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International System of Units overhauled in historic vote

npl.co.uk

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Re: International System of Units overhauled in historic vote

#441

Post by atoav »

AngryData wrote: post #334
naikrovek wrote: post #238

Earlier quoted context omitted.

You are definitely (and thankfully) not the norm. Imperial units are awful. They're more ... human, maybe, in that a foot is about one human foot long, and that an inch is about one human thumb width, and how 0F feels "pretty cold" and 100F feels "pretty hot", and to me the charm of imperial units begins and ends right there. Those are literally the only redeemable qualities about imperial units, and they have nothin…

Fractional units are extremely useful in construction and machining. Now you could use fractions with meters, but nobody does, and im not sure why other than 10 is a shitty starting point for fractions and you end up with crazy fucked denominators.

The typical woodworker knows by hard all “crazy fucked” denominators like 333.333 mm for a third, 200 mm for a fifth etc.

The idea that not having straight fractional values somehow makes it harder is just plainly false. When you tell anybody to cut a third of a meter they will just happily cut 333.33 mm down to their usual tolerance

Re: International System of Units overhauled in historic vote

#442

Post by atoav »

tom_ wrote: post #308
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…

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.

Re: International System of Units overhauled in historic vote

#443

Post by vlasev »

gorn wrote: post #237

Recently I have been thinking about if any of our units makes sense in cosmic perspective. Let's take speed of light for example. It's approximately 300000 km/s. But then what is a second? It's 1/60 of a minute which is 1/60 of an hour which is 1/24 of a day(and so it goes) and all those numbers are arbitrary. A day doesn't make any sense outside our planet anyway, I doubt that there is another celestial body in the…

You might be thinking along the lines of natural units [1] or even Planck units [2], where you set some fundamental constants to 1 and take it from there.

[1]: https://en.wikipedia.org/wiki/Natural_units [2]: https://en.wikipedia.org/wiki/Planck_units

Re: International System of Units overhauled in historic vote

#444

Post by atoav »

deelowe wrote: post #262
devindotcom wrote: post #241

Earlier quoted context omitted.

I hadn't thought of some of these advantages. Some are subjective, but it's hard to deny the intuitive nature of others. I say bring back the span and the rod as well.

Go walk a job site with a tradesman and youll see why imperial is so useful and natural to them. They walk off long distancrs, use knuckles for small ones and do complex division with ease.

My father lays tiles for a living and he always did the same in metric, if he didn’t had something to measure things with him (which any professional should!)

A meter is basically a slightly longer step. I think most tradesmen over here got a pretty good sense how to walk a meter.

0.1m or 1dm or 10cm or 100mm is basically the width of your hand.

1cm or 10mm is roundabout the width of the pinky finger

Re: International System of Units overhauled in historic vote

#445

Post by atoav »

woodpanel wrote: post #277
mbroncano wrote: post #265

Earlier quoted context omitted.

Most probably because you grew up with it. I’m pretty sure you think the same about your religion, nation, race ... but be sure eveybody else in the world may think the same of their own. And they’d be right too. What I personally find disturbing is how irrational positions such as yours are commonly accepted in a supposedly advanced society. It leads to a pretty bumpy road, time and time again.

As a proponent of the metric system, I got to say the most disturbing thing is how an honest because openly subjective, intelligible and relatable statement (like the one OP gave) can be turned into something political and offensive. It it is the habit of doing this, that leads to a bumpy road ahead. But since we‘re talking politics: it were the „progressive“ Bauhaus proponents like Corbusier, that proclaimed that wh…

On top of that I don’t see how imperial is more human than metric. Yeah you have the foot bit a meter is a slighly longish step. Both units make you walk weirdly.

Re: International System of Units overhauled in historic vote

#446

Post by atoav »

blhack wrote: post #275
ape4 wrote: post #266

Earlier quoted context omitted.

I see you're not liking how many feet are in a mile (and many other silly things).

Well I also don't particularly care about how many feet are in a kilometer, since they are different units. A mile is...a mile. A half a mile, a quarter of a mile, an eighth of a mile, etc. Yeah, there are 5280 feet in a mile. There are also 25.8 or something like that mm in a inch, some other arbitrary unit of conversion that we all have to memorize.

These differences get important if you do any type calculation in engineering or physics.

Then it suddenly starts to matter if the result is Nm, Nmn or a Newton times a inch

Example: a Volt – which also the US uses with its metric prefixes – is defined as a Joule or a Wattsecond or a Newtonmeter.

Re: International System of Units overhauled in historic vote

#448

Post by xanipher »

ubernostrum wrote: post #289
bdamm wrote: post #264

Earlier quoted context omitted.

They're globally standard, decimal, and internally consistent. One never needs to wonder how many meters in a kilometer or how many grams in a kilogram. They have some human usable qualities as well; it's convenient that water freezes at 0°C and that a kilogram of water is also a liter.

a kilogram of water is also a liter I have never, in around four decades of living, had an actual need to determine the mass of a given volume of water, or the volume of a given mass of water. When cooking, I routinely need to split some quantity of an ingredient into thirds or quarters. Yet I am also constantly told that I'm ignorant and backwards and irrational for preferring a system that optimizes for the latter,…

But that's because your recipes are built on the easy divisibility, no? If your recipes are built on weight measurements, suddenly "easy divisibility" brings nothing to the table. If you cook with a kitchen scale, "one ml of water is one gram" is used all the time.

Re: International System of Units overhauled in historic vote

#449

Post by tempodox »

ZainRiz wrote: post #201
kibwen wrote: 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... )

Now can we redefine 1 pound to equal 1 kg? (the opposite of https://xkcd.com/2073 )

Nope, 1 pound should equal 0.5 kg.

Re: International System of Units overhauled in historic vote

#450

Post by atoav »

stass wrote: post #244
naikrovek wrote: post #238

Earlier quoted context omitted.

You are definitely (and thankfully) not the norm. Imperial units are awful. They're more ... human, maybe, in that a foot is about one human foot long, and that an inch is about one human thumb width, and how 0F feels "pretty cold" and 100F feels "pretty hot", and to me the charm of imperial units begins and ends right there. Those are literally the only redeemable qualities about imperial units, and they have nothin…

What are the redeamable qualities of metric units?

The metric prefixes we know and love are a huge plus. If you convert from Volt to kV or to mV, you just need to move your comma. Ah see what I did there? I uses a metric prefix on a unit that is also used in the US.

The thing is 1V is also 1Nm or 1J or 1Ws. So suddenly we have the meter there right besides the Newton. In fact if you look beyond "I build my own shed in the US"-scenarios, you will find the meter everywhere intertwined in the definition of other units. In fact the definition of imperial length units is based on the metric definition of the length light travels through vacuum in 1/299792458s. So the foundation of the meter is light speed, which helps with all kind of practical issues in physics.

The metric system has maximum compatibility to all these unit systems (except the °C which is a more-practical-for-every-day-use offset version of Kelvin).

Unit systems are always something you grow up with and are therefore an emotional topic. People will take fractions of inches as an example of how metric fractions fail to deliver, when in fact no european woodworker has even remotly a problem with doing their thing in mm. In front of me lies a ruler with a 0.1mm scale and a caliper with 0.01mm or 1/128In accuracyIf I really wanna be ±0.01mm accurate on a cut of 1/3m or 333.33mm getting that accuracy would not be easier in inches. My saw blade is precisely 2mm wide anyways..

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