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International System of Units overhauled in historic vote

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Re: International System of Units overhauled in historic vote

#371

Post by Symbiote »

Just_Smith wrote: post #300
naikrovek wrote: post #287

Earlier quoted context omitted.

Because adding 7/16ths of an inch to 7/8ths of a mile and getting an answer in inches isn't easy for a human. Adding 1cm to 982m and getting an answer in centimeters is dead easy for a human. THAT'S why human intuition about measurement doesn't mean a damn thing. Using metric means using the system optimized for humans. Period.

Your absolutism is a bit silly. I don't think the Imperial system is good for anything beyond construction or cooking, but there's a reason it excels those areas. And it's exactly because it's more usable by humans in certain contexts (like construction or cooking). 1/3 of a meter should not be an irrational number - how is that "optimized for humans"? A scalable system that shares the divisibility of the foot would…

If you want to measure ⅓ metre, go ahead. Nothing stops you from doing that.

The usual convention in construction in Europe is multiples of 150mm, for example a typical large appliance is 595mm wide to fit a 600mm wide space.

Re: International System of Units overhauled in historic vote

#372

Post by evil-olive »

bkanber wrote: post #328
kmm wrote: post #304

Earlier quoted context omitted.

I can just barely feel the difference of temperature of one degree Celsius. I really don't feel multiplying that by 1.8 will make a big difference in how good a scale it is for humans.

As an example, the common temperatures in NYC range from 0-100F. In celcius that's like -18 to +38. I'm a scientist and an engineer, and in those applications C is often better. But in daily life, Fahrenheit makes a ton of sense.

Just think about it by 10s, as you do with the metric system:

20 C - a bit less than room temperature (68 F)

30 C - pretty hot (86 F)

40 C - very hot (104 F)

And going the other way:

10 C - a bit chilly (50 F)

0 C - cold (32 F)

-10 C - real cold (14 F)

-20 C - really really cold (-4 F)

When you hear a temperature in Celsius, don't try to convert it to Fahrenheit, just think in Celsius. 15 degrees is halfway between "chilly" 10 C and "room temp" 20 C. One degree of warming - say 26 C to 27 C - is pretty easy to conceptualize when you have those 10-degree reference points.

Re: International System of Units overhauled in historic vote

#373

Post by anamexis »

redial wrote: post #356
bkanber wrote: post #328

Earlier quoted context omitted.

As an example, the common temperatures in NYC range from 0-100F. In celcius that's like -18 to +38. I'm a scientist and an engineer, and in those applications C is often better. But in daily life, Fahrenheit makes a ton of sense.

In Ecuador the temperature ranges from ~60 to ~90F, but I'm sure for them is a great relief to know people of New York have a temperature unit that perfectly matches their climate as neatly as going from 0 to 100.

But is 15C to 32C better?

Re: International System of Units overhauled in historic vote

#374

Post by quantum_magpie »

autokad wrote: post #250
blhack wrote: post #232

Earlier quoted context omitted.

I'm one of the weird people that actually really likes imperial units. For instance: 1 foot -- base 12. This is a superior base to 10. It can be easily divided into 4ths, 3rd, and 2nds. Base 10 can only easily be divided into 2nds. 1 inch -- an easily identifiable unit of measure for smallish things. About the width of my thumb. A pretty good unit. For low precision, inches become 1/2, 1/4, 1/8, 1/6, 1/64, etc. Each…

I feel like imperial units are human units. they are units used on a human scale, where as metric are more 'computer'. example: a human really cant look at something and divide it by 10 very well, but 1/3, 1/2, 1/4, very easy to do. the sizes makes human sense, like a foot being about a human foot, etc.

But they're not! My foot is 25cm, far from '1 foot'. My thumb is 1.5 cm wide, far from an inch. The metric system is actually much more human for me. And I never needed to measure 1/3rds to 0.02mm precision without a precise measurement instrument. And if exact precision doesn't matter then all these arguments about fractions are moot, too!

Re: International System of Units overhauled in historic vote

#375

Post by Symbiote »

sib wrote: post #342
zjaffee wrote: post #305

Earlier quoted context omitted.

While I agree that in many ways imperial is better than metric in the way that you mention. It is absolutely atrocious when it comes to weight and volume. A gallon is still a base 10 unit of measure of water (10 pounds of water). Then only after that, is it in base 8 rather than maintaining that base 12 consistency. Then if you look at imperial units of weight, it deviates away from base 12 again. It counts upwards f…

>> "A gallon is still a base 10 unit of measure of water (10 pounds of water)." Not sure what you are getting at here. A gallon is about 8.3 lbs (3.8kg). A gallon is 128 oz, a nice base-2 number.

You are arguing the difference between an imperial gallon and a US gallon.

Further evidence of how stupid these measurements are.

Re: International System of Units overhauled in historic vote

#376

Post by fuzzfactor »

Nursie wrote: post #359
nhebb wrote: post #330

Earlier quoted context omitted.

A pint is what British people drink in pubs while chastising the US for not adopting the metric system.

568ml, as god intended. Not some 450ml abomination! We don't really use pints for measuring anything else these days.

You are benefitting from the true Imperial pint where there is 4546 mL per gallon.

And of course 4 quarts to the gallon and two pints to the quart.

Otherwise like in the US in what is commonly known as the English system there is only 3785 mL to the gallon.

Re: International System of Units overhauled in historic vote

#377

Post by Symbiote »

NeedMoreTea wrote: post #365
jodrellblank wrote: post #333

Earlier quoted context omitted.

"It cannot perfectly represent the amount" you say, and then perfectly represent the amount. You represent a quarter as the fraction 25/100ths to show how impractical it is, instead of writing 1/4. Would it be so hard to build a ruler with thirds measured on it, so you don't need to try and guess 0.333333 from mm readings? Like http://teaching.monster.com/nfs/teaching/attachment_images/0... but made of metal

Buy an imperial rule. There's some inches that are sub-divided into tenths (maybe 1/20), and others sub-divided into sixteenths (maybe 32nds or 64ths). Often with heavier markings on more significance. For easy division and fractioning of whatever it is you are doing. If it's imperial only (v. rare nowadays) there's usually a coarser scale or two for easier subdivision or when the 16ths and finer just don't matter. B…

How often is the distance you need to divide a whole number of inches anyway?

No more often than it is a multiple of 12mm, 60mm, or whatever.

Real distances are either designed for easy calculation, like my N*150mm kitchen pieces, or are some random length.

Re: International System of Units overhauled in historic vote

#378

Post by mherdeg »

fengb wrote: post #276
mherdeg wrote: post #147

Earlier quoted context omitted.

The kilogram was the last one -- we're out of SI base units. This was the last one not defined based on some measurable universal constant, per https://en.wikipedia.org/wiki/SI_base_unit and https://en.wikipedia.org/wiki/Redefinition_of_SI_base_units . The meter was originally an actual physical rod (you can see the prototype on display at the fascinating French Musée des Arts et Métiers). Now it's based on the speed…

Mole was just redefined as exactly 6.02214076e23 — the number of Si-28 atoms in a perfect 1 kg sphere. This was an intentionally check against the kibble balance measurement. More info from an older Veritasium video: https://www.youtube.com/watch?v=ZMByI4s-D-Y

Yeah, I had totally missed that a change was in the works to redefine Avogardo's number as an exact number with no uncertainty. Pretty cool.

Re: International System of Units overhauled in historic vote

#379

Post by djwbrown »

EricBurnett wrote: post #324
blhack wrote: post #232

Earlier quoted context omitted.

I'm one of the weird people that actually really likes imperial units. For instance: 1 foot -- base 12. This is a superior base to 10. It can be easily divided into 4ths, 3rd, and 2nds. Base 10 can only easily be divided into 2nds. 1 inch -- an easily identifiable unit of measure for smallish things. About the width of my thumb. A pretty good unit. For low precision, inches become 1/2, 1/4, 1/8, 1/6, 1/64, etc. Each…

Hmm, good for usage you say. Ok, let's stick to "standard" imperial units. How many feet in a yard? Yards in a mile? What the hell is a quart? And since base 12 is great, what is 12 feet called? 144 feet? A 12th of an inch? Or, ounces: How many ounces in a gallon? A pound? And how many _kinds_ of ounces are there, anyways? Fun fact: The term “ounce” is of Latin origin from the word “uncia” which means “a twelfth part…

> So...what's an ounce a twelfth of?

It's a twelfth of a troy pound, or Roman libra (lb).

These two episodes from The History of English podcast trace these seemingly arbitrary units through history and give them some context. My favorite is the derivation of 5280 feet per mile. Also, that "mark twain" is a depth sounding of two fathoms.

http://historyofenglishpodcast.com/2018/07/26/episode-114-th... http://historyofenglishpodcast.com/2018/08/21/episode-115-th...

Re: International System of Units overhauled in historic vote

#380

Post by evil-olive »

anamexis wrote: post #294
Terr_ wrote: post #273

Earlier quoted context omitted.

> The freezing and boiling points of water are also not particularly pragmatic points of reference. I must strongly disagree. The freezing point of water is an incredibly important and pragmatic point of reference for hundreds of millions of people around the world, who live in places where water can freeze (or thaw) on its own outdoors. Not just for transportation, but also its affect on biology in agriculture. Whil…

I'll concede that freezing is very important to a lot of people, but at the same time, I don't think it's particularly onerous to remember that the freezing point is 32 degrees. As far as boiling and cooking, I would argue that there is no magic number anyways, since boiling point is variable by elevation. At 7500 feet / ~2250 meters, water boils at 198°F.

> As far as boiling and cooking, I would argue that there is no magic number anyways, since boiling point is variable by elevation. At 7500 feet / ~2250 meters, water boils at 198°F.

That's an excellent point, let's examine the relationship between altitude and boiling point, in both American units and everywhere-else-in-the-world units [0]:

5000 feet -> 202.97 F

7500 feet -> 198.33

10000 feet -> 193.6 F

Compared to:

1000 meters -> 96.73 C

2000 meters -> 93.38 C

3000 meters -> 89.95 C

In both cases, the boiling points at altitude are magic numbers. The difference is that with Celsius, you can interpret degrees as "percentage of the way from freezing to boiling". Going from 100 C at 0 meters to 90 C at 3000 meters is immediately meaningful as a 10% decrease. With degrees Fahrenheit, that same 10% drop in boiling temperature that happens at around 3000 meters / 10,000 feet is 212 F to 194 F.

0: https://www.omnicalculator.com/chemistry/boiling-point-altit...

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