## Standard units in America?

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Tass
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### Re: Standard units in America?

22/7 wrote:
Indon wrote:It strikes me as strange that many of the arguments for decimal measurements, such as ease of conversion, could readily be applied to establishing a decimal measurement of time. Yet, I'm pretty sure everywhere in the world still uses Seconds/Minutes/Hours with their 60-1 conversion ratios.

Edit: Not that I care. I have an equally poor grasp on the metric and standard measurement systems.
It's my understanding that a fair amount of work has been put into creating a metric system for time, and that it was largely unsuccessful.

I think a point is that hours, minutes and seconds have/had already won out. There is hardly anyone who uses any other system. For length and weigth and so on people were/are using a lot of different units, making the market open for new ones. Not so with the time.

No matter if you choose imperial, standart or metric you are going to have trouble with someone. Switching to newseconds is going to make problems with virtually everyone, where there were none before.

In the same way, english is a terrible international language, the grammar and spelling is highly irregular. But like it or not english has won. I am not going to learn Esperanto because noone else speaks it.

Solt
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### Re: Standard units in America?

Hmm. I stopped paying attention when people started talking about apples and kansas, but there seem to be new arguments now...

The Ethos: it's a good theory but it's wrong. You see this is the 21st century and we have these things called decimals. Even our rulers give readings in decimals now. So it's not really a problem. Yes, there's the occasional conversion because standard tools are marked in pretty fractions, but it's not really an issue. More often than not part dimensions are specified as, for example, 1.12 inches which is no different and no easier or harder to make than 2.84 cm. How do you deal with the fact that it's really 2.8448 cm? No differently: tolerance works the same way in all unit systems.

cspirou wrote:My view is that there should be a law mandating that everything should have metric and standard printed equal in size.

Oh yea, government is going to solve all our problems. Let's just make some new laws. Communist.
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produced a more reliable product. But sailors do
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Monty40xi
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### Re: Standard units in America?

Solt wrote:Hmm. I stopped paying attention when people started talking about apples and kansas, but there seem to be new arguments now...

The Ethos: it's a good theory but it's wrong. You see this is the 21st century and we have these things called decimals. Even our rulers give readings in decimals now. So it's not really a problem. Yes, there's the occasional conversion because standard tools are marked in pretty fractions, but it's not really an issue. More often than not part dimensions are specified as, for example, 1.12 inches which is no different and no easier or harder to make than 2.84 cm. How do you deal with the fact that it's really 2.8448 cm? No differently: tolerance works the same way in all unit systems.

Have you actually used inches-based automated manufacturing equipment? Tolerance is actually the problem. If you want a metric distance plus or minus a metric tolerance, you have to convert both numbers and round off (usually to the nearest .005" for distance and nearest .001" for tolerance where I work). The end result? A slightly different range of distances than you were aiming for. Your numbers say the part's going to come out correctly; the customer gets his calipers and finds out the real metric dimensions don't match. Your part is junk. You could bring down your tolerance range even tighter (if you've got good enough equipment to go tighter) but that's always more expensive. You make more money by sticking to jobs that actually call for inches in the first place, and thus the US system survives.
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22/7
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### Re: Standard units in America?

The exact same thing could be said of metric calibrated machinery in the US.

Of course, the machine shop I used had equipment that would run in either metric or standard and was at least 15-20 years old, so I'm not particularly familiar with there being an issue, but...
Totally not a hypothetical...

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Solt
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### Re: Standard units in America?

22/7 wrote:The exact same thing could be said of metric calibrated machinery in the US.

Of course, the machine shop I used had equipment that would run in either metric or standard and was at least 15-20 years old, so I'm not particularly familiar with there being an issue, but...

Yea... digital scales that can be switched with the press of a button and metric bits if needed.
"Welding was faster, cheaper and, in theory,

produced a more reliable product. But sailors do

not float on theory, and the welded tankers had a

most annoying habit of splitting in two."

-J.W. Morris

Seraph
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### Re: Standard units in America?

22/7 wrote:The exact same thing could be said of metric calibrated machinery in the US.

Of course, the machine shop I used had equipment that would run in either metric or standard and was at least 15-20 years old, so I'm not particularly familiar with there being an issue, but...

Did the equipment really run in both, or did it just have the ability to read units in both?
I've worked with several lathes that could read in both, but I never encountered one that could cut both metric and standard threads.

banjo
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### Re: Standard units in America?

American English has changed less since the US split from Britain....it is the British who decided to be "different".

Ex.

Tire is an older spelling than tyre, but both were used in the 15th and 16th centuries for a metal tire; tire became the settled spelling in the 17th century. In the UK, tyre was revived in the 19th century for pneumatic tyres, possibly because it was used in some patent documents, though many continued to use tire for the iron variety. The Times newspaper was still using tire as late as 1905.

from:

http://en.wikipedia.org/wiki/Tire

As for metric vs imperial, personally I think imperial is hard to kill because it is sized to fit humanity. An inch is about how long the segment of my thumb is, the foot about the length of my foot. A gallon of water is about what you need to drink in a day....etc.

As for all you Europeans, I have to admit I'm a complete dipshit, you never really changed to metric. I can attest to that after living there for a few years with a digital caliper....That is unless the 5.080 cm is a rational choice for pipe diameter. Or the 2.540 cm thick door. Or the 1.27 cm neck of a beer bottle....funny how a 225 g steak is nearly exactly 8 oz too....

As for me I use metric in all of my calculations but convert to imperial any time I want a sense of the actual size. And in aerospace engineering they invented a whole bunch of unit-less ratios, but I still had to learn how to work in both systems, and all their variations. Physics was a breeze being all in metric...with one consistent unit of force, that is not easily confused with a pseudo mass unit..... My "favorite" unit is my mom's. the nautical mile(close to one minute of longitude at the equator iirc), or even better a "data mile". I would gladly welcome a single consistent set of units, but there is not one set that is optimal for all cases.

I can't believe I signed up solely to be a dick?

Tee-hee-hee--couldn't resist.

Habz
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### Re: Standard units in America?

banjo wrote:As for all you European dipshits, you never really changed to metric. I can attest to that after living there for a few years with a digital caliper....That is unless the 5.080 cm is a rational choice for pipe diameter. Or the 2.540 cm thick door. Or the 1.27 cm neck of a beer bottle....funny how a 225 g steak is nearly exactly 8 oz too...

You must be the american dipshit then huh? I dunno where you've lived, but I've never seen any of those but 225g steaks. I've been working on construction sites, and all the pipes I've handled have been 10/20/50/100/150/etc. of diameter in mm's. Thickness of the doors in my apartment seem to be exactly 4 cm's... Ever occurred to you that the examples you provided may just be the odd import products from your side of the atlantic? I'm pretty confident it happens counter-wise too.

banjo wrote:I can't believe I signed up solely to make myself look like a douche.

Fix'd.

Grop
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### Re: Standard units in America?

banjo wrote:As for me I use metric in all of my calculations but convert to imperial any time I want a sense of the actual size.

This is only because you are used to it. If I have to describe something that is roughly one foot long, I think of it as roughly 30 cm. There is nothing hard about it if you are used to it (and on the opposite, I need converting if you express a length in segments of thumbs).

Edit: Wow, did you say somehing about apologizing?
Last edited by Grop on Fri Nov 28, 2008 8:37 pm UTC, edited 1 time in total.

banjo
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### Re: Standard units in America?

Habz wrote:You must be the american dipshit then huh?

Habz wrote:
banjo wrote:I can't believe I signed up solely to make myself look like a douche.

Fix'd.

Ad hominem attacks, always the sign of competent debater, and towering intellectual....(yes I see the irony)

Habz wrote:I dunno where you've lived, but I've never seen any of those but 225g steaks. I've been working on construction sites, and all the pipes I've handled have been 0.5/1.0/2.0/4.0/6.0/etc. of diameter in inches. Thickness of the doors in my apartment seem to be exactly 4 cm's... Ever occurred to you that the examples you provided may just be the odd import products from your side of the atlantic? I'm pretty confident it happens counter-wise too.

Fixed. Next time use a caliper. Or perhaps they've switched over since my apartment had been built. It was probably built in the 60's by turks... The allies flattened the area...missing the V2's just down the road.

I was based in Den Haag, but I traveled all over. I saw 225g steaks in every place I saw one on a menu. Incidentally, beef is not recommended to any americans traveling in Europe, it is generally gamey and you'll be lucky to get them to cook it sufficiently(except in the UK, where they burn it). Also avoid salsa, too often it is ketchup....or something. That being said I miss the cheap, good beer and wine and awesome cheese etc, and the fritezaus and stroopwafels... I threw out 3 bottles of beer at my friends house when I first got back. I thought they were skunked. I still marvel how alcohol was always cheaper than both water and soda. My co-workers and I became convinced most europeans must live out their days in constant intoxicated dehydration. I think I'd trade that for the decent beer.

Actually the stuff in the former soviet union countries was really in metric...now that you mention it, which might explain why you, presumably in Finland, are so irate. Next time you're at a bar though, take a caliper and measure the inside diameter of the bottle you're drinking, I'll bet it is a round fraction of inches.

Or check out the recipes....rice for instance requires 240 ml of water per 225g of rice. I can't tell you how relieved I was when I realized that was 1 cup of water....etc.

Grop wrote:This is only because you are used to it. If I have to describe something that is roughly one foot long, I think of it as roughly 30 cm. There is nothing hard about it if you are used to it (and on the opposite, I need converting if you express a length in segments of thumbs).

Possibly, but then nautical miles will always make sense if you spend any amount of time looking at a chart. Unless of course you are in the infantry, but then again your world consists of this hill and the next.....so.... I guess you missed my point that the units you use must make sense for the work you're doing. For me conceptualizing size, in relation to myself, it makes sense to use feet inches and gallons. When I'm doing astronomy, lightyears. Or orbital mechanics, canonical units based on the Earth frame....usually. Relativity, I prefer units where c = 1. All the programs I write however are in SI, because it's easier to keep the units straight.

I apologize for calling all europeans dipshits. It's only the preponderance that are, same as in the US. Most of you, like most USians, are provincial and in colloquial american, rednecks(or sheltered suburbanites). Unlike those dipshits in the US you claim to be enlightened(which is slightly better than being proud of your ignorance, like the american equivalent).

wst
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### Re: Standard units in America?

Habz wrote:
banjo wrote:I can't believe I signed up solely to be a douche.

Fix'd.

Fixed more properly.

A teaspoon holds 5 grams of sugar. A desert spoon holds 10. Makes the hell-up for all those door that aren't an even number of centimetres thick eh banjo?
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gmalivuk
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### Re: Standard units in America?

banjo wrote:Ad hominem attacks, always the sign of competent debater, and towering intellectual.
I apologize for calling all europeans dipshits. It's only the preponderance that are, same as in the US. Most of you, like most USians, are provincial and in colloquial american, rednecks(or sheltered suburbanites). Unlike those dipshits in the US you claim to be enlightened(which is slightly better than being proud of your ignorance, like the american equivalent).

You're the one using ad hominem attacks. (The edit you complained about is where you called everyone punks, which is also ad hominem.)

Stop it or leave.
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### Re: Standard units in America?

banjo wrote:
Habz wrote:You must be the american dipshit then huh?

Habz wrote:
banjo wrote:I can't believe I signed up solely to make myself look like a douche.

Fix'd.

Ad hominem attacks, always the sign of competent debater, and towering intellectual....(yes I see the irony)

Just to show how competent of a debater I am, I will pedantically note that insulting someone is not an ad hominem attack. Ad hominem is when you use an irrelevant personal detail to argue against the person and pretend that you are arguing against the point. Insulting someone is just fun.

For an example:
You talk funny, so you're wrong.

This is committing the ad hominem fallacy.
You're wrong, and you talk funny. Also you're a douche.

This is just being insulting. No fallacy is being committed.

My towering intellect is towering.
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wst
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### Re: Standard units in America?

gmalivuk wrote:
banjo wrote:Ad hominem attacks, always the sign of competent debater, and towering intellectual.
I apologize for calling all europeans dipshits. It's only the preponderance that are, same as in the US. Most of you, like most USians, are provincial and in colloquial american, rednecks(or sheltered suburbanites). Unlike those dipshits in the US you claim to be enlightened(which is slightly better than being proud of your ignorance, like the american equivalent).

You're the one using ad hominem attacks. (The edit you complained about is where you called everyone punks, which is also ad hominem.)
Hey, hey, who said punk is a bad thing? I think you just ad hominem attacked punks (I've never used that phrase before, so the sytax may be screwy).

Idea: I think I know why Europe hasn't completly gone to using round metric figure dimensions. Door and shit are old, and were probably built in inches for ages. Doorways around Europe have a 1 inch recess for the door. I'm guessing it would be impossible to implement a Europe-wide conversion to 10 or 20 mm deep doorway recesses. So we just make the doors fit the holes. In this case, a 25.4mm hole.
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### Re: Standard units in America?

I'm not sure that standard really does actually apply to body measurements--particularly because people's bodies are all different sizes. That might work for approximation--but that's really not going to help much. For the record--my foot is no where near a foot in length.

That said--any unit of measurement, particularly those that are frequently used, can become natural and intuitive. In terms of industrial machines and products--whether a something is a bizarre decimal in inches or centimetres really isn't the greatest concern. What I know from friends who do Mech Eng is that school makes them do metric and about half of machine shops use standard and that in and of itself is frustrating (particularly because we use metric here in school so it's a whole learning curve of fraction gibberish to the uninitiated).

I really don't think that inherently one is better than the other--though metric makes a lot more sense to me personally. I do think that a universal standard would be fantastic and that rather than mandating it to happen immediately, a slow change in that direction when new machine parts are purchased could probably do it.

But then robertson screws--which are so much easier and less likely to wear out--don't ever get used for anything. Old habits die hard.
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ks_physicist
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### Re: Standard units in America?

The problem I see is that, while schools usually teach metric, all of the 'common' measurements are in Imperial/British.

So, you talk Meters and Kilograms in physics class, but when it "counts" you drive to practice in a car with a speedometer in MPH, weigh in on a scale that measures pounds, and you play football on a 100 yard long field.

When we DO have a "common" measurement in metric, people can get it just fine. Most people can conceptualize one or two liters, because we have soda sold in those quantities.

p.s.--I teach high school physics, and I'm baffled by the students who have had no intro to Metric. The middle school science teachers said they had the same problem, and traced it back to elementary teachers who said that they do a day of Metric in their 'science' lessons, but that it is just "too hard to understand." Too hard? What the heck?

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### Re: Standard units in America?

cspirou wrote:My view is that there should be a law mandating that everything should have metric and standard printed equal in size. Then over the years make standard smaller and smaller in print. It's true many people won't adapt but that's mainly a generational thing. We should definitely be able to shift within one generation.

I don't think just making the metric measurement more visible is going to help. The key is making it more convenient. If Europe decided to change over to american units, I wouldn't go out to buy 2.208 lbs of flour. I'd go and buy 1kg, no matter how small the print is. If, on the other hand, the packet was marked as '2lbs/0.906kg', I would be much more inclined to start thinking in pounds. Of course changing the packing size for everything is much more expensive than simply printing another number on the label, but it's probably the only way to make people want to change.

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### Re: Standard units in America?

It really isn't that expensive--companies change packing size all the time--usually to slightly smaller amounts when they jack up the price per unit...
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### Re: Standard units in America?

In fact, this would create a once-in-a-lifetime opportunity to reduce quantity while possibly *increasing* prices, as they drop down to the nearest round metric number and complain about the costs of changing all the presses in their factory.
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### Re: Standard units in America?

Well, there are some standard units which are just silly.
For instance, why not measure stoves in terms of Watts? BTU/h is pure silliness, and I don't think many people have any real idea of how much heat 2000BTU is. On the other hand, Watts is a nice unit, and is both easy to understand and to compare. If, for instance, someone talks about 500W heat, I know intuitively how much hotness/second that is. Same goes with Watts>horsepower, Watts>lumens.

Seraph
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### Re: Standard units in America?

Mr. Beck wrote:Well, there are some standard units which are just silly.
For instance, why not measure stoves in terms of Watts? BTU/h is pure silliness, and I don't think many people have any real idea of how much heat 2000BTU is. On the other hand, Watts is a nice unit, and is both easy to understand and to compare. If, for instance, someone talks about 500W heat, I know intuitively how much hotness/second that is. Same goes with Watts>horsepower, Watts>lumens.

I'm not sure someone who doesn't know that Watts and Lumens measure very different things is the person to be taking advice from when it comes to picking units. Lumens measure luminous flux and are defined in relation to candella (one of the base SI units). Watts are a measure of radient flux.

As for your BTU comment: If a population that has had to buy furnaces, air conditioners, water heaters, etc. in BTU's doesn't understand the unit at this point, what makes you think that relabing from 2000 BTU to 2 MJ will make things any clearer to them? The BTU is nice in one respect in that 1 cubic foot of natural gas is about 1 MBTU.

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### Re: Standard units in America?

I know the difference between Lumens and Watts, thank you very much. I prefer Watts due to the fact that it makes doing things like measuring efficiency much easier ...OK, I'm an idiot. It makes no sense to count the IR emitted by a lightbulb on the side of the tin, and any case where human perception is unimportant is using watts already.

speraph wrote:What makes you think that relabing from 2000 BTU to 2 MJ will make things any clearer to them?
Wikipedia wrote:1 BTU= 1055.05585262 J
Sorry, but the conversion is an actual conversion. You can't just multiply by a power of ten.

Seraph wrote:The BTU is nice in one respect in that 1 cubic foot of natural gas is about 1 MBTU.
This brings up another thing: 1MBTU=!= 1,000,000BTU. Yeah, the rate above is handy, but having confusing prefixes negates any vale that this holds.

My statement on Horsepower still stands.

Grop
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### Re: Standard units in America?

Regarding watts/BTU, I don't expect most people to really know what they are. I would expect the average person, with no science or technical backgroung, to only view them as magic numbers, like, bigger magic number is awesomer and more expensive.

I expect such units, hardly intuitive to the public, may easily be changed without cultural difficulty.

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### Re: Standard units in America?

Mr. Beck wrote:This brings up another thing: 1MBTU=!= 1,000,000BTU.

What now? If 1 Million British Thermal Units is not 1,000,000 BTU, what, then, is it exactly?

I don't have a problem with people who advocate for the US going metric, but it does bother me when the arguing is being done by people who don't actually even understand what the hell they're arguing against...
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### Re: Standard units in America?

brodieboy255 wrote:I've grown up in metric, yet I still inexplicably approximate things in imperial units on a daily basis, namely inches and feet

I'm just the opposite. I grew up with Imperial units, but I use exclusively metric at work. Metric is so much easier to use, it's just been slowly creeping in over the years. Volume, mass, and temperature are all metric in my mind now. Makes cooking difficult; I can instantly picture 100mL, but 1c? Not a clue. 40 is a sweltering day, and I have to to division in my head to figure out how much something weighs when I lift it.

Only thing left is long distances. Short distances I estimate in cm now; moderate distances sometimes in meters, sometimes in feet; but it's been that way all my life as a result of competitive swimming as a kid. But I still can't imagine 100km on a map without calculating it.

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### Re: Standard units in America?

I use metric for everything but height. Though I do know my height in centimetres--I find that people don't know what it means without the feet and inches.
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wst
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### Re: Standard units in America?

Rinsaikeru wrote:I use metric for everything but height. Though I do know my height in centimetres--I find that people don't know what it means without the feet and inches.
A few months (like, February) I fugred out my height in cms and also in imperial. PRoblem with height and metric is, I have grown another 10 or so cms since February. Also, I have ~1cm of hair, but that varies, etc...
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### Re: Standard units in America?

i've never quite understood why Americans use two different units two express their height. Feet and inches. I can understand using either unit, but both at once? That's so confusing. Why express your height as 6 feet 2 inches and not 74 inches or 6.17 feet? Much easier!

I've actually met Americans who couldn't do something as simple as calculating the length difference between two people, because they couldn't do the conversion from feet to inches. Damn.
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### Re: Standard units in America?

I don't see the point of calculating it all in inches (or even in centimetres). The human body is obviously large enough to be measured in feet or metres because it is generally longer than one of either. The larger units give you a ballpark where the smaller are for more specific things. When I think about height I can group people into about 5 feet, about 6 feet, shorter than 5 feet etc. The inches just make that clearer.

If you tell me someone is 150cm tall I don't really have the clearest understanding of what that looks like in centimetres, I'd convert to metres in my head so i could understand what you meant.
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### Re: Standard units in America?

I've seen acceleration measured in ft/s2 tons (lol) of times. They use it in engineering. They often use BTUs, hp, bbls, bpd, gpm, SCFD, etc. It's dumb from a scientific perspective, but as they've said it's expensive to switch, and it has the side benefit of teaching you to think of things as quantities independently of how they're measured, kind of like how learning multiple languages lets you think of concepts in and of themselves instead of as rigidly determined by the words that describe them.

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### Re: Standard units in America?

gmalivuk wrote:
Mr. Beck wrote:This brings up another thing: 1MBTU=!= 1,000,000BTU.
What now? If 1 Million British Thermal Units is not 1,000,000 BTU, what, then, is it exactly?
Wikipedia wrote:The unit MBTU was defined as one thousand BTU presumably from the Roman numeral system where "M" stands for one thousand (1,000). This is easily confused with the SI mega (M) prefix, which adds a factor of one million (1,000,000). To avoid confusion many companies and engineers use MMBTU to represent one million BTU. Alternatively a therm is used representing 100,000 or 105 BTU, and a quad as 1015 BTU.

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### Re: Standard units in America?

Okay, well the first several Google results from a search of MBTU describe it as a million BTU or as one decatherm (where a therm, as you say, is 105 BTU), so either it's changed meaning since it was originally defined (note the past tense in what you quoted), or else Wikipedia is simply wrong.
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jaap
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### Re: Standard units in America?

gmalivuk wrote:Okay, well the first several Google results from a search of MBTU describe it as a million BTU or as one decatherm (where a therm, as you say, is 105 BTU), so either it's changed meaning since it was originally defined (note the past tense in what you quoted), or else Wikipedia is simply wrong.

Other similar cases in the oil industry are MMSTB, which means a million standard barrels (or million stock-tank barrels) of oil, and MMft3 which is a million cubic feet of gas.

Carnildo
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### Re: Standard units in America?

Rinsaikeru wrote:It really isn't that expensive--companies change packing size all the time--usually to slightly smaller amounts when they jack up the price per unit...

A full conversion to metric is going to be bloody expensive. I used to work at a mechanical testing lab; here's some of what would be involved in coverting to metric:

Converting the 10-ton and 30-ton presses to output mechanical stress in kilograms rather than pounds would be easy: the actual measurement is in ohms, and the software is already able to convert that to metric units. The 120-ton press would be harder: it dates to 1943, and the analog-mechanical plotter still uses vacuum tubes. You'd need an electronics guy to open it up and rewire the gain circuitry with the new scaling factors. Estimated cost: \$1000 plus re-calibration for the 120-ton press, free for the others.

The extensometers for measuring mechanical strain are a different matter: they're built with half-inch, one-inch, and two-inch gage lengths, and it's physically impossible to change them. You need to replace all four. Estimated cost: \$50,000 for replacement and calibration.

But the presses are still built using US customary parts, and these break on a regular basis. What are you going to do twenty years down the road when one of the half-inch bolts holding the load cell down shears off, and nobody makes replacements any more? Replacing the 10-ton and 30-ton presses would run around a quarter-million dollars each; the 120-ton press would be close to half a million.

What about hardness testing? I don't know what the metric standard for hardness is, but I'm fairly sure that a machine for testing Rockwell hardness can't be converted: the different standards use fundamentally different techniques for measuring it. Four automated hardness testers at \$25,000 each: \$100,000; one elevated-temperature hardness tester and furnace: \$50,000; if the computerized microhardness tester (it does both Vickers and Brinell) needs replacing, \$100,000.

The fatigue lab has six axial fatigue testers, eight rotating-bending fatigue testers, and three low-cycle fatigue testers. Cycle counts are the same between customary and metric, but the stress loads aren't. Further, since almost all fatigue-testing work was done for US-based automobile manufacturers, the custom-designed control and data collection software can't handle metric: \$10,000 for new software, plus the cost of re-calibrating seventeen machines.

Replacement parts for the fatigue-testing machines would be even more critical. Since these machines are designed to see how fast parts wear out, they themselves wear out quickly: it's rare to have more that two-thirds of them up at any given time. Replacing the entire lab would probably run around \$1,000,000-\$2,000,000.

And then there are the miscellaneous bits: the gage-mark punches calibrated at half-inch, one-inch, and two-inch sizes, the calipers and micrometers that use inches, the threaded inserts for bolt testing, the end plugs for tensile testing of tubes, the calibrated five-pound sledgehammer for dealing with recalcitrant parts, and so on...

Jorpho
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### Re: Standard units in America?

gmalivuk wrote:Powers of two along with the occasional multiple of three are not that difficult to work with. The only real difficulty for mental math comes from the factor of 11 in 5280. (Owing to the fact that a rod is 16.5 feet and there are exactly 320 of those in a mile, with 4 in a chain, 10 chains in a furlong, and 8 furlongs in a mile.)
Seriously, what's up with that? Who the crap came up with 1760 yards per mile?! Factors of 12 I can understand, but 1760 !?

gmalivuk wrote:Old units of energy, for instance, told you exactly how much hotter a certain quantity of water would get if you added that much energy to them. (A calorie raises a gram of water 1 degree C, a BTU raises a pound of water 1 degree F.) Using SI units, you have to remember that the specific heat of water is about 4.18.
The utter meaninglessness of the Fahrenheit scale offends me too. So one end is a wildly inaccurate measurement of human body temperature, and the other end is a really cold temperature that Mr. Fahrenheit managed to come up with one day?

Carnildo
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### Re: Standard units in America?

Jorpho wrote:
gmalivuk wrote:Powers of two along with the occasional multiple of three are not that difficult to work with. The only real difficulty for mental math comes from the factor of 11 in 5280. (Owing to the fact that a rod is 16.5 feet and there are exactly 320 of those in a mile, with 4 in a chain, 10 chains in a furlong, and 8 furlongs in a mile.)
Seriously, what's up with that? Who the crap came up with 1760 yards per mile?! Factors of 12 I can understand, but 1760 !?

The mile started out as 1000 Roman double-step paces (thus the name). The Romans did most of the early road-building and surveying in Europe, so their mile stuck as a large unit of distance (give or take 10%), but at the short end, the pace was replaced by the English foot, with the resulting awkward conversion factor.

gmalivuk wrote:Old units of energy, for instance, told you exactly how much hotter a certain quantity of water would get if you added that much energy to them. (A calorie raises a gram of water 1 degree C, a BTU raises a pound of water 1 degree F.) Using SI units, you have to remember that the specific heat of water is about 4.18.
The utter meaninglessness of the Fahrenheit scale offends me too. So one end is a wildly inaccurate measurement of human body temperature, and the other end is a really cold temperature that Mr. Fahrenheit managed to come up with one day?

The degree F is actually a very useful unit for everyday human experience: 0F is about the coldest temperature someone in a temperate climate will experience in the typical year; 100F is the hottest. 10 degrees F is about the minimum change a person will notice.

Jorpho
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### Re: Standard units in America?

Carnildo wrote:The degree F is actually a very useful unit for everyday human experience: 0F is about the coldest temperature someone in a temperate climate will experience in the typical year; 100F is the hottest. 10 degrees F is about the minimum change a person will notice.
I would argue that it's much better to have a convenient value for the melting point of ice, since a temperature of 0F isn't likely to be experienced very often, depending on what sort of "temperate climate" (now there's an all-encompassing term) you live in. I might also dispute that 10F is the minimum change a person will notice. (It's pretty easy to notice a lot less than that, methinks.)

Sir_Elderberry
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### Re: Standard units in America?

Jorpho wrote:
Carnildo wrote:The degree F is actually a very useful unit for everyday human experience: 0F is about the coldest temperature someone in a temperate climate will experience in the typical year; 100F is the hottest. 10 degrees F is about the minimum change a person will notice.
I would argue that it's much better to have a convenient value for the melting point of ice, since a temperature of 0F isn't likely to be experienced very often, depending on what sort of "temperate climate" (now there's an all-encompassing term) you live in. I might also dispute that 10F is the minimum change a person will notice. (It's pretty easy to notice a lot less than that, methinks.)

I remember New Scientist once saying you could detect a fraction of a degree in change, subconsciously. The story was about people building a "haunted house" that worked through cues like infrasound, tiny changes in drafts and temperature, etc. I can't find a source to cite for this besides that.
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Carnildo
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### Re: Standard units in America?

Sir_Elderberry wrote:
Jorpho wrote:
Carnildo wrote:The degree F is actually a very useful unit for everyday human experience: 0F is about the coldest temperature someone in a temperate climate will experience in the typical year; 100F is the hottest. 10 degrees F is about the minimum change a person will notice.
I would argue that it's much better to have a convenient value for the melting point of ice, since a temperature of 0F isn't likely to be experienced very often, depending on what sort of "temperate climate" (now there's an all-encompassing term) you live in. I might also dispute that 10F is the minimum change a person will notice. (It's pretty easy to notice a lot less than that, methinks.)

I remember New Scientist once saying you could detect a fraction of a degree in change, subconsciously. The story was about people building a "haunted house" that worked through cues like infrasound, tiny changes in drafts and temperature, etc. I can't find a source to cite for this besides that.

You can detect smaller changes under the right circumstances, yes, but a gradual 10F change is about the point where you go "huh, it's gotten warmer in here".

Luthen
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### Re: Standard units in America?

It's all really irrelevance as people don't feel temperature. Our heat sensitive nerves are sensitive to how much heat is moving between us and what we're touching. Hence why a metal bench feels hotter/colder than a wooden one when they should be the same temperature.
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