Fuel efficiency or fuel consumption units
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Mark Brader - 17 Dec 2008 00:18 GMT In the US it is customary to measure the fuel efficiency of a car in units of miles per (US) gallon or MPG. And here in Canada when I was a boy, we also used MPG (but with Imperial gallons, of course).
Today our government has opted to have us use fuel consumption units, the reciprocal of fuel efficiency, and specifically they have chosen the non-SI metric unit of liters per hundred kilometers or L/100 km.
What I want to know now is, how were these things measured in Britain or other Commonwealth countries before the adoption of metric measure? Was it miles per (Imperial) gallon or something else? I asked my father already, but he doesn't remember the subject coming up at all before we moved to Canada in 1957.
And does anyone remember a metric measure other than L/100 km ever being customary for this purpose where they lived? In particular, did people ever use kilometers per liter (km/L) in Canada, Britain, or other countries, or do they now?
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DavidW - 17 Dec 2008 01:22 GMT > In the US it is customary to measure the fuel efficiency of a car in > units of miles per (US) gallon or MPG. And here in Canada when I was [quoted text clipped - 14 lines] > did people ever use kilometers per liter (km/L) in Canada, Britain, > or other countries, or do they now? Australia uses L/100 km. AFAIK it came in with the metric system, which was a long time ago.
The metric system is not very practical for everyday use IMO. The units have too many syllables and sound too technical. Use them in science but stick with imperial for the general population. It's far too late for Australia, though, of course.
James Silverton - 17 Dec 2008 01:56 GMT DavidW wrote on Wed, 17 Dec 2008 12:22:30 +1100:
>> In the US it is customary to measure the fuel efficiency of a >> car in units of miles per (US) gallon or MPG. And here in [quoted text clipped - 17 lines] >> particular, did people ever use kilometers per liter (km/L) >> in Canada, Britain, or other countries, or do they now?
> Australia uses L/100 km. AFAIK it came in with the metric > system, which was a long time ago. If English speakers would really use the metric system, the situation could be improved. Klicks, mils, kilos and liters (and the lasty two are universal) are not that burdensome. For cars, acceleration 0-100kph is not much different from 0-60mph.
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Mike Barnes - 17 Dec 2008 10:35 GMT In alt.usage.english, James Silverton wrote:
>For cars, acceleration 0-100kph is not much different from 0-60mph. Agreed. The UK car trade, when measuring acceleration, uses 0-100kph times but usually calls then "0-60". This is because test results are generally for Europe-wide consumption. The measure is fairly meaningless and certainly doesn't suffer from the difference between 60 and 62.
 Signature Mike Barnes Cheshire, England
Prai Jei - 17 Dec 2008 19:16 GMT DavidW set the following eddies spiralling through the space-time continuum:
> The metric system is not very practical for everyday use IMO. The units > have too many syllables and sound too technical. Use them in science but > stick with imperial for the general population. It's far too late for > Australia, though, of course. The EU has just ruled that we can keep our Imperial units in use. We have survived several attempts to abolish them but now they are (as they always were) sacrosanct.
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John Holmes - 21 Dec 2008 10:12 GMT >> And does anyone remember a metric measure other than L/100 km ever >> being customary for this purpose where they lived? In particular, [quoted text clipped - 3 lines] > Australia uses L/100 km. AFAIK it came in with the metric system, > which was a long time ago. And before that (up to the early 1970s) it was mpg. I've never seen any other unit in common use anywhere.
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Don Phillipson - 17 Dec 2008 01:40 GMT > What I want to know now is, how were these things measured in Britain > or other Commonwealth countries before the adoption of metric measure? The British measure (before petrol was sold in litres) was m.p.g. = (statute) miles per (imperial) gallon.
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Appelation Controlee - 20 Dec 2008 12:19 GMT >> What I want to know now is, how were these things measured in Britain >> or other Commonwealth countries before the adoption of metric measure? > > The British measure (before petrol was sold in litres) was m.p.g. > = (statute) miles per (imperial) gallon. m.p.g. is the figure that's still quoted. We fill our cars in litres, odometers record miles driven, speeds (and enforcement legislation) are in m.p.h., and all our road sign distances show miles. A bit of a mess really.
Peter Duncanson (BrE) - 20 Dec 2008 12:57 GMT >>> What I want to know now is, how were these things measured in Britain >>> or other Commonwealth countries before the adoption of metric measure? [quoted text clipped - 6 lines] >m.p.h., and all our road sign distances show miles. >A bit of a mess really. A mess, but not a problem.
The m.p.g figures are used primarily for comparison when choosing a car so the absolute meaning of the units don't really matter.
 Signature Peter Duncanson, UK (in alt.usage.english)
J. J. Lodder - 20 Dec 2008 13:32 GMT > >>> What I want to know now is, how were these things measured in Britain > >>> or other Commonwealth countries before the adoption of metric measure? [quoted text clipped - 11 lines] > The m.p.g figures are used primarily for comparison when choosing a car so the > absolute meaning of the units don't really matter. Brits being what they are it seems quite likely that they will still be using 'mpg' when hardly anybody remembers what a mile and a gallon were,
Jan
Mike Barnes - 20 Dec 2008 15:58 GMT In alt.usage.english, J. J. Lodder wrote:
>> The m.p.g figures are used primarily for comparison when choosing a >>car so the [quoted text clipped - 4 lines] >when hardly anybody remembers >what a mile and a gallon were, I think that sort of thing is human nature generally rather than being specifically British. ISTR that the Dutch "pond" still exists. Wikipedia says it's officially defined as 1 kilogram but in daily use it actually means 500 grams.
 Signature Mike Barnes Cheshire, England
James Silverton - 20 Dec 2008 18:05 GMT Mike wrote on Sat, 20 Dec 2008 15:58:16 +0000:
> In alt.usage.english, J. J. Lodder wrote: >> [quoted text clipped - 6 lines] >> when hardly anybody remembers >> what a mile and a gallon were,
> I think that sort of thing is human nature generally rather > than being specifically British. ISTR that the Dutch "pond" > still exists. Wikipedia says it's officially defined as 1 > kilogram but in daily use it actually means 500 grams. On a trip to Europe, just a few years ago, I came across "livre" and "pfund" with the same meaning: 500g.
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John Varela - 21 Dec 2008 23:44 GMT > In alt.usage.english, J. J. Lodder wrote: >> [quoted text clipped - 11 lines] > says it's officially defined as 1 kilogram but in daily use it actually > means 500 grams. Tsk tsk. You fail to understand the innate superiority of Dutch culture.
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J. J. Lodder - 22 Dec 2008 09:57 GMT > > In alt.usage.english, J. J. Lodder wrote: > >> [quoted text clipped - 14 lines] > Tsk tsk. You fail to understand the innate superiority of Dutch > culture. I don't want to bother you with historical trivialities of course, but the brilliant idea of renaming the kilogram to livre/pond/pfund is due to none other than the great Napoleon Bonaparte, (who also abolished the metric system in France)
Jan
J. J. Lodder - 22 Dec 2008 09:57 GMT > In alt.usage.english, J. J. Lodder wrote: > > [quoted text clipped - 9 lines] > I think that sort of thing is human nature generally rather than being > specifically British. ISTR that the Dutch "pond" still exists. Not only exists, in every day use. Asking for 'een pond kaas' will produce the desired result. Of course, Dutch being what it is, 'een pondje ...' wil also work.
> Wikipedia says it's officially defined as 1 kilogram > but in daily use it actually means 500 grams. An error in wiki,
Jan
Appelation Controlee - 20 Dec 2008 16:40 GMT >>>>> What I want to know now is, how were these things measured in Britain >>>>> or other Commonwealth countries before the adoption of metric measure? [quoted text clipped - 13 lines] > > Brits being what they are ... Generalisations are seldom universally true. ;-)
Robert Lieblich - 20 Dec 2008 16:46 GMT [ ... ]
> Brits being what they are it seems quite likely > that they will still be using 'mpg' > when hardly anybody remembers > what a mile and a gallon were, And even if the Brits drop the units, we Americans will still be carrying on in them indefinitely. Don't we still use "gotten"?
-- Bob Lieblich Who weighs about 17 stone
John Varela - 20 Dec 2008 18:03 GMT > [ ... ] > [quoted text clipped - 9 lines] > Bob Lieblich > Who weighs about 17 stone Even the Flying Dutchman measured distance in nautical miles and speed in knots.
Your sig line seems to be missing a space after the --.
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J. J. Lodder - 22 Dec 2008 09:57 GMT > > [ ... ] > > [quoted text clipped - 12 lines] > Even the Flying Dutchman measured distance in nautical miles and speed > in knots. Flying Dutchmen still do,
Jan
Chuck Riggs - 21 Dec 2008 12:51 GMT >[ ... ] > [quoted text clipped - 5 lines] >And even if the Brits drop the units, we Americans will still be >carrying on in them indefinitely. Don't we still use "gotten"? And don't the Irish?
http://www.quotesdaddy.com/quote/1378405/monsignor-eugene-oconnor/we-havent-gott en-any-new-priests-from-ireland-for
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Hatunen - 21 Dec 2008 20:47 GMT >[ ... ] > [quoted text clipped - 5 lines] >And even if the Brits drop the units, we Americans will still be >carrying on in them indefinitely. Don't we still use "gotten"? Unfortunately, of course, it's not the same gallon.
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Garrett Wollman - 22 Dec 2008 03:43 GMT >>And even if the Brits drop the units, we Americans will still be >>carrying on in them indefinitely. Don't we still use "gotten"? > >Unfortunately, of course, it's not the same gallon. But that's *their* fault for changing their gallon. *We* still have the proper-sized ones.
-GAWollman
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Ian Jackson - 22 Dec 2008 15:54 GMT >>>And even if the Brits drop the units, we Americans will still be >>>carrying on in them indefinitely. Don't we still use "gotten"? [quoted text clipped - 5 lines] > >-GAWollman I've always suspected that the reason for the US Gallon being 20% less than the Imperial Gallon is due to some unscrupulous early settlers started selling short-measure to the local inhabitants. Am I just being cynical?
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Peter Duncanson (BrE) - 22 Dec 2008 15:59 GMT >>>>And even if the Brits drop the units, we Americans will still be >>>>carrying on in them indefinitely. Don't we still use "gotten"? [quoted text clipped - 10 lines] >started selling short-measure to the local inhabitants. Am I just being >cynical? If they were also using the 80% gallon among themselves then no one was being short-measured.
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Ian Jackson - 22 Dec 2008 20:14 GMT >>I've always suspected that the reason for the US Gallon being 20% less >>than the Imperial Gallon is due to some unscrupulous early settlers [quoted text clipped - 3 lines] >If they were also using the 80% gallon among themselves then no one was being >short-measured. But, if they weren't, they were.
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Roland Hutchinson - 22 Dec 2008 16:18 GMT >>>>And even if the Brits drop the units, we Americans will still be >>>>carrying on in them indefinitely. Don't we still use "gotten"? [quoted text clipped - 8 lines] > I've always suspected that the reason for the US Gallon being 20% less > than the Imperial Gallon We've done this before.
The US gallon isn't 20% less than the imperial gallon; it contains 20% fewer ounces, but the ounces are slightly larger.
The imperial gallon is, however, (to slide-rule accuracy) 20% larger than the US gallon.
> is due to some unscrupulous early settlers > started selling short-measure to the local inhabitants. Am I just being > cynical? Back when the Empire was a-forming, apparently there were several kinds of gallon. What became the US gallon was the wine gallon, or somewhat.
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Appelation Controlee - 27 Dec 2008 09:29 GMT >>>>>And even if the Brits drop the units, we Americans will still be >>>>>carrying on in them indefinitely. Don't we still use "gotten"? [quoted text clipped - 12 lines] > The US gallon isn't 20% less than the imperial gallon; it contains 20% fewer > ounces, but the ounces are slightly larger. I thought the ounces were the same, there being 16 to the US pint. (?)
Peter Duncanson (BrE) - 27 Dec 2008 11:12 GMT >>>>>>And even if the Brits drop the units, we Americans will still be >>>>>>carrying on in them indefinitely. Don't we still use "gotten"? [quoted text clipped - 14 lines] > >I thought the ounces were the same, there being 16 to the US pint. (?) Almost the same, but not quite.
http://en.wikipedia.org/wiki/Fluid_ounce
Imperial fluid ounce = 28.4130625 millilitres (exactly) = 0.960759940 U.S. fluid ounces
U.S. fluid ounce = 29.5735295625 millilitres (exactly) = 1.040842731 imperial fluid ounces
 Signature Peter Duncanson, UK (in alt.usage.english)
Ian Jackson - 27 Dec 2008 12:12 GMT >>>>>>>And even if the Brits drop the units, we Americans will still be >>>>>>>carrying on in them indefinitely. Don't we still use "gotten"? [quoted text clipped - 26 lines] > = 29.5735295625 millilitres (exactly) > = 1.040842731 imperial fluid ounces Well blow me down! I always thought that they were identical.
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J. J. Lodder - 27 Dec 2008 15:35 GMT > >>>>>>>And even if the Brits drop the units, we Americans will still be > >>>>>>>carrying on in them indefinitely. Don't we still use "gotten"? [quoted text clipped - 28 lines] > > > Well blow me down! I always thought that they were identical. Why? That would be too simple,
Jan
Appelation Controlee - 28 Dec 2008 06:10 GMT -------------------8><
>>>I thought the ounces were the same, there being 16 to the US pint. (?) >> [quoted text clipped - 11 lines] >> > Well blow me down! I always thought that they were identical. Me too - shaken to the core. :^)
Pat Durkin - 28 Dec 2008 07:31 GMT > -------------------8>< >>>> I thought the ounces were the same, there being 16 to the US pint. [quoted text clipped - 15 lines] > > Me too - shaken to the core. :^) Ditto. I never bothered with that stuff, and am shocked, (shocked) to see US units are larger than Imperial units.
Hatunen - 31 Dec 2008 19:39 GMT >-------------------8>< >>>>I thought the ounces were the same, there being 16 to the US pint. (?) [quoted text clipped - 14 lines] > >Me too - shaken to the core. :^) It then being known that a Canadian quart had 40 ounces while a US quart was 32 ounces, when I was young travelers to Canada were usually under the impression that a Canadian gallon was also in a 5:4 ratio with the American gallon, and it was hard to persuade them the ratio was more like 6:5.
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Ian Jackson - 27 Dec 2008 11:56 GMT >>>>>>And even if the Brits drop the units, we Americans will still be >>>>>>carrying on in them indefinitely. Don't we still use "gotten"? [quoted text clipped - 14 lines] > >I thought the ounces were the same, there being 16 to the US pint. (?) Surely ounces are ounces? And 16 ounces in a pound. It's only the liquid measures which are different.
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Richard Yates - 27 Dec 2008 12:41 GMT >>>>>>> And even if the Brits drop the units, we Americans will still be >>>>>>> carrying on in them indefinitely. Don't we still use "gotten"? [quoted text clipped - 18 lines] > Surely ounces are ounces? And 16 ounces in a pound. It's only the > liquid measures which are different. Maybe the density of water is different over there!
Ian Jackson - 27 Dec 2008 13:50 GMT >>>>>>>> And even if the Brits drop the units, we Americans will still be >>>>>>>> carrying on in them indefinitely. Don't we still use "gotten"? [quoted text clipped - 20 lines] > >Maybe the density of water is different over there! Well, apparently Americans are more hot-blooded than the British. Their standard 'blood heat' is 98.6F. Ours is (or was, when I was a lad) 98.4F.
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Robert Bannister - 27 Dec 2008 21:43 GMT > Well, apparently Americans are more hot-blooded than the British. Their > standard 'blood heat' is 98.6F. Ours is (or was, when I was a lad) 98.4F. Isn't this something to do with standardisation? When I was a lad, blood temperature in Celsius was 36.7°, but now it's exactly 37°. Whether the first was simply a conversion from F to C, I don't know.
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Rob Bannister
Leslie Danks - 27 Dec 2008 22:00 GMT >> Well, apparently Americans are more hot-blooded than the British. Their >> standard 'blood heat' is 98.6F. Ours is (or was, when I was a lad) 98.4F. > > Isn't this something to do with standardisation? When I was a lad, blood > temperature in Celsius was 36.7°, but now it's exactly 37°. Whether the > first was simply a conversion from F to C, I don't know. This may shed light on the matter: <http://hypertextbook.com/facts/LenaWong.shtml>
"For decades it was thought that the normal body temperature was 98.6 °F. This number was calculated from a study in Germany which reported normal at 37 °C. What was not known was that this number was an average rounded to the nearest degree. In other words it was only accurate to two significant digits, not the three we have with 98.6. Scientists today know that normal is actually 98.2 plus or minus 0.6, that is to say anything in the range of 97.6° to 98.8° should be considered normal."
(In other words, anything between 36.4 and 37.1 °C)
The temperature actually measured varies with time of day, sex, ethnicity and method used (oral, rectal, ear canal, armpit). The above link will tell you more than you want to know.
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Peter Duncanson (BrE) - 27 Dec 2008 14:13 GMT >>>>>>>> And even if the Brits drop the units, we Americans will still be >>>>>>>> carrying on in them indefinitely. Don't we still use "gotten"? [quoted text clipped - 20 lines] > >Maybe the density of water is different over there! For normal purposes water is incompressible so the following will not affect the density.
The force of gravity, hence weight, varies from place to place on the Earth's surface. <http://en.wikipedia.org/wiki/Earth%27s_gravity#Comparative_gravities_in_various_ cities_around_the_world> or http://tinyurl.com/2ftwyq
In the early 1960s my father was a visiting examiner for the University of London overseeing degree-level physics exams at a college in West Africa.
He was worried that in a practical exam all the students had apparently failed to measure the correct value of g. It took some time for him to realise that they had in fact got close to the local value of g. As he said, if anyone had asked him whether g had a fixed value everywhere on the surface of the Earth he would have immediately said no, but he had never previously seen the differences "on the ground".
 Signature Peter Duncanson, UK (in alt.usage.english)
Steve Hayes - 27 Dec 2008 22:01 GMT >In the early 1960s my father was a visiting examiner for the University of >London overseeing degree-level physics exams at a college in West Africa. [quoted text clipped - 5 lines] >he would have immediately said no, but he had never previously seen the >differences "on the ground". But a g is a measure of mass, not weight, and will therefore be the same whether on earth or in outer space.
Isn't weight measured in n?
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R H Draney - 27 Dec 2008 22:08 GMT Steve Hayes filted:
>>In the early 1960s my father was a visiting examiner for the University of >>London overseeing degree-level physics exams at a college in West Africa. [quoted text clipped - 10 lines] > >Isn't weight measured in n? g is an acceleration and is independent of mass....r
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Hatunen - 28 Dec 2008 02:07 GMT >>In the early 1960s my father was a visiting examiner for the University of >>London overseeing degree-level physics exams at a college in West Africa. [quoted text clipped - 8 lines] >But a g is a measure of mass, not weight, and will therefore be the same >whether on earth or in outer space. As Draney points out, g is an acceleration, not a mass.
>Isn't weight measured in n? N. In metric/SI. Newtons are a force, as are pounds.
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Mark Brader - 28 Dec 2008 05:26 GMT Peter Duncanson:
>>> He was worried that in a practical exam all the students had >>> apparently failed to measure the correct value of g. ... Steve Hayes:
>> But a g is a measure of mass, not weight, and will therefore be the same >> whether on earth or in outer space. Dave Hatunen:
> As Draney points out, g is an acceleration, not a mass. Let's make things explicit in case anyone is actually confused here.
In the SI (metric system) the symbol for the gram, a unit of mass, is g. This is normally used as in "6 g", meaning (and pronounced) "six grams". (In Britain they haven't yet learned that the space between the numeral and the unit symbol is required.) This "g" is not used by itself as a noun as in "g is a measure of mass".
On the other hand, the conventional symbol for the acceleration due to gravity at the Earth's surface is also "g". This is basically a measured or calcaulated quantity and not a unit; it shows up as a variable in formulas, where it is written in italics if possible. However, it is sometimes used as a unit, and in this usage sometimes capitalized: "6 g" or "6 G" (pronounced "six gees" or "six gravities") in this usage means an acceleration of 6g, where g is the variable..
>> Isn't weight measured in n? > > N. In metric/SI. Newtons are a force, Again, it's not proper to use the symbol as a noun like that. Weight is measured in newtons, which are a *unit of* force.
> as are pounds. Wrong, even though some of us learned it that way in school.
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R H Draney - 28 Dec 2008 08:01 GMT Mark Brader filted:
>On the other hand, the conventional symbol for the acceleration due >to gravity at the Earth's surface is also "g". This is basically a [quoted text clipped - 3 lines] >capitalized: "6 g" or "6 G" (pronounced "six gees" or "six gravities") >in this usage means an acceleration of 6g, where g is the variable.. But it *shouldn't* be capitalized, because G is the "gravitational constant", a quantity approximately equal to 6.67428E-11 m^3 kg^-1 s^-2...unlike little g, there's no "local value" of big G....r
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Mark Brader - 28 Dec 2008 19:59 GMT Mark Brader:
>> On the other hand, the conventional symbol for the acceleration due >> to gravity at the Earth's surface is also "g". ... >> However, it is sometimes used as a unit, and in this usage sometimes >> capitalized ... R.H. Draney:
> But it *shouldn't* be capitalized, because G is the "gravitational > constant", a quantity approximately equal to 6.67428E-11 m^3 kg^-1 s^-2 Yes, well, just as with the other two g's, there is rarely any ambiguity.
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R H Draney - 29 Dec 2008 02:13 GMT Mark Brader filted:
>Mark Brader: >>> On the other hand, the conventional symbol for the acceleration due [quoted text clipped - 7 lines] > >Yes, well, just as with the other two g's, there is rarely any ambiguity. Ordinarily I'd agree, but since all three have at least something to do with "heft", there's always a slight risk....
It's not like confusing "K" for "Kelvins" with "K" for "potassium" and "k" for "multiples of a thousand" with "k" for "an arbitrary constant"....r
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Hatunen - 31 Dec 2008 19:36 GMT >Peter Duncanson: >>>> He was worried that in a practical exam all the students had [quoted text clipped - 33 lines] > >Wrong, even though some of us learned it that way in school. Wrong. "Pound" is a unit of force. An object that weighs six pounds on the earth will weigh about one pound on the moon, wieght being measured as a force. The term "pound" is sometimes used as a unit of mass, but to eliminate ambiguity it should be clear that it is the pound-mass(lbm) and not the pound-force(lbf) being referred to. Using it as the pound-mass causes confusion when applying formulas like F = ma. If the unit of mass is the pound-mass, the force F is measured in poundals, a unit rarely seen in public.
The usual unit of mass is the slug, which "weighs" about 32 pounds. A force of one pound applied to a mass of one slug will accelerate it at 1 ft/s*2. One rarely sees the slug mass in public either, and engineers have always been trained that mass = W/g which is rather freely stuck into calculations with no real thought of slugs although W/g is slugs (W being weight on earth).
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John Holmes - 01 Jan 2009 07:22 GMT >> Wrong, even though some of us learned it that way in school. > [quoted text clipped - 14 lines] > W/g which is rather freely stuck into calculations with no real > thought of slugs although W/g is slugs (W being weight on earth). I dimly remember hearing of slugs and poundals at high school in the 1960s, along with a few other obsolete units I've forgotten. I've never encountered them in real life working in applied scince and engineering. Are they really still used anywhere?
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Hatunen - 01 Jan 2009 18:50 GMT >>> Wrong, even though some of us learned it that way in school. >> [quoted text clipped - 19 lines] >encountered them in real life working in applied scince and engineering. >Are they really still used anywhere? Slugs are implicit everytime you use W/g in an equation.
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Mark Brader - 01 Jan 2009 11:54 GMT Dave Hatunen:
>>> [Pounds are a unit of force]. Mark Brader:
>> Wrong, even though some of us learned it that way in school. Dave Hatunen:
> Wrong. You have learned well what they taught you in school, but it's still wrong. A pound is defined as 0.45359237 kilogram. Look it up.
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Hatunen - 01 Jan 2009 19:51 GMT >Dave Hatunen: >>>> [Pounds are a unit of force]. [quoted text clipped - 7 lines] >You have learned well what they taught you in school, but it's still >wrong. A pound is defined as 0.45359237 kilogram. Look it up. That's the pound mass; see http://en.wikipedia.org/wiki/Pound_(mass)
That's the sort of thing that causes the confusion, since a pound mass doesn't weigh a pound on the moon, nor exactly a pound much of anywhere on earth, for that matter. Of course, you can establish its mass as one pound using a balance scale on the moon, since a balance scale compares masses not weights, but a spring scale won't give you a pound, so obviously the spring scale and the balance scale measure different things.
Commodities are generally sold by mass, which is constant despite the local acceleration of gravity, and proper measurement generally requires the use of balance scales. So commerce requires the pound mass to be tied to a standard mass such as the kilogram.
This dual role has been the bane of engineering students in the USA for a long time, and when I first went to engineering school in 1954 even the physics classes were taught in the pound-foot-second system so it was confusing there, as well.
Even the use of the kilogram to indicate weight can be a problem, since weight is more properly measured in Newtons. A Newton, as a kilogram-meter-per second squared yields easy answers. Apply a force of one Newton to a mass of one kilogram and the mass accelerates at 1 m/s*2. Apply a kilogram-force, say by hanging a kg mass on a rope and using the rope to pull a kilogram mass and, well, what is the acceleration of the pulled mass?
Of course, in everyday life it matters little whether an object has a mass of a pound or a weight of a pound since anywhere on earth the values will be the same within human sensibility and very few people in their everyday lives have occasion to apply the Newtonian formula F = ma to any great precision. And I doubt that many Europeans will begin to express weight in Newtons; The Brits can's seem to even get rid of the stone.
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Mark Brader - 02 Jan 2009 05:14 GMT Mark Brader:
>> You have learned well what they taught you in school, but it's still >> wrong. A pound is defined as 0.45359237 kilogram. Look it up. Dave Hatunen:
> That's the pound mass... That's right, the pound is defined to be what is also called the pound mass.
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Hatunen - 02 Jan 2009 19:54 GMT >Mark Brader: >>> You have learned well what they taught you in school, but it's still [quoted text clipped - 4 lines] > >That's right, the pound is defined to be what is also called the pound mass. That's what I said.
But the pound also exists as the pound force.
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Mark Brader - 02 Jan 2009 23:37 GMT Mark Brader:
>> That's right, the pound is defined to be what is also called the pound mass. Dave Hatunen:
> That's what I said. > But the pound also exists as the pound force. No, you said that pounds are a force unit. Pounds are a mass unit. Using "pound" to mean "pound force" is only acceptable informally or within the context of a nonstandard system.
 Signature Mark Brader And now write us Toronto A devious quasipoem! msb@vex.net --Richard Heathfield
Hatunen - 03 Jan 2009 00:31 GMT >Mark Brader: >>> That's right, the pound is defined to be what is also called the pound mass. [quoted text clipped - 6 lines] >Using "pound" to mean "pound force" is only acceptable informally or >within the context of a nonstandard system. You win...
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Garrett Wollman - 03 Jan 2009 04:19 GMT >No, you said that pounds are a force unit. Pounds are a mass unit. >Using "pound" to mean "pound force" is only acceptable informally or >within the context of a nonstandard system. Nonsense.
"Pound" means what other English speakers use it to mean, just like every other word in the language. A formal standard issued by some body or other is not some magic artifact that suddenly freezes the meaning of every word it purports to define.
-GAWollman
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Mark Brader - 05 Jan 2009 22:02 GMT Mark Brader:
>> Using "pound" to mean "pound force" is only acceptable informally or >> within the context of a nonstandard system. Garrett Wollman:
> Nonsense. That seems a bit strong, considering that when you say
> "Pound" means what other English speakers use it to mean, just like > every other word in the language. A formal standard issued by some > body or other is not some magic artifact that suddenly freezes the > meaning of every word it purports to define. you are agreeing with me. The word is defined by a formal standard (specifically, by law), and other uses therefore exist only in informal or nonstandard contexts. The earlier conversation was within the context of standardized usage.
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Garrett Wollman - 05 Jan 2009 22:15 GMT >you are agreeing with me. The word is defined by a formal standard >(specifically, by law), and other uses therefore exist only in >informal or nonstandard contexts. The earlier conversation was >within the context of standardized usage. Methinks you are conflating two meanings of "formal".
-GAWollman
 Signature Garrett A. Wollman | The real tragedy of human existence is not that we are wollman@csail.mit.edu| nasty by nature, but that a cruel structural asymmetry Opinions not those | grants to rare events of meanness such power to shape of MIT or CSAIL. | our history. - S.J. Gould, Ten Thousand Acts of Kindness
Glenn Knickerbocker - 05 Jan 2009 23:30 GMT > you are agreeing with me. The word is defined by a formal standard > (specifically, by law) Fortunately, lawyers aren't the arbiters of standards of English usage. And I don't know what country's law you're talking about, but US Title 15, while it defines the pound and ounce in terms of mass since 1959, still consistently calls them weights.
¬R
Glenn Knickerbocker - 05 Jan 2009 23:31 GMT I wrote:
> Fortunately, lawyers aren't the arbiters of standards of English usage. I meant to add that legislators aren't, either.
¬R
Mark Brader - 06 Jan 2009 10:41 GMT > And I don't know what country's law you're talking about, It doesn't matter. There's an international agreement between the relevant countries -- for example, the US, UK, and Canada -- implemented in each country via its own laws.
> but US Title 15, while it defines the pound and ounce in terms of mass > since 1959, still consistently calls them weights. "Weight" in this context means "mass", as Gene Nygaard will materialize and point out if I don't.
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Glenn Knickerbocker - 06 Jan 2009 13:17 GMT >> but US Title 15, while it defines the pound and ounce in terms of mass >> since 1959, still consistently calls them weights. >"Weight" in this context means "mass" It also uses the term "pounds per square inch" as a unit of pressure in sections 717z and 3301 (and until 1996 used it as a unit of tensile strength in section 5402). It does not say "pounds force per square inch."
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Hatunen - 06 Jan 2009 19:56 GMT >>> but US Title 15, while it defines the pound and ounce in terms of mass >>> since 1959, still consistently calls them weights. [quoted text clipped - 4 lines] >strength in section 5402). It does not say "pounds force per square >inch." My left rear tire recently needed 6 psi added to it, but I was unable to push six pounds mass into the tiny little valve stem.
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Roland Hutchinson - 06 Jan 2009 21:49 GMT >>>> but US Title 15, while it defines the pound and ounce in terms of mass >>>> since 1959, still consistently calls them weights. [quoted text clipped - 7 lines] > My left rear tire recently needed 6 psi added to it, but I was > unable to push six pounds mass into the tiny little valve stem. You silly, silly person! That little opening can't be more than a tenth of a square inch in area: you were clearly meant to push only 9 oz 9 19/32 dr (avoirdupois) of mass into it.
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Hatunen - 06 Jan 2009 22:44 GMT >>>>> but US Title 15, while it defines the pound and ounce in terms of mass >>>>> since 1959, still consistently calls them weights. [quoted text clipped - 11 lines] >square inch in area: you were clearly meant to push only 9 oz 9 19/32 dr >(avoirdupois) of mass into it. I think you meant "tenth of an inch square", which is even worse.
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Roland Hutchinson - 06 Jan 2009 23:24 GMT >>>>>> but US Title 15, while it defines the pound and ounce in terms of >>>>>> mass since 1959, still consistently calls them weights. [quoted text clipped - 13 lines] > > I think you meant "tenth of an inch square", which is even worse. I meant what I wrote, but I might have been off by an order of magnitude in my estimate.
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Mark Brader - 07 Jan 2009 09:04 GMT Glenn Knickerbocker:
> It also uses the term "pounds per square inch" as a unit of pressure in > sections 717z and 3301 (and until 1996 used it as a unit of tensile > strength in section 5402). It does not say "pounds force per square > inch." Hah, good point! Thanks.
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J. J. Lodder - 07 Jan 2009 10:32 GMT > Glenn Knickerbocker: > > It also uses the term "pounds per square inch" as a unit of pressure in [quoted text clipped - 3 lines] > > Hah, good point! Thanks. Maybe not. I guess 'psi' should be read as one unit, of pressure, and that it is defined as so many (kilo)Pascal,
Jan
Hatunen - 07 Jan 2009 17:29 GMT >> Glenn Knickerbocker: >> > It also uses the term "pounds per square inch" as a unit of pressure in [quoted text clipped - 7 lines] >I guess 'psi' should be read as one unit, of pressure, >and that it is defined as so many (kilo)Pascal, When working engineering problems treating psi as a single unit could become a problem. Pounds per square inch is written as lb/in*2 and in a typical problem the individual units might be cancelled. In fact, pound might be expanded to slug/sec*2 so that the units can be manipulated. Dimensional analysis can be an important process in working engineering and scientific problems.
For instance, to calculate the total force on an area of one square foot (144 in*2) by a 6 psi pressure might be written:
F = P x A
where
P = pressure in lb/in*2 A = area in in*2
F = 6 lb/in*2 x 144 in*2
F = 864 lb/in*2 in*2
Cancelling the in*2 in the numerator and denominator
F = 864 lb
(pound force, not pound mass)
This is a fairy simple problem, but in the USA material stress is still stated in psi or kpsi and more complicated problems can arise.
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John Holmes - 28 Dec 2008 08:39 GMT >> In the early 1960s my father was a visiting examiner for the >> University of London overseeing degree-level physics exams at a [quoted text clipped - 12 lines] > > Isn't weight measured in n? No, g is the weight divided by the mass. It has the dimensions of acceleration. It can vary quite a bit depending where you are on the globe and according to the local topography and the density of the rocks beneath your feet.
Perhaps you are getting confused with capital G or gamma, which is a constant everywhere, 6.670 x 10 ^-11 newton.m^2.kg^-2. That's the constant in Newton's Law of Gravitation.
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Chuck Riggs - 28 Dec 2008 10:37 GMT >>In the early 1960s my father was a visiting examiner for the University of >>London overseeing degree-level physics exams at a college in West Africa. [quoted text clipped - 10 lines] > >Isn't weight measured in n? Newtons are now abbreviated to N, I believe.
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Regards,
Chuck Riggs Near Dublin, Ireland
Garrett Wollman - 22 Dec 2008 16:58 GMT >I've always suspected that the reason for the US Gallon being 20% less >than the Imperial Gallon is due to some unscrupulous early settlers >started selling short-measure to the local inhabitants. Am I just being >cynical? The Imperial gallon was established more than two decades after the Treaty of Paris 1783.
Both U.S. customary gallons are the units which were in common use for their respective measures throughout the British Empire prior to the establishment of Imperial measure.
-GAWollman
 Signature Garrett A. Wollman | The real tragedy of human existence is not that we are wollman@csail.mit.edu| nasty by nature, but that a cruel structural asymmetry Opinions not those | grants to rare events of meanness such power to shape of MIT or CSAIL. | our history. - S.J. Gould, Ten Thousand Acts of Kindness
John Kane - 03 Jan 2009 17:36 GMT > On Sat, 20 Dec 2008 11:46:28 -0500, Robert Lieblich > [quoted text clipped - 11 lines] > > Unfortunately, of course, it's not the same gallon. I just noticed some food jugs, presumably imported from the USA have the meausurement 3.7l on them.
And I think butter is still sold in 454gm blocks.
However Imperial measures seem to be gradually disappearing here.
John Kane Kingston ON Canada.
Hatunen - 03 Jan 2009 21:49 GMT >> On Sat, 20 Dec 2008 11:46:28 -0500, Robert Lieblich >> [quoted text clipped - 14 lines] >I just noticed some food jugs, presumably imported from the USA have >the meausurement 3.7l on them. That's odd. The American gallon is 3.785 liters, so I'm not certain just what those jugs might be.
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R H Draney - 17 Dec 2008 01:57 GMT Mark Brader filted:
>In the US it is customary to measure the fuel efficiency of a car in >units of miles per (US) gallon or MPG. And here in Canada when I was [quoted text clipped - 14 lines] >did people ever use kilometers per liter (km/L) in Canada, Britain, >or other countries, or do they now? I remember a few years ago realizing that the units used for fuel consumption are effectively units of area...the accompanying gedankenexperiment had you imagining a car with no storage tank, but a suction hose dangling into a sea of fuel through which you drove; the rate of consumption was equal to the area of that hose's cross-section....r
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J. J. Lodder - 17 Dec 2008 11:32 GMT > Mark Brader filted: > > [quoted text clipped - 22 lines] > suction hose dangling into a sea of fuel through which you drove; the rate > of consumption was equal to the area of that hose's cross-section....r In the SI simplifications like these are not recommended, and may be considered to be an error,
Jan
Athel Cornish-Bowden - 17 Dec 2008 15:50 GMT >> [ ... ]
>> I remember a few years ago realizing that the units used for fuel >> consumption are effectively units of area...the accompanying [quoted text clipped - 4 lines] > In the SI simplifications like these are not recommended, > and may be considered to be an error, Could you expand?
There can surely be no doubt that, say, 5 litres per 100 km is an area, so what harm comes from asking what area it corresponds to?
Someone pointed out to me around 20 years ago that it was an area, and I initially had difficulty in visualizing what area it was, mainly because I was thinking in terms of a large area. Once I worked out how big it was, and realized that it was a very small area, there was no difficulty in arriving at the same conclusion as Mr Draney. (Except that maybe "hose" is the right word for high-consumption vehicles -- I think of it more like a tube of internal diameter about 3 mm.)
 Signature athel
Paul Wolff - 17 Dec 2008 17:22 GMT >On 2008-12-17 12:32:59 +0100, nospam@de-ster.demon.nl (J. J. Lodder) said: >> [quoted text clipped - 3 lines] >>> suction hose dangling into a sea of fuel through which you drove; the rate >>> of consumption was equal to the area of that hose's cross-section....r
>> In the SI simplifications like these are not recommended, >> and may be considered to be an error, [quoted text clipped - 11 lines] >that maybe "hose" is the right word for high-consumption vehicles -- I >think of it more like a tube of internal diameter about 3 mm.) It helps to state that, instead of just dangling, the mouth of the tube faces the direction of travel. Then the idea that the volume of fuel consumed equals the tube area times the distance travelled comes alive.
 Signature Paul
Prai Jei - 17 Dec 2008 19:14 GMT Paul Wolff set the following eddies spiralling through the space-time continuum:
>>On 2008-12-17 12:32:59 +0100, nospam@de-ster.demon.nl (J. J. Lodder) said: >>> [quoted text clipped - 24 lines] > faces the direction of travel. Then the idea that the volume of fuel > consumed equals the tube area times the distance travelled comes alive. British steam locomotives (possibly other countries also) used to be able to scoop up water from tanks laid along the tracks in the manner described. Not continuously of course (gradients would cause a bit of a problem) but they were able to top up their tanks without having to stop.
While I can visualise combustible fuel being supplied in this way, all elf'n'safety busybodies have to be banished from said visualisation.
The size of the typical fuel consumption figure expressed in SI units (0.000 000 08 m²) is the reason for the non-SI unit of l/100km being chosen for popular usage. The cubic metre is a very large volume of fuel (1000 litres, 220 Imperial gallons, 275 US gallons) while the metre is a very small distance to travel. To bring the figure into the easily visualisable "single integer digit" range we have to multiply it by eight powers of 10. Three come from using the litre as the unit volume of fuel, the remaining five from using 100km as the unit of distance.
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Mark Brader - 17 Dec 2008 19:30 GMT > British steam locomotives (possibly other countries also) used to be able to > scoop up water from tanks laid along the tracks in the manner described. > Not continuously of course (gradients would cause a bit of a problem) but > they were able to top up their tanks without having to stop. As it happens, this same connection was made recently in another newsgroup I read. This was then posted:
| My recollection of the main line watering troughs in the UK was | that they were a mile or so long. Mark will be along with the | right figure soon. And I responded as follows (copyedited for reposting):
Sorry, but I must confess to having no data on the typical dimensions of British railways' water troughs.
I do know that the technique was invented by John Ramsbottom for the London & North Western Railway and first used in 1860 on their line along the north coast of Wales, at a point between Colwyn Bay and Conway (now spelled Conwy); and that when this was being planned, the railway's Works Committee was asked to approve the relaying of half a mile of track. So perhaps that was the length of that original installation. The troughs were moved from there in 1871 to a position farther west, near Aber, but it is not clear why.
In other sources I find that water troughs were typically installed every 30 miles along British main lines, that there were 141 of them altogether, and that some were supplied with steam heat to keep them from freezing. Another L&NWR line had its only water troughs inside a tunnel (Standedge Tunnel, a triple bore over 3 miles long, 15 miles northeast of Manchester) because there was no other level track on that route.
In the days of steam locomotives, passenger trains were heated by steam from the boiler. When diesel and electric trains took over, boiler cars were carried for heating purposes until newer passenger rolling stock was obtained. In Britain, some water troughs were retained for a while for the purpose of refilling these heating boilers. North American railways also used the boiler cars but I don't know if any of them used water troughs to refill them (I suspect not -- they probably had larger water tanks here).
As to mountain railways, it says here that the highest-elevation installation of water troughs *in the world* was at Garsdale in northern England, on the Midland Railway's Settle and Carlisle Line. The elevation was only 1,100 feet -- high for British railways but tiny in comparison with those in the Andes, the Alps, or the Rockies.
(27 miles away, the L&NWR's west coast main line had water troughs just above sea level.)
(For those more familiar with the post-Grouping railways: both the Midland and the L&NWR became part of the London, Midland & Scottish.)
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R H Draney - 17 Dec 2008 19:42 GMT Prai Jei filted:
>Paul Wolff set the following eddies spiralling through the space-time >continuum: [quoted text clipped - 18 lines] >While I can visualise combustible fuel being supplied in this way, all >elf'n'safety busybodies have to be banished from said visualisation. I recall a science-fiction short story called "Light A Match" in which a spaceship was supposed to use this method for propulsion...they'd do some kind of hyperspace hop, then scoop up whatever matter was around to burn in their reactor as they coasted to the nearest settlement...in the story, an inept pilot had made a jump into the middle of a nebula rich in unsuitable organic compounds (it would clog the scoops, or wouldn't react, or something) and they had to figure out how to get into clear space again before life-support systems began failing....
The solution, as telegraphed by the title, was to combust the organics in a much older manner as a stopgap fuel source....r
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J. J. Lodder - 17 Dec 2008 22:58 GMT > Prai Jei filted:
> >British steam locomotives (possibly other countries also) used to be able to > >scoop up water from tanks laid along the tracks in the manner described. [quoted text clipped - 15 lines] > The solution, as telegraphed by the title, was to combust the organics in > a much older manner as a stopgap fuel source....r Mr Bussard did scoop up the fuel for his fusion ram jet on the way. He needed many sq km of collectin area though, (and the thing didn't work anyway)
Jan
J. J. Lodder - 17 Dec 2008 22:58 GMT > Paul Wolff set the following eddies spiralling through the space-time > continuum: [quoted text clipped - 35 lines] > While I can visualise combustible fuel being supplied in this way, all > elf'n'safety busybodies have to be banished from said visualisation. Jet fighters do it routinely,
Jan
R H Draney - 18 Dec 2008 00:52 GMT J. J. Lodder filted:
>> British steam locomotives (possibly other countries also) used to be able to >> scoop up water from tanks laid along the tracks in the manner described. [quoted text clipped - 5 lines] > >Jet fighters do it routinely, Worst.
Bumper sticker.
Ever.
....r
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Mike Barnes - 17 Dec 2008 17:38 GMT In alt.usage.english, Athel Cornish-Bowden wrote:
>>> [ ... ] > [quoted text clipped - 10 lines] >There can surely be no doubt that, say, 5 litres per 100 km is an area, >so what harm comes from asking what area it corresponds to? None, I would say, but harm would come from habitually expressing fuel consumption as an area rather than the way everyone else does it. Simplifying units doesn't necessarily make the units simpler to use.
If you Google "30 mpg in square mm" the answer comes back "0.094160351". This is the area you could theoretically scoop up to keep your engine going. Alternatively it's the gauge of string 30 miles of which would fill a gallon container.
I assume those are US gallons. The approximate metric equivalent is 10 L/100km which is 0.1 sq mm.
 Signature Mike Barnes Cheshire, England
J. J. Lodder - 17 Dec 2008 22:58 GMT > >> [ ... ] > [quoted text clipped - 8 lines] > > Could you expand? In the SI you can in principle multiply out all units to m^... kg^... s^... A^... Or you can combine some into Newton, Joule, etc. Some judgement is needed here, no automatic recipe exists. The classic example is that torques should be given in Nm, not in Joule, even though a Joule is defined as a Newton-meter.
> There can surely be no doubt that, say, 5 litres per 100 km is an area, > so what harm comes from asking what area it corresponds to? Sure, good question. (even though the answer isn't very useful) Don't express fuel consumption in mm squared though.
Jan
Athel Cornish-Bowden - 19 Dec 2008 08:06 GMT >>>> [ ... ] >> [quoted text clipped - 22 lines] > (even though the answer isn't very useful) > Don't express fuel consumption in mm squared though. OK, I don't, but it seems to me that there is a parallel example in the use of ohm cm to express resistivity. I found it very hard to visualize what this actually meant until I "translated" it into ohm cm^2 per cm. But the unit actually used is ohm cm (or was when I learned physics, many moons ago in pre-SI days) , not ohm cm^2 per cm.
> Jan
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J. J. Lodder - 20 Dec 2008 11:42 GMT > >>>> [ ... ] > >> [quoted text clipped - 29 lines] > But the unit actually used is ohm cm (or was when I learned physics, > many moons ago in pre-SI days) , not ohm cm^2 per cm. There is indeed an element of convention in it. There are good reasons for the difference though: for a piece of copper to be measured for resistance all dimensions are measured as length. In the case of fuel consumption the amount of fuel is measured as a volume, not as a product of three lengths.
And in fact, in the olden days the liter was a separate unit in the metric system. Due to inaccuracies in the original measurements the liter did not exactly equal the dm^3. (since redefined)
So I thend to think there is good reason for custom as it is,
Jan
PS For comparison: In the olden days it was customary to give engine volume in cm^3, not in litres, for it was actually measured as bore times stroke, not as a volume.
John Varela - 20 Dec 2008 18:05 GMT > In the case of fuel consumption the amount of fuel > is measured as a volume, not as a product of three lengths. Isn't that a distinction without a difference?
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Hatunen - 21 Dec 2008 20:54 GMT >> In the case of fuel consumption the amount of fuel >> is measured as a volume, not as a product of three lengths. > >Isn't that a distinction without a difference? Pretty much, especially since the liter is a unit with a bit of a cloud hanging over it, and SI recommends it not be used with something like cubic decimeter used instead. Up until the adoption of the new, improved metric system a few decades ago, the milliliter and the cubic centimeter were slightly different, a fact which made a good bar bet back then.
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Mark Brader - 21 Dec 2008 21:38 GMT Dave Hatunen:
> ... the liter is a unit with a bit of a cloud hanging over it, It's a non-SI unit accepted for use with the SI, as are things like hours and degrees (the kind you measure angles with).
> and SI recommends it not be used with > something like cubic decimeter used instead. That only applies when used "to give the results of high-accuracy volume measurements", and the reason is that...
> Up until the > adoption of the new, improved metric system a few decades ago, > the milliliter and the cubic centimeter were slightly different, > a fact which made a good bar bet back then.  Signature Mark Brader, Toronto, msb@vex.net A century from now people will salute Cole Porter, Lerner and Lowe, Rodgers and Hammerstein, and Andrew Lloyd Webber, all in one basket. I wonder how Bach would have felt to know that the bizarre and futuristic music of Beethoven and Brahms would be lumped in with his? -- Guy Steele
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Spehro Pefhany - 03 Jan 2009 15:02 GMT >Mark Brader filted: >> [quoted text clipped - 22 lines] >fuel through which you drove; the rate of consumption was equal to the area of >that hose's cross-section....r I think you mean a pickup tube sticking straight out into the direction of motion, like a Pitot tube, in the sea of fuel.
Google will do that conversion without breaking a sweat. For example:
Google: "0.08 mm^2 in miles per US gallon" (or " per Imperial gallon", if you prefer)
You can easily do the conversion from mm^2 to liters/100km by moving the decimal a couple of places to the right (of course mm^2 = liters/km).
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Peter Duncanson (BrE) - 17 Dec 2008 01:59 GMT >In the US it is customary to measure the fuel efficiency of a car in >units of miles per (US) gallon or MPG. And here in Canada when I was [quoted text clipped - 9 lines] >father already, but he doesn't remember the subject coming up at all >before we moved to Canada in 1957. In the UK fuel is sold by the litre but fuel efficiency has been and still is quoted in miles per (Imperial) gallon (mpg).
In general parlance "mpg" is called the "fuel consumption". Car makers seem to tend to call it "fuel economy".
 Signature Peter Duncanson, UK (in alt.usage.english)
DavidW - 17 Dec 2008 02:06 GMT > In the UK fuel is sold by the litre but fuel efficiency has been and > still is quoted in miles per (Imperial) gallon (mpg). > > In general parlance "mpg" is called the "fuel consumption". > Car makers seem to tend to call it "fuel economy". I guess they don't want people to think of cars as consuming anything.
Roland Hutchinson - 17 Dec 2008 14:41 GMT >> In the UK fuel is sold by the litre but fuel efficiency has been and >> still is quoted in miles per (Imperial) gallon (mpg). [quoted text clipped - 3 lines] > > I guess they don't want people to think of cars as consuming anything. I think of mpg as "mileage". I think of l/100 km as "fuel consumption".
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Errol - 17 Dec 2008 03:00 GMT <snip>
> What I want to know now is, how were these things measured in Britain > or other Commonwealth countries before the adoption of metric measure? [quoted text clipped - 6 lines] > did people ever use kilometers per liter (km/L) in Canada, Britain, > or other countries, or do they now? NZ used mpg until the road signage etc was changed ~1980, since when we have used l/100km. In my experience, people still don't think in the new terms.
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Fred - 17 Dec 2008 03:49 GMT On Dec 17, 1:18 pm, m...@vex.net (Mark Brader) wrote: <snip>
> What I want to know now is, how were these things measured in Britain > or other Commonwealth countries before the adoption of metric measure? [quoted text clipped - 6 lines] > did people ever use kilometers per liter (km/L) in Canada, Britain, > or other countries, or do they now? NZ used mpg until the road signage etc was changed ~1980, since when we have used l/100km. In my experience, people still don't think in the new terms.
Some might not, but many of the younger set have no idea what a gallon or a mile is.
DavidW - 17 Dec 2008 04:14 GMT > On Dec 17, 1:18 pm, m...@vex.net (Mark Brader) wrote: > <snip> [quoted text clipped - 16 lines] > Some might not, but many of the younger set have no idea what a gallon or a > mile is. You need this: http://home.in.tum.de/~jain/software/oe-quotefix/
DavidW - 17 Dec 2008 04:19 GMT >> On Dec 17, 1:18 pm, m...@vex.net (Mark Brader) wrote: >> <snip> [quoted text clipped - 19 lines] > You need this: > http://home.in.tum.de/~jain/software/oe-quotefix/ I recommend it in spite of the annoying possessive at the top of the page.
Garrett Wollman - 17 Dec 2008 03:41 GMT >Today our government has opted to have us use fuel consumption units, >the reciprocal of fuel efficiency, and specifically they have chosen >the non-SI metric unit of liters per hundred kilometers or L/100 km. When did that change happen? I remember seeing PSAs on the CBC in the early '80s, but ISTR that the official deprecation of Imperial measure was earlier (mid-1970s? I wasn't there to hear about it).
-GAWollman
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Mark Brader - 17 Dec 2008 06:42 GMT Mark Brader:
>> Today our government has opted to have us use fuel consumption units, >> the reciprocal of fuel efficiency, and specifically they have chosen >> the non-SI metric unit of liters per hundred kilometers or L/100 km. Garrett Wollman:
> When did that change happen? I remember seeing PSAs on the CBC in the > early '80s, but ISTR that the official deprecation of Imperial measure > was earlier (mid-1970s? I wasn't there to hear about it). I don't know when the unit of L/100 km was adopted. That's what I'm asking about. The push to convert to metric was in the early to mid 1970s, about the same as it was started but abandoned in the US.
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Lars Enderin - 17 Dec 2008 08:13 GMT > Mark Brader: >>> Today our government has opted to have us use fuel consumption units, [quoted text clipped - 9 lines] > asking about. The push to convert to metric was in the early to mid > 1970s, about the same as it was started but abandoned in the US. In Sweden, fuel consumption was always measured in litres per mile, but we have our own mile = 10 km. Thus the fuel consumption figures we speak of are usually 0.5 to 1.0, seldom above 1.0. My current car (a VW), however, shows L/100 km.
Mike Lyle - 18 Dec 2008 22:01 GMT [...]
> I don't know when the unit of L/100 km was adopted. That's what I'm > asking about. The push to convert to metric was in the early to mid > 1970s, about the same as it was started but abandoned in the US. It's worse in the UK. The Daily Express and its dickhead readers have got the process arrested half-way, as I think somebody's mentioned in the thread. 564 ml bottle of vinegar, anybody, to go with your litre bottle of oil? 800g loaf of bread to go with your 250g of butter?
But then I /am/ the bloke who was buying petrol in litres and calculating its "consumption" in miles per gallon until earlier this year, when I finally got round to modernising: I now work out my fuel use in miles per litre...
What I really want "them" to do is standardise shoe sizes. By which I don't mean "use the same numbers": I mean "use the same numbers to mean the same thing". Including within the same company.
 Signature Mike.
Mark Brader - 18 Dec 2008 22:10 GMT Mike Lyle:
> What I really want "them" to do is standardise shoe sizes. By which I > don't mean "use the same numbers": I mean "use the same numbers to mean > the same thing". Including within the same company. Hmm. If they don't, your shoe stores must not find the Brannock Device very useful. Or don't they use it?
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Mike Lyle - 18 Dec 2008 23:29 GMT > Mike Lyle: >> What I really want "them" to do is standardise shoe sizes. By which I [quoted text clipped - 3 lines] > Hmm. If they don't, your shoe stores must not find the Brannock > Device very useful. Or don't they use it? What, that thing you put your foot on and they slide the other bit of the thing onto your ingrown toenail?..<Ggls>... Yes, they do have them, but Charles F. laboured in vain as far as this sceptred isle is concerned.
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Fran Kemmish - 18 Dec 2008 23:33 GMT > Mike Lyle: >> What I really want "them" to do is standardise shoe sizes. By which I [quoted text clipped - 3 lines] > Hmm. If they don't, your shoe stores must not find the Brannock Device > very useful. Or don't they use it? Having spent many happy hours fitting dance shoes to young girls' feet, I can testify that the lack of standardisation of shoe sizes is an international phenomenon.
Fran
Robert Bannister - 18 Dec 2008 23:31 GMT > What I really want "them" to do is standardise shoe sizes. By which I > don't mean "use the same numbers": I mean "use the same numbers to mean > the same thing". Including within the same company. The same with clothing.
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Rob Bannister
R H Draney - 19 Dec 2008 02:18 GMT Robert Bannister filted:
>> What I really want "them" to do is standardise shoe sizes. By which I >> don't mean "use the same numbers": I mean "use the same numbers to mean >> the same thing". Including within the same company. > >The same with clothing. For nearly every item of clothing, the size [1] means *something*...for men's shirts, it's the collar circumference and sleeve length in inches...for trousers, the waist circumference and inseam length...men's hat sizes are the diameter of the form used to shame the crown; women's are the circumference of same...even shoes are supposedly measured in barleycorns, defined as coming three to the inch, with a non-zero starting point....
Women's dress sizes, however, defy any sort of reason...not only does a size eight not measure eight of any known unit in any known direction, an eight is not twice as big as a four...nor is an eight larger than a six by the same amount (relative or absolute) that a four is greater than a two....
Bring reason and order to women's dress sizes, and the world will beat a path to your door (and then you're done for)....r
[1] in the US...other realms may vary
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Wood Avens - 19 Dec 2008 10:24 GMT >Women's dress sizes, however, defy any sort of reason...not only does a size >eight not measure eight of any known unit in any known direction, an eight is >not twice as big as a four...nor is an eight larger than a six by the same >amount (relative or absolute) that a four is greater than a two.... The dress industry, at least the one here in the UK, periodically changes the standard (such as it is), as well. My, hmm, measurements have stayed exactly the same for the past 40 years. In that time, though, my dress size has diminished from a UK 12 to a UK 8.
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Roland Hutchinson - 19 Dec 2008 23:42 GMT >>Women's dress sizes, however, defy any sort of reason...not only does a >>size eight not measure eight of any known unit in any known direction, an [quoted text clipped - 6 lines] > have stayed exactly the same for the past 40 years. In that time, > though, my dress size has diminished from a UK 12 to a UK 8. It's the same in the US, and additionally all of the dress manufacturers' sizes run larger than patterns, which have conserved the earlier standard sizes at least to a degree. (I.e. if you buy a size 8 pattern you will end up with a much smaller dress than if you buy a size 8 dress.) Or so I am told by she who knows. Can barely sew a straight seam myself. Maybe not even that.
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Adam Funk - 19 Dec 2008 13:24 GMT > [...] >> [quoted text clipped - 6 lines] > the thread. 564 ml bottle of vinegar, anybody, to go with your litre > bottle of oil? 800g loaf of bread to go with your 250g of butter? The expression is something like "should be dragged kicking and screaming into the 20th, never mind the 21st century".
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J. J. Lodder - 20 Dec 2008 13:32 GMT > > [...] > >> [quoted text clipped - 9 lines] > The expression is something like "should be dragged kicking and > screaming into the 20th, never mind the 21st century". Well, you should excuse them. In their mind they are still fighting the Napoleonic wars,
Jan
the Omrud - 20 Dec 2008 14:39 GMT >>> [...] >>>> I don't know when the unit of L/100 km was adopted. That's what I'm [quoted text clipped - 9 lines] > Well, you should excuse them. > In their mind they are still fighting the Napoleonic wars, No, that's the French. We've got to WWII.
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Adam Funk - 05 Jan 2009 19:27 GMT [metrication]
> It's worse in the UK. The Daily Express and its dickhead readers have > got the process arrested half-way, as I think somebody's mentioned in [quoted text clipped - 5 lines] > year, when I finally got round to modernising: I now work out my fuel > use in miles per litre... A handy guide has just appeared, but I don't think it's aimed at the Daily Express audience.
http://xkcd.com/526/
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Steve Hayes - 19 Dec 2008 02:01 GMT >I don't know when the unit of L/100 km was adopted. That's what I'm >asking about. The push to convert to metric was in the early to mid >1970s, about the same as it was started but abandoned in the US. In South Africa it was adopted in 1971-72, along with the rest of the metric stuff.
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Don Phillipson - 17 Dec 2008 14:14 GMT > >Today our government has opted to have us use fuel consumption units, > >the reciprocal of fuel efficiency, and specifically they have chosen [quoted text clipped - 3 lines] > early '80s, but ISTR that the official deprecation of Imperial measure > was earlier (mid-1970s? I wasn't there to hear about it). In Canada, Systeme Internationale weights and measures (the "metric system") were generally approved many decades ago, possibly before the Second World War, but became mandatory (for fuel at the pump, potatos by weight etc.) in the 1970s. At this period a government "Metric Commission" promoted and explained SI units (and former prime minister Diefenbaker was still alive to fulminate against their adoption.)
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HVS - 17 Dec 2008 14:53 GMT On 17 Dec 2008, Don Phillipson wrote
> In Canada, Systeme Internationale weights and measures (the > "metric system") were generally approved many decades ago, [quoted text clipped - 3 lines] > explained SI units (and former prime minister Diefenbaker was > still alive to fulminate against their adoption.) Not particularly for that reason -- and the mileage of others may vary a great deal -- but even as a young teenager I found that man one of the epitome of an objectionable and pompous a.s of a politician. (Yes, I was much more a fan of Pearson.)
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CDB - 17 Dec 2008 16:47 GMT [Dief the Chief]
> Not particularly for that reason -- and the mileage of others may > vary a great deal -- but even as a young teenager I found that man > one of the epitome of an objectionable and pompous a.s of a > politician. (Yes, I was much more a fan of Pearson.) Obmileage: My father had dealings with both of them in the course of his work. He admired Pearson greatly, but he also said that Diefenbaker was a quite different, and much better, man in person than his later public image would suggest.
Steve Hayes - 17 Dec 2008 06:12 GMT >What I want to know now is, how were these things measured in Britain >or other Commonwealth countries before the adoption of metric measure? >Was it miles per (Imperial) gallon or something else? I asked my >father already, but he doesn't remember the subject coming up at all >before we moved to Canada in 1957. In South Africa it was measured in miles per (imperial) gallon.
It was called "fuel consumption", but that was a misnomer, and someone suggested it should be called "specific range".
Now we do measure fuel consumption, in litres per hundred kilometres, though we have no agreement on whether to pronounce "kilometres" as "KILL o meters" or "kil-O-mittuz".
>And does anyone remember a metric measure other than L/100 km ever >being customary for this purpose where they lived? In particular, >did people ever use kilometers per liter (km/L) in Canada, Britain, >or other countries, or do they now?
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Roland Hutchinson - 17 Dec 2008 14:44 GMT >>What I want to know now is, how were these things measured in Britain >>or other Commonwealth countries before the adoption of metric measure? [quoted text clipped - 6 lines] > It was called "fuel consumption", but that was a misnomer, and someone > suggested it should be called "specific range". I love it! I may start using it over here -- adapted to US gallons, of course.
> Now we do measure fuel consumption, in litres per hundred kilometres, > though we have no agreement on whether to pronounce "kilometres" as "KILL > o meters" or "kil-O-mittuz".
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Mike Barnes - 17 Dec 2008 10:46 GMT In alt.usage.english, Mark Brader wrote:
>In the US it is customary to measure the fuel efficiency of a car in >units of miles per (US) gallon or MPG. And here in Canada when I was [quoted text clipped - 6 lines] >What I want to know now is, how were these things measured in Britain >or other Commonwealth countries before the adoption of metric measure? In Britain we have fuel dispensed by the litre but distances are still in miles and "fuel consumption" (actually fuel range) is still in miles per (Imperial) gallon. Many people will know that they use L/100km on the continent but few will have a feel for how that relates to mpg, except perhaps that it's the other way round.
What really gets me is journalists talking about fuel consumption and emissions levels as is they were unrelated features of a car's performance, sometimes marvelling at the fact that a manufacturer can reduce both simultaneously.
 Signature Mike Barnes Cheshire, England
J. J. Lodder - 17 Dec 2008 11:32 GMT > In the US it is customary to measure the fuel efficiency of a car in > units of miles per (US) gallon or MPG. And here in Canada when I was [quoted text clipped - 3 lines] > the reciprocal of fuel efficiency, and specifically they have chosen > the non-SI metric unit of liters per hundred kilometers or L/100 km. In the part of continental Europe I know about 'consumption' used to be given in the reciprocal unit, km/l. Sometime after the oil crisis people realised that this is not really a consumption, and that the figure mmay be misleading. So very graudually the km/l is being phased out and replaced by the l/100km.
As elsewhere, changes like this take generations before the old usage has died out.
Jan
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