and no.

Folks who need to use multiple scientific units (e.g., chemists, physicists, engineers) learn the benefits of the SI system at once. Many of them prefer it. I haven't met too many of them who would fight to keep the old outdated units.

But there are a lot of folks (many of them rather, well, uninformed about science) who feel that the metric system is a tool of satan. This is no exaggeration. Some folks in the USA actually believe this.

Others don't like the idea of "the government" telling us that we have to use liters in our recipes, instead of cups and tablespoons. I have heard this argument made in all seriousness, too.

And there are also those who are upset about all of the infrastructure that would have to be replaced, such as mile markers. Of course, all sorts of government specifications or regulations or public records would have to be rewritten, at tremendous cost, they say.

Plus, you always run into the "If it ain't broke, don't fix it" crowd, which usually sits next to the "That's the way we've always done it" clique at the coffee shop.

So it's unlikely that the USA is ever going to move completely to the metric system soon. And that's too bad. Some people just prefer an inferior system because they're used to it, I guess.

One of my other points, by the way, was that Randi seemed to think that the Farenheit scale is outdated. I don't think it is.

K-W
7th March 2003, 02:32 PM
Which will come first. THe US switching to the metric system, or computers so taking over computation that it doesnt matter?

7th March 2003, 03:07 PM
There is nothing inherently wrong with using feet and pounds as units of length and force. But in comparison to the English system, the metric system makes computation of quantities so much easier.

I disagree. Any system that uses the same term for measuring weight and volume (ounce) is ludicrous.

Others don't like the idea of "the government" telling us that we have to use liters in our recipes, instead of cups and tablespoons. I have heard this argument made in all seriousness, too.

That's not just a U.S. thing. When Ireland converted over a few years back, the cry from the pubs was so loud that the legislation describing the changes had to specifically exempt pints (when used to measure ale).

Which will come first. THe US switching to the metric system, or computers so taking over computation that it doesnt matter?

I tried imagining what measuring computer storage space would be like if it were measured in English Scale units instead of using Metric prefixes, but my head started huring.

afree87
7th March 2003, 03:53 PM
I know full well about the dumb manufacturing supply thing, but even so, I've never had to pull out my calculator to change kilometers into meters. :) Of course, some of my teachers have asked me to give answers in Imperial units, but converting meters into furlongs and kilos into hogsheads is pretty easy, too.

There are some websites all about why the U.S. should stay with the Imperial system, and they're about as hilarious as the ones whining to "Take US out of the UN".

davefoc
7th March 2003, 06:58 PM
My wife just asked about how much of a cup five ounces of cheese was. This led, of course, to ladewig's issue with a volume measurement and a weight measurement having the same name.

This led to a discussion of density with my daughter and predictions of whether cheese would float or not. (My thought was that cheese would float seeing that it consists mostly of fat, in fact both mozzarella and parmesan sink). For those of you interested (undoubtedly a small number) five ounces (by weight)of parmesan cheese has a volume of four ounces. Finally we finished with a little topic on how to converst fluid ounces to pints and quarts. How can anybody argue for the metric system when fun like this is available with the English system?

And then there was the fun we didn't get into like that an ounce of water is only .96 fluid ounces or about how precious metals are measured in troy ounces which weigh somewhat more than a regular ounce.

Of course the important question is how many drams a board foot of parmesan weighs. That would be about 816.

Quixote
7th March 2003, 08:03 PM
For those of you interested (undoubtedly a small number) five ounces (by weight)of parmesan cheese has a volume of four ounces.

Is that grated or melted?

corplinx
7th March 2003, 10:48 PM
Let me be crusty here for a minute. I love and loathe imperial units. Beer by the pint, milk by the gallon, and tea by the cup. I think going gung ho and forcing everyone to give up imperial measures that have a good natural utility is wrong.

On the scientific end of milk production, you put so many milliliters in a jug. The consumer buys the jug as a gallon.

Some measures just seem to "fit". Any remember 1 gallon glass bottles of soda? Somehow the 2 liter just "fits".

However, when I read about scientists whose creations fail because of some metric/imperial mixup, I nearly pop a vein. Silly scientists, imperial units are for consumers!

The metric system was a great idea for standard measures. However in the process of designing them, someone forgot to ask "how useful will this be for my mom?".

I think the lesson is that utility can be just as important as technical merit.

arcticpenguin
9th March 2003, 09:58 AM
Originally posted by Brown
There is nothing inherently wrong with using feet and pounds as units of length and force. But in comparison to the English system, the metric system makes computation of quantities so much easier.

Paraphrase "The English system of units makes it difficult to compute quantities"

If you're going to contradict yourself in your first paragraph, you're not leaving much work for those of us who would refute you.

9th March 2003, 11:14 AM
Beer by the pint, milk by the gallon, and tea by the cup. I think going gung ho and forcing everyone to give up imperial measures that have a good natural utility is wrong.

On the scientific end of milk production, you put so many milliliters in a jug. The consumer buys the jug as a gallon.

Some measures just seem to "fit". Any remember 1 gallon glass bottles of soda? Somehow the 2 liter just "fits".

There are probably a fair number of good examples you could have chosen, but milk by the gallon is hardly one of them. A four-liter container holds only 6% more than a U.S. gallon (not to be confused with an imperial gallon). One can not seriously maintain that 128 fl. oz. container of milk has more natural utility than 135 fl. oz. container of milk.

Brown
9th March 2003, 05:52 PM
Originally posted by arcticpenguin
Paraphrase "The English system of units makes it difficult to compute quantities"No, I don't wanna.Originally posted by arcticpenguin
If you're going to contradict yourself in your first paragraph, you're not leaving much work for those of us who would refute you. My first paragraph is self-consistent and not self-contradictory. Perhaps you'd care to point out a perceived contradiction.

thatguywhojuggles
9th March 2003, 11:30 PM
This may not be the right place to post this rant, but I will anyway.

The rest of the world needs to switch to PAL video format!!!

iain
10th March 2003, 12:14 AM
Originally posted by thatguywhojuggles
This may not be the right place to post this rant, but I will anyway.

The rest of the world needs to switch to PAL video format!!!
Most of the world is on PAL. The problem (as I found when I moved to Holland) is that there are different sorts of PAL.

The Netherlands supports PAL-G and PAL-B (the most common types). The UK and Ireland run on PAL-I.

From experience I can say that if you have a PAL-I television in a PAL-B/G country you can choose between sound or picture but you can't have both at the same time.

Luckily, video cassettes are just "PAL" so you can play the same casette on a Dutch VCR or an English VCR.

iain
10th March 2003, 12:24 AM
Growing up in England when I did meant doing some things in metric and others in imperial (note : the confusion is increased slightly more because some English Imperial measures (e.g. gallon) are different from their US equivalents).

For example, I grew up working out the height of people in feet and inches but the height of objects in metres and centimetres. I understood the weight of people in stones and pounds but of most objects in kilograms and grams.

The UK is slowly moving to the metric system, not before time. Temperature is now in Celcius, petrol in litres, fruit and vegetables weighed in kilos and measurements of length more commonly in metres than yards. However, not everything changes. I can't see a change from miles to kilometres any time soon, for example.

Just as in the US, there are people who see the move to metric as the end of civilisation and/or some evil European plot. But just as with currency decimalisation (remember in the UK until 1971 there were 12 pence to the shilling and 20 shillings to the pound) people kick up a lot of fuss at the time but get used to it pretty quickly.

Across Europe much the same thing has been seen with the Euro. Predictions of disaster have failed to come true and the introduction of Euro notes and coins has gone about as smoothly as it possibly could have done.

10th March 2003, 08:53 PM
But just as with currency decimalisation (remember in the UK until 1971 there were 12 pence to the shilling and 20 shillings to the pound) people kick up a lot of fuss at the time but get used to it pretty quickly.

You've never been to rural Mississippi. They're still pretty bothered about losing the War Between the States. Metric could never be adopted in the U.S.

davefoc
10th March 2003, 10:11 PM
I thought it might be interesting to start a list of areas that have switched to metric system in the US. Some of these I'm unsure of so feel free to correct me.

1. Soda pop is sold in two liter bottles
2. Wine is sold in 750 ml bottles
3. Medicine is sold in milligrams, grams, cc's, etc
4. The military measures distances in kilometers
5. Many car manufacturers have switched to metric screws (I think)
6. Most big time track events have metrically based events (100 meter dash, etc)
7. Most scientific work is done and published with metric measurements.
8. American cars have kilometer per hour marks on their speedometers.

arcticpenguin
11th March 2003, 06:18 AM

You've never been to rural Mississippi. They're still pretty bothered about losing the War Between the States. Metric could never be adopted in the U.S.
Maybe you could convince them that dropping the English units would be a good way to get back at those d_mn yankees.

WanderingKnight
13th March 2003, 08:08 AM
Originally posted by davefoc
I thought it might be interesting to start a list of areas that have switched to metric system in the US. Some of these I'm unsure of so feel free to correct me.

1. Soda pop is sold in two liter bottles
2. Wine is sold in 750 ml bottles
3. Medicine is sold in milligrams, grams, cc's, etc
4. The military measures distances in kilometers
5. Many car manufacturers have switched to metric screws (I think)
6. Most big time track events have metrically based events (100 meter dash, etc)
7. Most scientific work is done and published with metric measurements.
8. American cars have kilometer per hour marks on their speedometers.

Are measurements of computer memory considered as being part of the metric system? IE kB, MB, GB?

Mr. X
13th March 2003, 08:43 AM
Originally posted by thatguywhojuggles
This may not be the right place to post this rant, but I will anyway.

The rest of the world needs to switch to PAL video format!!!

Actually the inventors of PAL forgot the HUE (phase) control and had to stay with the PAL system. The 50 cycle (hertz) flicker had them spellbound....

Mr. X

Thumbo
13th March 2003, 09:33 AM
Originally posted by WanderingKnight

Are measurements of computer memory considered as being part of the metric system? IE kB, MB, GB?

No, because they are are not units, just dimensionless numbers.

Those who make the standards say that computer memory shouldn't be counted in MB or GB anyway, but in MiB (mebibytes) and GiB (gibibytes).

Honest - those are the standard prefixes now: http://physics.nist.gov/cuu/Units/binary.html

They don't seem to be catching on, especially amonst ventriloquists. :)

Occasional Chemist
13th March 2003, 09:42 AM
Originally posted by Brown
(In the metric system, the kilogram is a unit of mass. The English unit of mass is, believe it or not, the slug.)

To add to the confusion, the commonly used unit of mass in the English system is the lbm, or pound-mass, rather than the slug.

The unit of energy (or work) in the metric system is the joule. In the USA, almost nobody knows what a joule is, but everyone seems to be happy talking about calories. And yet one joule is easily computed as one newton times one meter. By contrast, one calorie is NOT one pound times one foot.

The foot-pound is the English unit of energy.

The calorie is the amount of energy required to heat a gram of water a degree Celsius. This is something of a handy unit for calorimetry.

edited to add: And that calorie everyone's so happily talking about isn't actually a calorie, it's a kilocalorie.

Using English units, you almost always have to apply conversion factors, because units tend not to be related. Conversion factors are not difficult to apply, but they are a pain in the @\$\$.

It's not that you don't need conversion factors for metric units. It's more that there's a unified set of base units and a unified set of conversion factors rather than the chaos that is the English system.

Occasional Chemist
13th March 2003, 09:50 AM
Originally posted by davefoc
I thought it might be interesting to start a list of areas that have switched to metric system in the US.

Power expressed in watts?

13th March 2003, 09:54 AM
Originally posted by Occasional Chemist

Power expressed in watts?

Grams of cocaine?

davefoc
13th March 2003, 11:19 AM
Well I thought I'd update the list every now & then so this is the first update.

Davefoc
1. Soda pop is sold in two liter bottles
2. Wine is sold in 750 ml bottles
3. Medicine is sold in milligrams, grams, cc's, etc
4. The military measures distances in kilometers
5. Many car manufacturers have switched to metric screws (I think)
6. Most big time track events have metrically based events (100 meter dash, etc)
7. Most scientific work is done and published with metric measurements.
8. American cars have kilometer per hour marks on their speedometers.

Occasional Chemist
9. Power expressed in watts (and all other electrical measurements like amps and volts)

sundog
10. cocaine measured in grams

Thanks to various people who contributed interesting little tidbits. I had no idea that somebody was trying to eliminate confusion on issue of computer memory size. e.g. 1K of RAM =1024.

Chris Haynes
14th March 2003, 02:07 PM
Originally posted by Occasional Chemist

To add to the confusion, the commonly used unit of mass in the English system is the lbm, or pound-mass, rather than the slug.

...It's not that you don't need conversion factors for metric units. It's more that there's a unified set of base units and a unified set of conversion factors rather than the chaos that is the English system.

What mass unit is used may also be dependent on WHO is using them...

In my former life as a structural dynamics engineer we had to be very careful about units. In my group the lbm was not looked kindly upon since it required the use of some unitless "Gravity constant". What we used since we were dealing with weight and force in "pounds" and dimensions of "inches" were "slinches" (or snails... but NOT slugs).

To keep correct units the Finite Element program/models (along with the motion analysis program, Language for Structural Dynamics: LSD) were set to devide all force (and weight) values by 386.4 in/sec^2 .

Now this is what drove me nuts (and out of Forum lurkdom)... Since I had spent most of my youth NOT in the USA I am quite comfortable using SI units. Over 20 years ago during my first year of work I was sent with a lead engineer (who was German) to do some temporary analysis work for an off-shore oil rig that was under-construction in the UK (running simulations on our computers here in the US).

That particular UK company was NOT using Newtons, a perfectly adequate SI unit for force. NOooo... they had decided to invent and use "kilogram-force" units.

PS: an aside --- my mother-in-law tells us that her first husband, an engineer who moved from the Netherlands to Canada, would work by first converting all the English units (still being used in Canada) to SI, do the work and then convert the results back to English.

17th March 2003, 05:15 AM
11. Radio (but not television): hertz is metric and when shortwave is not measured in hertz it is measured in meters.

LW
17th March 2003, 07:46 AM
Originally posted by Brown
First, the normal range of temperatures that a human may experience (very cold to very hot) are, in Celsius units, about -18 to 38, and in Kelvins, about 255 to 311. But the normal range of temperatures that a human may experience are, on the Farenheit scale, about 0 to 100.
I'm not that certain about the normal temperature ranges that are experienced. During the last few months I've been in temperatures varying from -25 to +110 Celcius (the latter in sauna, a little too hot for my tastes). I'd say that the temperature scale is necessarily arbitrary and it is more or less a matter of preference. The one nice thing about Celcius scale is that it makes checking whether roads are likely to have ice very quick, as one has to check only the sign of the temperature.

Zep
17th March 2003, 09:08 PM
Said this before somewhere, and can't find the reference...

Australia went metric completely in the mid-70's (was it the drugs? ;) ) over a few years. The earth didn't stop rotating, the sun rose again every day. A can of beer that was previously 10oz became 330ml, but stayed the same can of beer. A metric cup of milk at 250ml was within a bee's whisker or so of 8ozs, but mum's cakes turned out just the same. Somehow the cities and towns didn't get further away or closer when the distances went from miles to kilometres, and the amount of petrol used to get there was pretty much the same in litres or gallons.

In short, we ditched a system of measurements created in the medieval ages with a newer one of much greater practicality and ease of use, and didn't suffer as a result. Perhaps we have evolved further here? :D

Zep

Chris Haynes
17th March 2003, 09:32 PM
Originally posted by Zep
... A metric cup of milk at 250ml was within a bee's whisker or so of 8ozs, but mum's cakes turned out just the same. ..
Zep

I have waited a long time for the US to change... but here we are the repository of old ways. The folks in New Orleans speak a French that is old... and those of us of Scandinavian descent still make cookies that are not often seen on Norwegian nor Swedish tables at Christmas (got this from a conversation with Swedish Cadets from a training vessel "Alvsnabben" (? sp) when we asked them about Fatigmann and Sandbuckles) ---

I would really like to see us turn from the old (How many feet to a mile???), and get with the rest of the world.

Of course, I still remember recipes for Rice Crispy Bars from the box in Venezuela that had one of the measure in "tasa" ( cup ).

HCN (I still buy wine in 750 ml bottles)

Zep
19th March 2003, 05:41 PM
Of course, I still remember recipes for Rice Crispy Bars from the box in Venezuela that had one of the measure in "tasa" ( cup ).

Yeah! I asked my mum for one of her recipes for meatballs in tomatos. The ingredients are things like: "Make as many meatballs as you want to eat, use enough salt to taste right", etc. I don't think anyone could metrify that, nor do we want to!

Zep

UnrepentantSinner
19th March 2003, 07:43 PM
Will no one mourn the passing of drams, gills, slugs, rods, fathoms and furlongs?

I shall. ;)

Zep, when I was in Germany we used to get 330ml cokes. They seemed a bit smaller than the 12 oz. ones we got on base. When I checked, sure enough, there was a 25ml difference. I wouldn't mind getting screwed out of 5m (a 350ml can would be fine by me) but over the course of a year, assuming I payed the same \$.60 25ml would add up.

Ove
20th March 2003, 10:56 PM
I'm not that certain about the normal temperature ranges that are experienced. During the last few months I've been in temperatures varying from -25 to +110 Celcius (the latter in sauna, a little too hot for my tastes). I'd say that the temperature scale is necessarily arbitrary and it is more or less a matter of preference. The one nice thing about Celcius scale is that it makes checking whether roads are likely to have ice very quick, as one has to check only the sign of the temperature.

I gotta agree with you there. I've never heard the explanation Brown gave (that 0-100 is what a man would encounter). It sounds a bit far fetched to me.

The celicus scale OTOH is based on the assumption that water freeses at 0° and boils at 100°. Childlishy simple.

The Kelvin scale is similar only it starts at the "absolute zero" -273° C.

One place where the decimal system has NOT been accepted is in navigation/surveying. a circle is still 360° and the subdivisions are still minutes and seconds.

There have been made both compasses and surveying instruments based on a 400° circle which makes calculations much much easier. PArt of my education was surveying and we used the old 360° instruments. Sheer hell. We had to map a fiels and measure the angles-elevations etc. using 360° theodolites. it was horrible.

When i later used it in my work i made the most horrible mistake. We was out to mark the ground for a row of houses my compagnywas going to build and the first thing was off course to line up the fronts of the houses using a theodolite. They was supposed to be at a right angle to the main road and i plottede them nicely at 90°. Yes you've guessed it, i was using a new japaneese theodolite which used a 400° circle. :(

Luckily somebody discovered before they started digging and an extra weekend of work saved the situation but boy did my ears glow. http://www.handykult.de/plaudersmilies.de/rotwerd.gif

rustypouch
21st March 2003, 12:16 PM
If you don't like the 360 degree circle, you could always work with mils. 6400 mils to the circle. Think about it.

NoDeity
21st March 2003, 12:45 PM
Originally posted by LW
I've been in temperatures varying from -25 to +110 Celcius (the latter in sauna, a little too hot for my tastes).Are you sure that the temperature was 10 degrees above the boiling point of water? That would be a little hot for my tastes, too -- unless perhaps I was a nice ear of corn being steamed for dinner.

The one nice thing about Celcius scale is that it makes checking whether roads are likely to have ice very quick, as one has to check only the sign of the temperature. I agree with you there. I find it very convenient calling the freezing point of water "zero". It won't matter much to those who live in warmer climates, I suppose.

NoDeity
21st March 2003, 01:09 PM
Originally posted by Zep
Australia went metric completely in the mid-70's
Canada, too. For those of us who were already in high school (or older) when the switch was made, it didn't "take" as completely as it did for the younger folks but it's not so bad. I didn't make much of an effort to convert -- I just went with the flow.

I think in both metric and imperial. I think of speed in km/h but I think of distance in miles. I think of temperature in degrees centigrade but I think of human height in feet and inches and human weight in pounds (and, for babies, pounds and ounces).

I measure baking ingredients in cups, tablespoons and teaspoons (although the metric would certainly be simpler to remember) but when I think of buying gasoline, engine oil or containers of beverages, I think of litres (ml for smaller amounts, of course).

You might think it's confusing but I don't find it so. It works for me. When it happened, I welcomed the change. However, I might have been brainwashed into it by television scifi: I was a fan of Mr. Spock and metric is clearly a much more logical system so, to me at the time, that meant it had to be better.

Zep
23rd March 2003, 04:00 AM
No, NoDeity, I don't find it confusing at all. :)

I started my schooling with pounds, shillings and pence, rods, furlongs, feet, yards, miles, stones and hundredweights, etc. Don't know how many hours I spent on detention because my maths homework was wrong! So oh, how I welcomed decimal currency, and shortly afterwards, metrification! Somehow my afternoons became longer and happier!

Yep, we still use the expression "a cup" of flour or sugar or whatever in recipes - it's just 250ml instead of 8oz. Similar for teaspoons (5ml) and tablespoons (15ml). Milk is still in big and small cartons, now 1 litre and 600ml respectively instead of a pint and a quart. A "pound of bacon" is half a kilo of same, and just as nice when cooked properly.

And we still use expressions like "Give him an inch and he'll take a mile", and "An ounce or prevention is worth a pound of cure", although my post-metric daughter looks at me sorta funny when I say that to her... :)

Anyway, seems us Ozzies and Canadians somehow muddled through being metrified without too much hassle. So I wonder what's holding up our Yankee cousins?? :D

Zep

Ove
24th March 2003, 10:14 PM
Anyway, seems us Ozzies and Canadians somehow muddled through being metrified without too much hassle. So I wonder what's holding up our Yankee cousins??

The one thing that is most difficult to kill: OLD HABIT..........:D

LW
26th March 2003, 05:53 AM
Originally posted by NoDeity
Are you sure that the temperature was 10 degrees above the boiling point of water? That would be a little hot for my tastes, too -- unless perhaps I was a nice ear of corn being steamed for dinner.
Well, measuring the temperature of a sauna is a quite difficult thing to do since it varies as a function of height (the higher up you are in a sauna, the hotter it is) and sauna thermometers are not particularly accurate. In that particular case the thermometer read 115 degrees Centigrade, and it was located roughly 10 cm over my head.

The one thing that makes it possible to stay in hot sauna is that air and wood are very poor conductors of heat. The steam that results from throwing water to stones dissipates quickly and burns only for few seconds. That is, unless some idiot (usually drunken) decides to show though he is (for some reason I've never witnessed a woman to act like this) and throws lots and lots of water at one time. In those cases it is possible to get first degree burns, usually on shoulders and ears.

belinda
27th March 2003, 03:04 PM
Originally posted by NoDeity

I think in both metric and imperial. I think of speed in km/h but I think of distance in miles. I think of temperature in degrees centigrade but I think of human height in feet and inches and human weight in pounds (and, for babies, pounds and ounces).

Even though I went to school after the metric system had been brought in, I grew up thinking of things like height and weight in in the Imperial system, simply because that is what my parents and others used. When my own child was born, though it was metric all the way and a heavy 4.145kg he was too. Now I would have no idea how to convert human measurements from metric to Imperial. Good for my ego too, I never know if I need to be jealous of some girl who is 110lbs!

Originally posted by Brown
But there are a lot of folks (many of them rather, well, uninformed about science) who feel that the metric system is a tool of satan.

I guess it's not the lucky country after all, Satan has succesfully deployed the horrific tool of metrics here :D

william1165
28th March 2003, 08:23 AM
11. Radio (but not television): hertz is metric and when shortwave is not measured in hertz it is measured in meters.

Hertz is not metric, unless "seconds" is considered metric. Hertz is a frequency, not a wavelength.

IPFreeley
28th March 2003, 09:14 AM
I think the primary reason most people are hesitant about using the Metric system is because it's hard to imagine quantities. If I told someone to pour me 300 mils of soda pop, or it's 300km to our destination, most people wouldnt know how much to pour or how much farther to drive and I'm the same way in most cases. Of course, knowing how to estimate means having to use the system, a catch-22.

I think almost all cars now are fully metric but what about the wheels? Rims are still measured in inches. There was the TRX wheel in the 1980s which was metric, but fell out of use after a few years.

I have a 1979 Ford that has a metric engine and transmission, and the rest of the car is standard sizes so I need to have two sets of tools to work on it depending.

NoDeity
28th March 2003, 11:09 AM
You could be right. It becomes easy to imagine quantities, though. I have a few empty containers sitting on my desk, including a 355 ml pop can and a 500 ml water bottle. We have a 4 litre jug of milk in the fridge. When everyday consumer goods are measured in metric, people get the idea pretty quickly.

It used to be about 45 miles to the next town. Now it's about 70 km. When familiar distances are expressed in km on highway signs, people get the idea.

And so on.

(I can imagine 70 km about as easily as I can imagine 45 miles but I still tend to think miles first. I guess I'm a fossil.)

davefoc
28th March 2003, 11:56 PM
second and possibly last update

Davefoc
1. Soda pop is sold in two liter bottles
2. Wine is sold in 750 ml bottles
3. Medicine is sold in milligrams, grams, cc's, etc
4. The military measures distances in kilometers
5. Many car manufacturers have switched to metric screws (I think)
6. Most big time track events have metrically based events (100 meter dash, etc)
7. Most scientific work is done and published with metric measurements.
8. American cars have kilometer per hour marks on their speedometers.

Occasional Chemist
9. Power expressed in watts (and all other electrical measurements like amps and volts)

sundog
10. Cocaine measured in grams (also marijuana)

11. Electromagnetic wavelengths measured in meters, millimeters and nanometers (and have been as long as I can remember).

12. Time based on seconds which are part of the metric system. So frequency measured in Hertz is part of metric system also.

IPFreeley
13. Tires are sized at least paritially in millimeters.

arcticpenguin
30th March 2003, 01:51 PM
How are eggs sold in metric countries? By the dozen, or in packs of 10?

NoDeity
30th March 2003, 05:07 PM
Here in Canada, eggs are most often sold by the dozen. Some stores also offer packages of 6 or 18.

There's really no point in changing something like that. :)

Chris Haynes
30th March 2003, 09:54 PM
Originally posted by davefoc
12. Time based on seconds which are part of the metric system. So frequency measured in Hertz is part of metric system also.
..

I am more willing to believe that time is "SI" than metric. In other words... something that is part of the International System... but not based on the meter. There are still 60 seconds to a minute, 60 minutes to an hour and 24 hours to the day, none of them are decimal numbers. I have not looked at the historical reasons for this... but I'm willing to bet it dates back to the same (Babylonian??) reasoning that there are 360 degrees in a circle.

I see no particular reason why we could not have 10 (or 100) hours in a day... each being divided by 100 minutes, which are then divided by 100 seconds.

I could see it make navigation a bit more logical.

Then all we would need to do is figure out how to divide the naturally occuring cycle of 365 1/4 (+/- whatever seconds) it takes for our planet to revolve around the Earth into something easier than what we have now -- a bit over 52 weeks (which are 7 days long), bunched into 12 months, which have anywhere between 28 to 31 days (which kind of corresponded to the orbit of the moon).

This would require going through LOTS of inertia for change. It took several centuries most of the world to change between the Gregorian to the Julian calendar (from the 1700's to the 20th century for many countries). Actually some folks still rely on the Gregorian calendar to practice certain holidays (which is why some of them are celebrating Easter and Christmas at different times).

I did a Google search on "Julian Gregorian calendar history" and found all sorts of interesting reading. I did not realize are MANY calendars were used!

Here is one:
http://scienceworld.wolfram.com/astronomy/Calendar.html
and another:
http://astro.nmsu.edu/~lhuber/leaphist.html

I think I just commited thread drift.

davefoc
31st March 2003, 12:28 AM
Hydrogen,
MKS, SI and metric seem to be approximately synonomous. MKS (meters, kilograms, seconds) seems to have been replaced by SI (system International). Whatever you call it, these systems use the second as the basis of time so it seems that that Americans use of seconds was rightfully another example of the use of the metric system in the US.

See this link for info on the SI system.
http://whatis.techtarget.com/definition/0,,sid9_gci523539,00.html

Hertz is also an officially recognized unit in the metric system, so maybe it deserved its own line.

As to your 10 hours day suggestion, I think the French actually tried to get that going around the time of the introduction of the metric system, but it didn't catch on.

Penultimately, I agree about that calendar stuff, it is interesting. I'm not quite sure I followed your Julian and Gregorian comments. The Julian came first and the Gregorian is what we follow today. Also I'm not so sure about your comment about different Easter and Christmas dates. I believe the Greek Orthodox church uses Gregorian calendar also. The reason for the different dates is complicated and I have forgotten it if I ever knew it, but if the Greek Orthodox church was still using the Juslian calendar the dates of their holidays would be off by about a day for every 131 years since they started calculating and I don't think this is happening.

Lastly, as to the thread drifting, my view is that that thread drifting is only a crime in the first page (except of course when I do it;) ), by the second page it's only a misdemeanor and by the end of the second page on a thread that is losing interest anyway it might even be a good thing.

Houngan
1st April 2003, 05:02 PM
The inherent superiority in the metric system lies not in the units, but in the simple fact that, where possible, all measurements are in a decimal format. If we wanted to adopt the foot as an SI unit, and then defined all other measurements as an order of magnitude above and below a foot, it would be just as good.

I get into this discussion with people fairly often, and here's my favorite argument:

"You give me a freshman in high school and a Ph.D. of Mathematics, and that freshman can tell me how many millimeters in 2.43 kilometers a hell of a lot faster than the Ph.D. can tell me the inches in 2.43 miles. THAT'S why the metric system is better."

H.

UnrepentantSinner
1st April 2003, 10:02 PM
http://www.ecben.net/calendar.shtml
The coolest date/time website I've ever seen.

Walter Wayne
2nd April 2003, 12:28 AM
Originally posted by Hydrogen Cyanide
... Actually some folks still rely on the Gregorian calendar to practice certain holidays (which is why some of them are celebrating Easter and Christmas at different times).
. Orthodox christians and jews often rely on a lunar calender, in which the months equate more precisely with the moon. This has nothing to do with the Julian or Gregorian calender. Lunar calenders have 12 or 13 months in a year, varying from year to year.

Easter is still somewhat lunar. I believe it occurs on the first Sunday after the first Full moon after the Spring Equinox, but someone may be able to correct me on that.

Walt

bjornart
2nd April 2003, 03:16 AM
Originally posted by Hydrogen Cyanide

I am more willing to believe that time is "SI" than metric. In other words... something that is part of the International System... but not based on the meter.

It's actually the other way round. Although the meter is still considered one of the seven base units the definition is now based on the second and the properties of light in vacuum, rather than on the meter rod in Paris.
The definition is: 'The meter is the length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second.'

SI definitions (http://physics.nist.gov/cuu/Units/current.html)

Soapy Sam
2nd April 2003, 02:28 PM
Houngan puts his finger right on the strength and the dreadful weakness of any decimal system:- It's so easy to use. You just move the decimal point. You don't have to think. And we don't.

And if you move it the wrong way, you hit Mars at 10m/sec. Or was it 100m/sec? Or .001km/sec, or 100km/sec...?

Noone would ever have asked how many inches there are in 2.43 miles. (2.43 x 63360 as I recall), because he would have measured it as 2miles 756 yards, 2 feet, 5 inches, which would be precise enough for most operations. Knowing how many millimetres there are in 2.43 km tells you precisely nothing, you have simply substituted one unit for another.

Though for simplicity of calculation- what's the cost of a dozen eggs at 3d an egg?
3 Shillings.

You didn't have to be a genius, but yes, you did have to think. I'm not convinced that was a bad thing.

Zep
2nd April 2003, 03:24 PM
Soapy Sam, you make a good point, but I think it is to do with the appreciation of scale rather than the units of measurement. While the metric system does not relieve the user of the duty to take care with the scale of numbers, it does tend to help tremendously in the operation of the arithmetic.

Your saying that the number of millimetres in 2.43 km gives you no new information is *precisely* the point of metrification. Either measurement is correct and they are directly interchangeable. Further, it took no complex arithmetic to obtain the conversion. An additional advantage is that precision can be maintained just as easily: 2.7345287 km is as accurate as 2734.5287 metres or even 2734528.7 millimetres!

Here's an example where small-to-large units conversion plays a part: A geologist notes that a certain sediment of rock has on average 27 layers per inch and it is 17'6'' thick. So how many layers total? The answer involves (probably) conversions of units involving more complex arithmetic (factors of 12). By comparison, if the measurement was 17 layers for cm, and the sediment 13 metres thick then no *complex* units conversions are required - it may even be possible to do this as a piece of simple mental arithmetic!

However I do agree that the movement of the decimal point IS important. Hitting Mars at 1m/S is a lot different to 1km/S...! :D

Zep

a_unique_person
3rd April 2003, 08:08 PM
Originally posted by Ove

The one thing that is most difficult to kill: OLD HABIT..........:D

you don't have to kill us, we'll die one day.

a_unique_person
3rd April 2003, 08:13 PM
Originally posted by IPFreeley
I think the primary reason most people are hesitant about using the Metric system is because it's hard to imagine quantities. If I told someone to pour me 300 mils of soda pop, or it's 300km to our destination, most people wouldnt know how much to pour or how much farther to drive and I'm the same way in most cases. Of course, knowing how to estimate means having to use the system, a catch-22.

I think almost all cars now are fully metric but what about the wheels? Rims are still measured in inches. There was the TRX wheel in the 1980s which was metric, but fell out of use after a few years.

I have a 1979 Ford that has a metric engine and transmission, and the rest of the car is standard sizes so I need to have two sets of tools to work on it depending.

All of our tools still come in metric and imperial, 30 years later. I think the sooner we get rid of people making things in imperial sizes, the sooner the problelm will disappear.

As for the change over, it's pretty easy with some good will and commonsense. You want to keep calling your pint a pint? No problem.

Babies are still pounds.

But if people don't want to change, it will just be a nightmare. If they work with the change, it is so easy you wonder why it took so long.

Perhaps the US should consider dropping the dollar and going back to the pound?

rwguinn
24th April 2003, 07:28 PM
In many instances, the metric system is good-converting from "milli" to "kilo" is simple, for example.
I must take issue, however with your Force bit. Weight is a force. Every item measured for weight is in kilograms, grams, whatever. Now, you have to convert. at this point, you need to remember 9.808m/sec^2- the acceleration due to gravity. This is not a whole lot easier to remember than 32.2 ft/sec^2. But you get it converted.
Now, you have Newtons.
Let's find pressure-N/m^2, right? Nope, we're going to call it Pascals (Pa) Something else to remember.
Let's consider another engineering term- torque. We like working in a right-hand coordinate system. We also have conventions for matrix algebra, where, as we all know, [a]X[b] is NOT equal to [b]X[a]. Torque is [x]X{f}, which has the units (length-force). The metric system insists on N-m, which by implication is {f}X[x], so you either have to transpose the arrays, or remember that is is backwards.
I don't mind this, if you want to be that way. I use both, depending on how the data arrives. The real problems come in converting-so pick your favorite units, and stic with them-then convert. I personally work generally in inches (g=386.1 in/sec^2) pressure/stress is in lbf/in^2, and so on. Just stick with the system you're familiar with, and leave the conversion to the religico's.....:D

Roger

william1165
28th April 2003, 01:21 PM
Just look at how we designate tire sizes...

P255/65R15.

255 is the width in MILLIMETERS.

15 is the diameter of the rim in INCHES.

Now, are we metric or not?

allanb
6th May 2003, 10:47 AM
Originally posted by Zep
No, NoDeity, I don't find it confusing at all. :)

Anyway, seems us Ozzies and Canadians somehow muddled through being metrified without too much hassle. So I wonder what's holding up our Yankee cousins?? :D

Zep

I think it's because so many American homes are built using vertical studs with either 18" or 24" centre-to-centre spacing. If the US switches to the metric system, millions of houses will fall down.

davefoc
6th May 2003, 12:38 PM
Another update, to the list since the thread continues to draw the odd comment or two.

American use of the metric system

Davefoc
1. Soda pop is sold in two liter bottles
2. Wine is sold in 750 ml bottles
3. Medicine is sold in milligrams, grams, cc's, etc
4. The military measures distances in kilometers
5. Many car manufacturers have switched to metric screws (I think)
6. Most big time track events have metrically based events (100 meter dash, etc)
7. Most scientific work is done and published with metric measurements.
8. American cars have kilometer per hour marks on their speedometers.

Occasional Chemist
9. Power expressed in watts (and all other electrical measurements like amps and volts)

sundog
10. Cocaine measured in grams (also marijuana)

11. Electromagnetic wavelengths measured in meters, millimeters and nanometers (and have been as long as I can remember).

12. Time based on seconds which are part of the metric system. So frequency measured in Hertz is part of metric system also.

IPFreeley
13. Tires are sized at least paritially in millimeters.

davefoc
14. Engine displacement is routinely listed in liters. The old use of cubic inches seems to be dieing out.

15. American medical practice uses metric almost exclusively.

Allanb:
American wood frame houses are generally built with studs on 16 inch centers, and 24 inches in some cases. I don't know how far back the 16 inches goes but I maintain a 75 year old building that was built on 16 inch centers and it probably goes back well before that.

What is the spacing for studs in a European wood frame house?

allanb
6th May 2003, 11:24 PM
Originally posted by davefoc
American wood frame houses are generally built with studs on 16 inch centers, and 24 inches in some cases. I don't know how far back the 16 inches goes but I maintain a 75 year old building that was built on 16 inch centers and it probably goes back well before that.

What is the spacing for studs in a European wood frame house?

My mistake, 18 instead of 16.

Slightly more seriously, even if the US goes metric, I'm sure it will be a long time before "two-by-four" disappears from the language.

I've no idea about wood frame construction in Europe, but it's much less common than in the US. If any international standards exist I don't know what they are.

NoDeity
6th May 2003, 11:35 PM
Canada's been metric since the '70s but we still make and buy 2 x 4s. I'll have to ask my contractor friend about studs but I hear of 16" centres and 24" centres; I've never heard anyone talk about metric stud spacing.

When you buy flooring, though, it's by the square metre and the thickness of your window glass is measured in millimetres.

We still say "missed it by a mile", "ninety-nine pound weakling", "an ounce of prevention...", etc.

bjornart
7th May 2003, 01:47 AM
Norway converted to metric in 1875. We still have 'two-inch-four' beams, but we buy them in meter lengths. A 'four-inch' is a four inch long nail. You need tools for both metric and imperial bolts and nuts. Most builder's rulers have both centimeters and inches, and the folding kind is called either an 'inch-rod' or a 'meter-rod' (people might call it an 'inch-rod' even if it only has centimeter markings).
Some things have just been too inconvenient to change, but I haven't really thought about it until today. Part of the reason might be because it's very rare you have to do calculations with the relic units, or maybe it's just that I never build things.

Soapy Sam
7th May 2003, 03:37 PM
I recently used a metric tape to measure some tanks.(Volume tanks, not the military kind). I found myself repeatedly making errors of one kind:- Reading 2m 9.5cm, I would write 2950 instead of 2095. At the end of the operation, I did a mental
" divide by 100 and multiply by 4" to get a rough figure in inches, which immediately told me I had made a mistake. I went back and did it all again with an inch tape. The figures came out to 1/8th inch accuracy. I realise this is a matter of habit and practise, but I still find quirky units and fractions innately easier to use mentally than decimals, precisely BECAUSE the arithmetic is harder. It forces me to think.
As for unit pricing, nothing will convince me that a decimal system beats a duodecimal one, simply because of the ability to subdivide twelve four ways as opposed to the two factors of ten. It's just twice as flexible.
In pre decimal currency in Britain, one third of a pound was 6 shillings and 8 pence-("six and eight") 80 pence from the original 240. It was so simple, four year old kids could do it , and did! I clearly recall our first class in school, aged five or less, playing shops with cardboard coins and damn right we gave the correct change! Nearly every kid in class could count money. I doubt any of us could have told you what ten percent of a hundred was. Money wasn't mathematical. It was...Money! The best incentive to learn mental arithmetic ever invented.

Earthborn
9th May 2003, 07:25 PM
How are eggs sold in metric countries? By the dozen, or in packs of 10?In the Netherlands, which has been metric for a long time, becuase we were once occupied by Napolean's France, eggs are usually sold in packs of 10 (2x5) or 6 (2x3).

Not sure what the metric system has to do with it, because 'egg' is not exactly an SI unit.

wraith
9th May 2003, 08:35 PM
lol
geez yanks...
get with the program :cool:

BillyJoe
10th May 2003, 06:18 AM
Originally posted by bjornart
A 'four-inch' is a four inch long nail. Do you have a nine inch nail?Originally posted by bjornart
....an 'inch-rod' That's sad. :(Originally posted by bjornart
.....or a 'meter-rod' :eek:

Zep
15th May 2003, 09:16 PM
As for unit pricing, nothing will convince me that a decimal system beats a duodecimal one, simply because of the ability to subdivide twelve four ways as opposed to the two factors of ten. OK, so it is impossible to divide 100 cents into 4 equal parts? :) But agreed, obviously 12 has more prime factors than 10. But then the obvious next question is: Why do you need to do that? Decimal currency countries continue to struggle on just fine without this blessing!

And as for your measurements using metric, you are simply making it too complicated for yourself! Select one unit of measurement and stick to it, don't bother with "conversions" to mixed units - that's just the "imperial" thinking! :) Your tank measures 2095mm - who needs it in metres plus centimetres?

Incidentally, your comment on factors raises a question on US "currency shorthand" I would like confirmed. The US 25 cent coin, the "quarter," is also called "two bits" (I was personally told an item in a shop cost "six bits" or 75 cents). Which would clearly indicate that "one bit" is 12.5 cents, and that there were 8 bits in the dollar (and I have never seen a "one bit" coin in the US!). I believe I know why this nomenclature exists, but I would appreciate first-hand explanation from a numismatist(?) on this board! (You can tell I'm not from North America! :D)

Zep

Ninas grandpa
17th May 2003, 03:04 AM
Originally posted by davefoc
And then there was the fun we didn't get into like that an ounce of water is only .96 fluid ounces or about how precious metals are measured in troy ounces which weigh somewhat more than a regular ounce.

What is it with the US fluid ounce? It took me a long time to work out why a US gallon wasn't exactly 0.8 imperial gallons.

1 US gallon = 8 US pints = 128 fluid ounces
1 imp gallon = 8 imp pints = 160 fluid ounces

and of course it's because the fluid ounces are not the same.

An imperial fluid ounce is defined as the volume of an ounce of water at some temperature (60 degrees f?). What is the definition of a US fluid ounce? (We do use the same ounce don't we?)

UnrepentantSinner
17th May 2003, 09:45 PM
While looking for a precise definition on Enlgish (American) fluid ounce I found this really neat site and wanted to share it.

http://www.unc.edu/~rowlett/units/index.html

allanb
21st May 2003, 05:21 AM
One of the great advantages of the British pre-decimal system was that the diameter of a halfpenny was exactly an inch. So, as long as you had a pocketful of halfpennies, you didn't need to carry a tape measure.

It would be interesting to know whether any decimalised country has such a neat connection between the coinage and the measurement system. Does anyone know?

swellman
23rd May 2003, 10:18 AM
Originally posted by Zep

Incidentally, your comment on factors raises a question on US "currency shorthand" I would like confirmed. The US 25 cent coin, the "quarter," is also called "two bits" (I was personally told an item in a shop cost "six bits" or 75 cents). Which would clearly indicate that "one bit" is 12.5 cents, and that there were 8 bits in the dollar (and I have never seen a "one bit" coin in the US!). I believe I know why this nomenclature exists, but I would appreciate first-hand explanation from a numismatist(?) on this board! (You can tell I'm not from North America! :D)

Zep

It comes from the old Spanish coins called "pieces of eight" by Americans due to an 8 stamped on them.

Interesting article on the subject.

http://www.nctimes.net/news/2001/20010318/aaaa.html

Zep
24th May 2003, 03:21 PM
swellman: It comes from the old Spanish coins called "pieces of eight" by Americans due to an 8 stamped on them. Thanks! I vaguely recalled something very similar from schooldays, but it involved the coin being scored like a pizza so that it was able to be broken into eight pieces, or "bits". But perhaps that was a bit :) more fantastic than reality...!

Zep

rwguinn
24th May 2003, 03:57 PM
Originally posted by swellman

It comes from the old Spanish coins called "pieces of eight" by Americans due to an 8 stamped on them.

Interesting article on the subject.

http://www.nctimes.net/news/2001/20010318/aaaa.html

http://www.coins.nd.edu/ColCoin/ColCoinIntros/Sp-Silver.intro.html

Here's another- rather interesting read on Spanish coinage- and btw- a "half-bit" was known as a "picayune", which is what the New Orleans newspaper charged, and is now part of the NO newspaper name... according to legend, that is

RW

Brown
28th September 2009, 10:16 AM

I have to say that adapting to the metric system was a snap (with one exception, which I'll discuss below). I have little sympathy for those in the US who weep and moan that the metric system is "too hard" to use. Wimps.

The one exception that is still difficult for me to apply is gas mileage for an automobile. (Yes, the term "mileage" is used in Canada.) In the US, the standard unit is miles per gallon: how much distance can you go for a given unit of fuel? In this system, a higher number means more fuel efficient. But in Canada, they approach it differently: given that you need to go 100 kilometers, how many liters of fuel will you need? In this system, a lower number means more fuel efficient.

One nice thing is that if you use old-syle units in Canada (miles, feet and inches, or pounds), no one bats an eye EXCEPT if you mention "gallons." Canada used to use gallons, but its gallon was different from the US gallon.

One interesting side-effect of selling fuel by the liter is that gas stations use the tenth-of-a-cent to compete with one another. Most stations do NOT routinely end their prices with nine-tenths of a cent, as many US stations do. One station might be selling at 87.7 cents per liter, and a competitor across the street might be selling at 87.4 cents per liter. Interesting dynamic.Also, each Kelvin (degree Celsius) is equal to 1.8 degrees Farenheit. Many people are sensitive to temperature changes as small as one degree Farenheit. Until we start speaking in terms of half a degree, using the Farenheit scale makes some sense.I found to my delight that many thermostats in Canada use half-degrees. To do a quick-and-dirty conversion of C-to-F, usually "double it and add thirty" does pretty well. (With ten degrees C, this technique gives EXACTLY the right answer: 50 degrees F.)

Miles-to-kilometers conversions are easy, too. Most people can just look at their speedometer to see a conversion at a glance, but in case a speedometer isn't handy, I just use the Fibbonacci sequence to get a quick-and-dirty estimate.

The Fibbonacci sequence begins 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ... with each number being the sum of the two numbers preceding it. Miles and kilometers are related by two adjoining numbers (and miles and kilometers are approximately within the "golden ratio" with respect to one another).

How much is 55 mph? Just look at the next number in the sequence: 55 mph is about equal to 89 kph. 34 miles is about equal to 55 kilometers. And since 3 mph is approximately 5 kph, 30 mph is approximately 50 kph. If something is 21 km away, it's about 13 miles away. And so on.

Yes, it works with the higher numbers of the Lucas series, too: 1, 3, 4, 7, 11, 18, 29, 47, 76, 123, ...

28th September 2009, 11:07 AM
I have to say that adapting to the metric system was a snap (with one exception, which I'll discuss below). I have little sympathy for those in the US who weep and moan that the metric system is "too hard" to use. Wimps.

I teach at a Canadian college, where nearly all of the students were born well after Canada converted to metric (I know this because I never encountered non-metric units in school, apart from one test which had a question left over from previous years, and I'm much older than most of my students).

Every year, I go over the metric system. Every year, someone whines about miles and pounds being easier.

Even in my math class, when I've spent twenty minutes detailing the historic flaws in the imperial system (like there being 20 different miles across Europe, etc.).

gtc
29th September 2009, 01:17 AM
IOne interesting side-effect of selling fuel by the liter is that gas stations use the tenth-of-a-cent to compete with one another. Most stations do NOT routinely end their prices with nine-tenths of a cent, as many US stations do. One station might be selling at 87.7 cents per liter, and a competitor across the street might be selling at 87.4 cents per liter. Interesting dynamic.

That is interesting. Its rare for me to see anything other than x.9 cents per litre in Australia and our cent is only worth slightly less than a US or Canadian cent.

Shrike
29th September 2009, 03:34 AM
The one exception that is still difficult for me to apply is gas mileage for an automobile. (Yes, the term "mileage" is used in Canada.) In the US, the standard unit is miles per gallon: how much distance can you go for a given unit of fuel? In this system, a higher number means more fuel efficient. But in Canada, they approach it differently: given that you need to go 100 kilometers, how many liters of fuel will you need? In this system, a lower number means more fuel efficient.

I'm not sure if this is metric specific or not. Over here (Holland) we use kilometers per liter, which makes it easier to calculate if you're going to make it to the next gas station (always convenient when the next station is at max 30 km away...). I know the Germans use the same system as the Canadians.

Funny story aside. A colleague of mine was visiting the US and Canada. After crossing the border into Canada he came unto a corner with the warning 30. Now, he made two mistakes. He had found the Americans notoriously careful with speeds in corners, so he thought he could take it with 50. Now, mistake number 2 was that he was still thinnking in miles per hour and had forgotten that Canada was metric.
He just managed to take the curve without crashing.

29th September 2009, 05:22 AM
Didn't a Mars mission crash because somebody mistook an inch for a cm, or is that an urban legend? Hundred million dollar mistakes like that seem a good argument for metric conversion.

............ I still miss my 'kwartje' (quarter) those 20 eurocent coins are just silly

we also used to have nice 'rijksdaalders' (fl 2,50 ) , now we have €2,- Funny thing: €2 is about fl 4,40 but still a rijksdaalder used to feel like more money. But that is propably because my financial situation changed a lot around the time when we got the euro. (I started working)

Shrike
29th September 2009, 05:44 AM
But that is propably because my financial situation changed a lot around the time when we got the euro. (I started working)

So did mine. I got kids (:(, but only on the financial side).

Fishstick
29th September 2009, 05:52 AM
I'm not sure if this is metric specific or not. Over here (Holland) we use kilometers per liter, which makes it easier to calculate if you're going to make it to the next gas station (always convenient when the next station is at max 30 km away...). I know the Germans use the same system as the Canadians.
.

Odd. We in Belgium also use X Litre/100km, same for CO emissions (X g/100km)

Shrike
29th September 2009, 06:01 AM
Odd. We in Belgium also use X Litre/100km, same for CO emissions (X g/100km)

Sorry, yeah.
Officially we do. Normal people speaking to each other (:)) use the other notation.

29th September 2009, 06:53 AM
Probably the worst thiing about non-SI units is that there are very often more then one of them. Tons come in metric, short and long; gallons in imperial and US; pounds are avoirdupois or Troy or perhaps sterling (giggle), ounces are dry or wet; miles are statute or nautical, and so on. I suppose that has something to do with the fact that they came into use before they were standardized. That in itself is enough reason to abandon them.

My favorite bad weights-and-measures story has to do with architecture. I did a spell in architectural software. In metric countries all linear measurements on plans (except for gross land) is done in millimeters. No units given on the drawings, none needed as mms were always assumed, and no decimals - all very neat and easy to comprehend, and able for instant conversion to meters or whatever in one's head. In the US, linear measurements could have been in inches (with a decimal fraction, perhaps), or perhaps even in feet, but no, official drawnings must be in feet, inches (0-11) and fractions thereof, where the only allowed fractions are of powers of 2: 1/2, 3/4, 5/8, and so on, thus: 5'-7 3/8" (i.e., 1711 (mm)). The software to handle that was really kean.

Cuddles
29th September 2009, 09:04 AM
like there being 20 different miles across Europe

I could have sworn Europe was bigger than that.:)

Didn't a Mars mission crash because somebody mistook an inch for a cm, or is that an urban legend? Hundred million dollar mistakes like that seem a good argument for metric conversion.

Yep (http://en.wikipedia.org/wiki/Mars_Climate_Orbiter). To be fair, it wasn't quite someone mixing them up. NASA had actually converted to metric, but Lockheed Martin used imperial, which led to some fun problems in the software controlling the thrusters.

The sad part is that rather sticking with the sensible system and just checking the units (which you'd rather hope they'd be doing anyway), they decided to go back to imperial.

Brown
29th September 2009, 09:41 AM
I'm not sure if this is metric specific or not. Over here (Holland) we use kilometers per liter, which makes it easier to calculate if you're going to make it to the next gas station (always convenient when the next station is at max 30 km away...). I know the Germans use the same system as the Canadians.The following is hearsay at best, and may be urban legend... but it has a degree of truth in it.

What I was told was, when Canada went fully metric, the distance-per-amount measurement of kilometers-per-liter seemed ridiculously LOW when compared to the US measurement of miles-per-gallon. Having a car that gets 15 kilometers per liter SOUNDS much less efficient than a car getting 30 miles per gallon.

So, to avoid unfair comparisons with the US, Canada decided to use a "lower is better" system.

29th September 2009, 11:28 AM
I could have sworn Europe was bigger than that.

"Different" miles. Some European miles were about half a kilometre; the Norwegian one was 10 km.

HeyLeroy
29th September 2009, 12:20 PM
Here in Windsor, Ontario (just south of Detroit) we speak both metric and imperial. In our local paper criminal suspects are still described in feet, inches and pounds.

I still haven't figured out how many furlongs per hogshead my car gets, though.

bjornart
29th September 2009, 12:34 PM
"Different" miles. Some European miles were about half a kilometre; the Norwegian one was 10 km.

Actually before 1889 a Norwegian mile was 11,295 m and a Swedish one was 10,688.54 m. The 1889 decision meant we got a single and metric compatible definition. We still use it for mileage in everyday speak, in the liters per mile fashion. But since all the numbers in ads and brochures come from international manufacturers in liters per 100 km we have to make complex calculations in our heads to compare them with our own experience.

anor277
30th September 2009, 09:05 PM
One area where the metric system leaves a bit to be desired are the units of pressure; and the use of metric units for pressure measurement is much less widespread than it is for say length and mass. Now (for mine) the most intuitive unit of pressure is the atmosphere (it's readily and visibly measured, 1 atm = 760 mm Hg column length on a barometer); on the other hand the SI unit of pressure is the Pascal, 1 Pascal (Pa) = 1 Nm-2. There are 101.3 kPa per atmosphere; to make matters a bit simpler some pressure measurement is done in bars (1 bar = 100 kPa, not quite an atmosphere! but defined to be a standard laboratory condition).

To this day you can find many gas regulators (even in Europe) calibrated in the old psig (1 atm = 14.7 pounds per square inch); I still find myself thinking in 2-3 psig for overpressures of gas. It would make (my!) life a bit simpler if we switched to atmospheres.

Cuddles
2nd October 2009, 07:36 AM
One area where the metric system leaves a bit to be desired are the units of pressure; and the use of metric units for pressure measurement is much less widespread than it is for say length and mass. Now (for mine) the most intuitive unit of pressure is the atmosphere (it's readily and visibly measured, 1 atm = 760 mm Hg column length on a barometer); on the other hand the SI unit of pressure is the Pascal, 1 Pascal (Pa) = 1 Nm-2. There are 101.3 kPa per atmosphere; to make matters a bit simpler some pressure measurement is done in bars (1 bar = 100 kPa, not quite an atmosphere! but defined to be a standard laboratory condition).

To this day you can find many gas regulators (even in Europe) calibrated in the old psig (1 atm = 14.7 pounds per square inch); I still find myself thinking in 2-3 psig for overpressures of gas. It would make (my!) life a bit simpler if we switched to atmospheres.

Why not just use bar?

Ryokan
4th October 2009, 12:44 PM
and those of us of Scandinavian descent still make cookies that are not often seen on Norwegian nor Swedish tables at Christmas (got this from a conversation with Swedish Cadets from a training vessel "Alvsnabben" (? sp) when we asked them about Fatigmann and Sandbuckles) ---

Don't know what a Sandbuckle is, but my grandma still makes Fattigmen :)

In Norway, at least, what cakes, cookies and dinner is made for christmas varies a lot from area to area.

ZirconBlue
4th October 2009, 05:34 PM
Don't know what a Sandbuckle is, but my grandma still makes Fattigmen :)

In Norway, at least, what cakes, cookies and dinner is made for christmas varies a lot from area to area.

No, no, no, no, no. "Norway" is a single monolithic culture with universal social customs.

Like orcs, goblins, or kobolds.

4th October 2009, 06:53 PM
No, no, no, no, no. "Norway" is a single monolithic culture with universal social customs.

Then explain how they can have 4.3 million dialects with a population of 4.1 million.

ZirconBlue
5th October 2009, 09:37 AM
Then explain how they can have 4.3 million dialects with a population of 4.1 million.

Outsourcing.

bjornart
7th October 2009, 12:48 PM
Don't know what a Sandbuckle is, but my grandma still makes Fattigmen :)

In Norway, at least, what cakes, cookies and dinner is made for christmas varies a lot from area to area.

I'm gonna guess Sandbuckles are sandkaker. And google proves me right.

ZirconBlue
7th October 2009, 06:14 PM
I'm gonna guess Sandbuckles are sandkaker. And google proves me right.

That clears up absolutely nothing. Thanks.

I guess.

Ryokan
10th October 2009, 11:58 AM
I'm gonna guess Sandbuckles are sandkaker. And google proves me right.

In that case, grandma makes those as well!

So his mistake was, as any Norwegian could've told him, he talked to a Swede!

ZirconBlue
10th October 2009, 04:30 PM
In that case, grandma makes those as well!

So his mistake was, as any Norwegian could've told him, he talked to a Swede!

Who said, "um-bork, bork, bork."

Ryokan
10th October 2009, 06:56 PM
I see now, btw, that I've been replying to a 6 year old conversation...