Should the USA go metric?

[damerell]

Never had to measure the volume of too many compressable substances in my kitchen.

Flour is an obvious one.

I'll guess brown sugar (with molasses) counts as one of them; Usually when measuring a cup of it, it's intended it's packed into the cup.

Yes. Specifying (or not specifying, but expecting people to know) how to pack it is a workaround; weighing it is a bugfix.

[wdsmith3]

Argument for metric system:

Base 10 (easier calculations)

Internationally recognized and understood

already used by scientific community

Argument against:

because America

[Bill Phil]

Argument for metric system:

Base 10 (easier calculations)

Internationally recognized and understood

already used by scientific community

Argument against:

because America

The only way metric is more base 10 than imperial is that there are names for multiples of ten for the base unit.

A kilometer is not a unit. It's short for One Thousand Meters. The unit is meters, with a prefix telling you how many.

I could say kilo yards, and people who know what kilo and yard mean will probably understand it. That's a thousand yards.

There just happens to also be many other units of distance in imperial, and that's where complication starts.

"Because America" is a pretty big insult. The government uses metric, it's the people who don't. Probably because of some stereotyping of the rest of the world or something. Americans want to cling to things that are american. Such as the system of units. And it doesn't really affect that many people adversely. People here have trouble when going to Europe as well.

Metric is more logical, but it's not "better". It's not "worse" either. The only advantage it has over Imperial is that it is adopted by the majority of the world. That's a big one, so maybe people should switch. But it would be over time.

[Camacha]

Metric is more logical, but it's not "better".

The fact that's it more logic makes it better. Conversions are easier too. Saying otherwise seems a futile attempt to deny how things are.

The imperial system functions, but that does not make them equal. It really is not a matter of being used to or anything like that.

[SeaDog]

You misunderstood.

My reply was to the suggestion that one should use a measuring cup for cooking purposes, which is not very useful in Europe, since dry ingredients are usually expressed as mass.

Maybe I'm going off topic here, but the only time ingredients are measured in mass here in Sweden is when it is actually more practical. That pretty much only happens when the recipe is aimed at large producers who get their flour in large bags that might compress the flour so that weight is the only accurate measure.

Butter is one of the few things you see in terms of mass in regular recipes here, and thats because the packaging shows how much 50 grams etc is.

[Bill Phil]

The fact that's it more logic makes it better. Conversions are easier too. Saying otherwise seems a futile attempt to deny how things are.

The imperial system functions, but that does not make them equal. It really is not a matter of being used to or anything like that.

Logic is not better in all cases. For civilian purposes, day to day life, something more common than scientific endeavors and engineering ones, and thus more important to how this should be judged, they're equal. It's only better for the scientific community and similar communities , but only because it is not as complicated. Which is always better for scientists and engineers and the like, which is great, but they have all already adopted metric. At least for the most part.

They're not really conversions, you're just saying the same number in a slightly different way.

I'm not denying how things are, I'm looking at this in an unbiased way. I like metric more than imperial, but there's no reason to be biased by my opinion.

The imperial system is not the best, true. I'm not arguing for it or against it. But metric is not the best either. Something else is, something that has yet to be made.

The American public, on average, prefers tradition. A transition period will happen, where more people in the States understand both systems, and this is when everything will start switching over. Eventually less and less of imperial will be taught, and it will go away. But there's no reason to force people to switch. It'll happen, eventually.

[*Aqua*]

But metric is not the best either. Something else is, something that has yet to be made.

Could you elaborate this? I wonder why you think that way. I can't imagine a case where metric is insufficient.

[Camacha]

Logic is not better in all cases. For civilian purposes, day to day life, something more common than scientific endeavors and engineering ones, and thus more important to how this should be judged, they're equal. [...] They're not really conversions, you're just saying the same number in a slightly different way.

But it is useful in everyday life, that is what I have been saying all along. If I do not have a measuring cup, but do have a scale, I can weigh the fluid and have a very close approximation of the volume of any kitchen or other everyday fluid. That is not expressing the same number in another way, that is actually converting. Though expressing numbers in different ways also becomes a lot easier.

I can convert the length a swimming pool from 0,05 kilometres to 50 metres without thinking, and if that pool is 200 centimetres deep and 20 metres wide I can tell you there 2 million litres of water in there weighing 2000 metric tonne without even glancing at a calculator or piece of paper. Even though not everyone builds swimming pools every day, quickly and accurately guesstimating weights and volumes in situations where you are, I don't know, carrying stuff around on a trailer or something similar can prevent major issues.

I do not even have to do the same calculation using miles, inches and feet to pounds and gallons to see that will be an utter mess.

But metric is not the best either.

It is the best we have, and importantly, still adapt it to be better.

Edited June 18, 2015 by Camacha

[peadar1987]

The only way metric is more base 10 than imperial is that there are names for multiples of ten for the base unit.

A kilometer is not a unit. It's short for One Thousand Meters. The unit is meters, with a prefix telling you how many.

I could say kilo yards, and people who know what kilo and yard mean will probably understand it. That's a thousand yards.

There just happens to also be many other units of distance in imperial, and that's where complication starts.

"Because America" is a pretty big insult. The government uses metric, it's the people who don't. Probably because of some stereotyping of the rest of the world or something. Americans want to cling to things that are american. Such as the system of units. And it doesn't really affect that many people adversely. People here have trouble when going to Europe as well.

Metric is more logical, but it's not "better". It's not "worse" either. The only advantage it has over Imperial is that it is adopted by the majority of the world. That's a big one, so maybe people should switch. But it would be over time.

That's a pretty big way that it's more base ten though! 12 inches to a foot, 3 feet to a yard, 1700-odd yards to a mile. How many inches are there in 463 miles? Excuse me while I bust out my calculator.

Compare metric, 100 centimetres to a metre, 1000 metres to a kilometre. How many centimetres in 463 kilometres? I just move the decimal point: 46,300,000cm.

And that's before you get to units that have multiple components. How many N/m^2 in 288 kN/cm^2? Move the decimal point again. 2,880,000,000 N/m^2.

How many lbf/square foot in 288 tonnes/square inch? I'll be happy if I complete that calculation in less than a minute.

[Wesreidau]

Flour is an obvious one.

Flour sifter, which you should do anyway. It greatly improves the texture.

Yes. Specifying (or not specifying, but expecting people to know) how to pack it is a workaround; weighing it is a bugfix.

I assume when you weigh 400 grams of brown sugar you made sure it wasn't wet.

[Camacha]

I assume when you weigh 400 grams of brown sugar you made sure it wasn't wet.

Wet brown sugar will be obvious enough, as it will remain inside the package as one huge lump

Edited June 18, 2015 by Camacha

[ZetaX]

To add a new but quite formal approach: metric has higher entropy. So what does this mean¿ Well, in layman's terms, you need on average less symbols to express the same thing.

Understanding why needs a bit of explanation:

There is something called scale-invariance which is true for (almost) all sizes (significantly above quantum and below relativity). It amounts to the fact that for any fixed c>1 (c=10 is standard, but any other like c=2 or c=pi work equally well), things of size x and size cx are equally likely. A bit more mathematically: probability is equally distributed on a logarithmic scale. The reason from physics is the scale-invariance of its laws.

This has some paradoxical effects: a majority of sizes, lengths, areas, volumes you encounter will start with a 1, 2 or 3 (in base 10); already around 48% start with 1 or 2. This is true regardless of the units used, as long as you use the very same unit each time, be it meter, yard or miles.

Call such unit u. So if we let c be the square root of 10, then something of size in [u,cu] happens as often as something of size in [cu,c²u] = [cu,10u]. Thus for numbers between u and 10u, being below cu is as likely as being above it. But c is roughly 3.16 and surely lower than 4. So a majority of numbers is between u and 4u, in othe words start with 1, 2 or 3.

If you want to know more details look at https://en.wikipedia.org/wiki/Benford%27s_law.

In the end, this implies that a system of several units (..., µm, mm, m, km, Mm, ... versus ..., foot, yard, mile, ...) works best if they are equally spaced apart. This is true for metric, and also for the digital prefixes, but not for imperial.

A kilometer is not a unit. It's short for One Thousand Meters. The unit is meters, with a prefix telling you how many.

I could say kilo yards, and people who know what kilo and yard mean will probably understand it. That's a thousand yards.

There just happens to also be many other units of distance in imperial, and that's where complication starts.

And that's exactly where metric is better: Occam's Razor (extended to other things than hypotheses/theories). It uses a smaller amount of basic units (but not minimal, e.g. there are litres and cubic metres; the former is thus quite redundant) and then simply adds the prefixes (that also exist in other systems) to it.

[SuperFastJellyfish]

"We choose to use imperial measurements not because they are easy, but because they are hard."

-JFK

[linkxsc]

That's a pretty big way that it's more base ten though! 12 inches to a foot, 3 feet to a yard, 1700-odd yards to a mile. How many inches are there in 463 miles? Excuse me while I bust out my calculator.

How many lbf/square foot in 288 tonnes/square inch? I'll be happy if I complete that calculation in less than a minute.

Excuse me while I sit and contemplate why I would ever need to know the inches in 463 miles. Or converting tons/sq foot to sq in.

Ps its 2 ton/in sq took all of about a 3rd of a second to get. And FYI you rarely ever judge things like that. More realistically would be lbs per inch on a beam (figuring the moments and shear along a beam)

Honestly I can throw any number of useless groupings of numbers out there to have you try and judge how easy math is.

And all of these problems you all keep doing are easy round numbers.

Try this on for size. Whats the volume of a cylinder 880mm tall, and 610mm in diameter?

[PakledHostage]

Try this on for size. Whats the volume of a cylinder 880mm tall, and 610mm in diameter?

I'm not sure I get your point? We all learned how to calculate the volume of a cylinder in about grade 7 or 8? If you work your example, you get an answer in cubic millimetres. There are 1 billion cubic millimetres in a cubic metre and 1000 litres in a cubic metre. If you divide the magnitude of your answer in cubic millimetres by 1 million (1x10^9/1x10^3), you'll get the volume in litres.

[Camacha]

I'm not sure I get your point?

I am really not sure people are oblivious to the advantages or intentionally misrepresenting them.

[Whovian]

Excuse me while I sit and contemplate why I would ever need to know the inches in 463 miles. Or converting tons/sq foot to sq in.

Ps its 2 ton/in sq took all of about a 3rd of a second to get. And FYI you rarely ever judge things like that. More realistically would be lbs per inch on a beam (figuring the moments and shear along a beam)

Honestly I can throw any number of useless groupings of numbers out there to have you try and judge how easy math is.

And all of these problems you all keep doing are easy round numbers.

You seem to have missed the point. Very few people can multiply by 2000/144 in 1/3 of a second. Everyone can multiply by 10^n for integer n in 1/3 of a second. Metric makes unit conversion require no thought at all for people who work in base 10, while the imperial system has seemingly arbitrary conversion rates that make it rather bulky and distract from the task at hand.

Try this on for size. Whats the volume of a cylinder 880mm tall, and 610mm in diameter?

The appeal of metric is that it makes unit conversion problems easy, ergo peadar's post. Whether calculating volumes of cylinders is easy is completely irrelevant to this. If I made you multiply 7 by 8 using only Zeckendorf representations of numbers, would the fact that estimating the Gaussian integral is just as easy in base 10 as with Zeckendorf representation subtract from the fact that Zeckendorf is extremely impractical?

Edited June 19, 2015 by Whovian

[ZetaX]

If I made you multiply 7 by 8 using only Zeckendorf representations of numbers, would the fact that estimating the Gaussian integral is just as easy in base 10 as with Zeckendorf representation subtract from the fact that Zeckendorf is extremely impractical?

How the heck do you plan to do arithmetics of non-integer reals with Zeckendorf representations¿

But you made me think about how to multiply integers in Zeckendorf representation and so far I have not come up with anything significantly better than "split it down into a looong sum of 1s". Is there any reasonable formula of type F_a · F_b = [some sum of F_i's]¿

[linkxsc]

The appeal of metric is that it makes unit conversion problems easy, ergo peadar's post. Whether calculating volumes of cylinders is easy is completely irrelevant to this.

Aha but see heres what im trying to get across. You arent going to be calculating the volume of that cylinder in your head now are you. You're gonna break out a calculator, hash it out on paper. Or innately know that 610/880 is actually 24in/35in, and is a regular 55gallon(208l) drum.

You didnt even pick up on that I answered the weight over area question wrong either. And then you make it better with your 2000/144. 288 tons per sq inch into lbs/sq ft is 288x144x2000= some big number in the ballpark of 80million lbs per ft.

And even someone else figured it wrong at a glance.

Though ill give points for a classic "write the question backwards and see if they work it backwards" ploy. My thermo teacher love the things.

Here lemme try 1

Whats the Hectograms per square Decimeter, of 980 kilopascals. (2 si prefexes that are about as arbitrary as furlongs per fortnight if you ask me, also the 980 is specific for tripping you up)

But at no point in this will you be doing stuff in your head. And rarely (if ever) are you going to need this easy mental unit conversion.

Any time any of this actually matters, is when doing any kind of serious math. And in the real world this isnt done in peoples heads. Because wether Im going from miles to feet, or kilometers to centemeters, its going to be done on paper, or a calculator. Because its just as easy to misplace a factor of 10 in mental math as it is a factor of 12, 5280, or a 2.54

Edited June 19, 2015 by linkxsc
I suck at spelling on my phone

[damerell]

Flour sifter, which you should do anyway. It greatly improves the texture.

Which is down to a hidden assumption about compression. Or, you know, you could not try and measure compressible substances volumetrically.

I assume when you weigh 400 grams of brown sugar you made sure it wasn't wet.

Well, yes, since the recipe calls for sugar, not sugar+water. Just as when you measure anything in cooking you don't mix it with something else first.

- - - Updated - - -

"Because America" is a pretty big insult. The government uses metric, it's the people who don't. Probably because of some stereotyping of the rest of the world or something. Americans want to cling to things that are american. Such as the system of units.

The system they (incorrectly) call Imperial, right? So American (they think) it's called after the British Empire?

[linkxsc]

Which is down to a hidden assumption about compression. Or, you know, you could not try and measure compressible substances volumetrically.

Never ran into a recipe where the tolerances on ingredient measure were so tight, the the compressability of my flour mattered. Thoguh, I guess I coukd squeeze down my flour real hard and see just how far off I get from normal.

Hmm are there any tables out there listing the compressability of common powdered baking ingredients? I know you can get them for sand and gravel.

[Pingonaut]

God yes. I hate out system.

[*Aqua*]

Or innately know that 610/880 is actually 24in/35in, and is a regular 55gallon(208l) drum.

Do you really expect him to know about imperial conversion factors? Nobody outside the USA cares about x inch/y inch => z gallons. We don't need to remember these 'lucky' numbers.

If we need a length, we measure it in m(eters). If we need an area, we are multiplying m*m=m². If we need a volume, we are multiplying either m*m*m=m³ or m*m²=m³. We simply don't have to convert lengths and areas to a specific unit before to get an easy conversion factor. That makes a lot of calculations much, much easier because you have less chances to mess up.

2 si prefexes that are about as arbitrary as furlongs per fortnight if you ask me

Now I get it! You didn't understand what we are talking about. Ok, just for you again: It's not about that you are using inch, foot and who-knows-what. It's about that you have a different conversion factors for all of the units. And these factors don't make sense because they don't follow a logic. Sometimes the factor is a 3, then it's a 4 then it's a 16. The metric system doesn't need that. That's the difference and that's all this thread is about.

[linkxsc]

Still not seeing you solve that problem.

Mind you, I have to pull out a paper just to track all the units involved with 2 "simple" unit conversions there. (Guess it wasnt units tracking though, more of prefixes)

Also this thread is about should the US switch. Not about the differences between the systems.

The thread is derailed though from the initial point though into a contest of "our system is better" because officially, we are metric already.

The changeover is already happening and has been gradually going for years.

Wonder how long itll be till the world stops using 40ftx8ft shipping containers though, filled with 4ftx4ft palates (which on the note of that barrel thing. You can fit 4 of on a palate for shipping)

[peadar1987]

Excuse me while I sit and contemplate why I would ever need to know the inches in 463 miles. Or converting tons/sq foot to sq in.

Ps its 2 ton/in sq took all of about a 3rd of a second to get. And FYI you rarely ever judge things like that. More realistically would be lbs per inch on a beam (figuring the moments and shear along a beam)

Honestly I can throw any number of useless groupings of numbers out there to have you try and judge how easy math is.

And all of these problems you all keep doing are easy round numbers.

Try this on for size. Whats the volume of a cylinder 880mm tall, and 610mm in diameter?

Are you an engineer? Strange unit conversions crop up all the time. Especially forces over areas, which are just stresses.

Your cylinder question is pretty irrelevant. PI*r*r*h is a formula that will be nice, or horrible, depending on the specific numbers you plug into it, regardless of how many inches are in a cubit. Where it starts to be a problem is when you need to know how many cubic inches are in a gallon, which is the sort of problem that would come up if you were trying to fill a large volume using containers of a smaller volume (a very common situation).

Aha but see heres what im trying to get across. You arent going to be calculating the volume of that cylinder in your head now are you. You're gonna break out a calculator, hash it out on paper. Or innately know that 610/880 is actually 24in/35in, and is a regular 55gallon(208l) drum.

And if you have to convert cubic inches to gallons after working out the volume of the cylinder, it adds an extra layer of complexity over just shifting a decimal point. Adding in standard imperial drum sizes to remember only complicates things further. How many cubic feet to fill the 55 gallon drum? How many 55-gallon drums to fill a 40 cubic yard tank?

You didnt even pick up on that I answered the weight over area question wrong either. And then you make it better with your 2000/144. 288 tons per sq inch into lbs/sq ft is 288x144x2000= some big number in the ballpark of 80million lbs per ft.

And even someone else figured it wrong at a glance.

The fact that it wasn't immediately obvious that your answer was wrong doesn't really support your point mate!

Whats the Hectograms per square Decimeter, of 980 kilopascals. (2 si prefexes that are about as arbitrary as furlongs per fortnight if you ask me, also the 980 is specific for tripping you up)

980,000 N/m^2.

Divide by 9.8 to get a mass: 100,000 kgf/m^2

Multiply by (10*10) to get per decimetre: 1,000,000,000 kgf/dm^2

Divide by 10 to convert kilograms to hectograms: 100,000,000 hgf/dm^2

Easy. The 9.8 conversion factor from a force to a mass is the only time you don't just have to move a decimal point, and even then you can get to within 2% by doing so.

But at no point in this will you be doing stuff in your head. And rarely (if ever) are you going to need this easy mental unit conversion.

Any time any of this actually matters, is when doing any kind of serious math. And in the real world this isnt done in peoples heads. Because wether Im going from miles to feet, or kilometers to centemeters, its going to be done on paper, or a calculator. Because its just as easy to misplace a factor of 10 in mental math as it is a factor of 12, 5280, or a 2.54

And even on paper, it's easier to just hop a few places with your pencil to signify a factor of 10 conversion than it is to do a full long multiplication, or even to plug a value into your calculator.