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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

#511

Earlier quoted context omitted.

considering your foot is 2 standard deviations from the mean foot length, that hardly proves anything

Well it proves a lot in my opinion. Feet are really non uniform in length by a lot.

go to google and type "about definition"

Re: International System of Units overhauled in historic vote

#512
post #486

Earlier quoted context omitted.

You're right - imperial is far superior for precise building or manufacturing work. Take drill bits, for example. Obviously it's much easier to figure out that 11/32" is less than 3/8". Or is it more? No, I'm pretty sure I was right the first time. The metric ones with their 5.5mm, 6mm, 6.5mm sequencing are just too complicated to work with, in comparison. And half a millimeter isn't very precise - it's much bigger t…

Do I detect sarcasm here? I'm pretty sure I detect sarcasm here.

Much of the sarcasm targets the mixing of multiple units that is everpresent in imperial measurements. Feet + inches instead of one or the other?

Re: International System of Units overhauled in historic vote

#513
post #188

See, the US wasn't being stubborn in not adopting metric, it was just waiting patiently for it to progress from beta to 1.0. :) (Fun fact: all the US customary units have been officially defined in terms of their metric counterparts since 1893: https://www.nist.gov/sites/default/files/documents/pml/wmd/m... )

Where I'm from, it's a hybrid system. kg, celcius, litres and inches

Re: International System of Units overhauled in historic vote

#514
post #85
post #80

I can imagine that in 100-200 years we'll have to adjust some unit because our understanding of some constant was just slightly wrong.

According to the new definitions, some of the fundamental constants can no longer be wrong. We could even have defined them as 1 (which is what physicists have been doing for a long time already.)

If you do that, magnitudes of resulting units will either be huge or very tiny, depending on the composition of fundamental constants in said measure. The constants are very carefully chosen to match old units.

Re: International System of Units overhauled in historic vote

#515

Earlier quoted context omitted.

Because infinite numbers are not a natural expression of discrete measurements, and when it comes to being price 1/3 = 4 is always going to be easier to put your finger on than 1/3 = 3.333. I work in software and data analysis in the construction industry. A continuous measurement is good for some things, but it's definitely not good for discrete measurements. Furthermore, a lot of the people who work in the field fo…

What is stopping people from making meter sticks with 3000 lines, i.e. every third of a millimeter is marked? (The point is, there is nothing any more "infinite" about the rational number 1/3 than 1/4, 1/5, 1/2 or what have you. It just can't be written in the arbitrary base 10 system, just like 1/5 can't be written in base 12)

There is nothing stopping you from writing 1/3 meter.

Re: International System of Units overhauled in historic vote

#516
post #488

Earlier quoted context omitted.

My cupboard has cups in all kinds of sizes. Which one is the right one to use as a measurement? And for baking there's quite a big difference if my cups are 150 ml or 350 ml, especially when paired with counted ingredients like eggs. That's the problem with cups.

All of your regular coffee cups are exactly 250ml. Regular people use them for basic baking all the time, like making pancakes. 'Cups' are still better measures than ml because even you, in your self-acclaimed ignorance have a sense of how much a cup is whereas people do not have any idea how much '300ml' is. Canadians have no clue what 10ml of anything is. Canadians will continue to use feet and pounds for personal…

How can you be sure that "all of your regular coffee cups are exactly 250ml"? And what about teaspoon? And everything else?

Everyone here is obviously biased toward his/her own measurement system based on our experience, but the fact that "3 cups and a half of milk" is more precise than "875mL of milk" is clearly false.

Re: International System of Units overhauled in historic vote

#517
post #488

Earlier quoted context omitted.

My cupboard has cups in all kinds of sizes. Which one is the right one to use as a measurement? And for baking there's quite a big difference if my cups are 150 ml or 350 ml, especially when paired with counted ingredients like eggs. That's the problem with cups.

All of your regular coffee cups are exactly 250ml. Regular people use them for basic baking all the time, like making pancakes. 'Cups' are still better measures than ml because even you, in your self-acclaimed ignorance have a sense of how much a cup is whereas people do not have any idea how much '300ml' is. Canadians have no clue what 10ml of anything is. Canadians will continue to use feet and pounds for personal…

> whereas people do not have any idea how much '300ml' is.

No, you get a sense of this if you live somewhere that uses ml for things.

One can of soda is 330 ml.

Re: International System of Units overhauled in historic vote

#518
post #488

Earlier quoted context omitted.

"Recipes in cups are one thing I cannot understand" ?? You drink out of cups every day; this is what humans, even you understand. 'A scale' is inapplicable while you're buying food or reading labels. Why use a scale when everyone knows what a cup and teaspoon are? They are human measurements. But it doesn't matter what you use, what matters is what people understand, and they don't understand grams and millilitres. I…

My cupboard has cups in all kinds of sizes. Which one is the right one to use as a measurement? And for baking there's quite a big difference if my cups are 150 ml or 350 ml, especially when paired with counted ingredients like eggs. That's the problem with cups.

Especially if you're using things like flour where you get different quantities which if you sift it, or spoon it into the cup, or scoop it from the bag.

Cups are fine for rough and ready, but terrible for baking.

Re: International System of Units overhauled in historic vote

#519

Earlier quoted context omitted.

You've got it backwards. Counting to ten on your fingers predates the concept of our modern positional number system by hundreds of thousands of years. That's why base 10 was already the well-established natural choice when that system was invented. Thinking that you could represent the quantity IIIIIIIIIIIIIIIIIIIII by the string "21" because it's 2 * 10 + 1, or similarly as "three fingers on left hand, three finger…

I'm not sure what your point is. A numbering system based on five-fingered hands is still base6. It doesn't make mathematical sense to argue that we learn base10 today because our hands have 5 fingers. Even if you argue that we have 10 total fingers, that's base11. Does anybody advocate that? How did we come to such an arbitrary thing as base ten?

No, counting on the hands is not base anything, because positional number systems did not exist. Just like Roman numerals or tally marks aren't base anything.

People counted on fingers like with tally marks - they could express the numbers one through ten. Thus ten became an important and familiar number to humans. Thus it would have seemed natural to use a base 10 number system many millennia later.

Re: International System of Units overhauled in historic vote

#520
post #442
post #308

Earlier quoted context omitted.

It's true that (for example) a third of a metre isn't expressible accurately in decimetres, but you can always just say (continuing this specific example) "a third of a metre". Nobody will be confused about what you mean. This is however perhaps a good argument in favour of non-decimal currency.

It doesn’t matter. Just write 333.333 mm and if you make it evident in your construction drawing that three of these third meter-things need to fit one meter somebody might even calculate the width of the blade into it. Measurements are just a number and you will always have tolerances and chains of measurements to go with them to clarify what you expext as a end result.

Yes, good point - I was thinking about casual, everyday uses, but if you're going to be precise then the question of divisibility becames even less relevant. Just tack on as many decimal places as you need.

It's true that this applies just as much to non-metric units, of course! But then if divisibility isn't a big deal, this goes both ways - meaning that the disadvantages of the metric system's base 10 orientation may well be minor in practice, and not enough to outweigh the advantages.

(Actually though I think the metric system has you more cleanly covered for this sort of case, with its consistent set of prefixes for scaling up and down by 1,000. Non-metric units tend to be a random jumble of 8s, 12s, 16s, or worse.)

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