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[olemars]

Kelvin is the base unit for temperature in SI.

Fun fact: The Celsius scale was originally defined as 0 at the boiling point for water and 100 at the freezing point.

[Starver]

Personally, I want to know how to convert my sensible metric into your insane Imperial systems. Any system that was founded on 'all our measurments are based on whatever happened to be nearby" is one that should ever have lasted beyond 1700. What the hell sort of standardised unit is a "stone"?! Was it conceptualised in some sort of stone-deficient town where they only had one rock, and assumed that all the rocks in the world must be roughly similar in weight or something?

Well, someone was messing about with pebbles from the stream, tentatively, unsure of himself about whether to use them.  But then he got a little boulder.

(Boulder.  Bolder.  Gettit?)

[Starver]

Still unable to grasp the Fahrenheit <-> Celsius conversion. Them fractions...

I know there's a handy fraction people use, but all I ever bother to remember is that -40==-40 and 0==32, and work the ax+k slope out in my mind every single time I need it, if I'm not just checking whether it's "too hot for ice" or not.

(And to show how I do it and as an example that I might use to check against the boiling point of water (at standard pressure, of course), well, obviously 40C°[1] = 72F°, so I'll simply multiply by 2.5 on each side and 100C° above freezing (100°C) is 180F° above freezing (or 212°F).  That number rings a bell.  Am I right?)

Of course, should I be working in Kelvin, I know that it is a 273.15 (close enough for most purposes) degrees translation from the Celsius scale, but I don't have too much liquid helium at home needing that much care and attention.  (And while I might have had some solid carbon dioxide, what happened to it was just too, too sublime...[/NoelCoward])


[1] Celsius degrees, rather than Degrees Celsius.  You understand the difference, I'm sure.

[Starver]

Celcius is based on the freezing point of pure water at sea level, which makes less sense the Farheinheit which is based on the average range of tempeture range of Europe for describing weather

...only in Europe.  I don't know why most of the world would have to work to a vague regional standard as opposed to something that may be terracentric (hello all you aliens!) but that at least all the world (that has access to Sea Level) can test for themselves once they can agree on the 'standard' pressure.

and less sense then Kelvin for scientific use

Any, absolute-zero origined measurement is useful for scientific use (where most of the effects are proportional to or otherwise an untranslated mathemetical function of such a zero-based system).  You can use Rankine if you like the magnitude of Fahrenheit degrees, to much the same result (apart from the precise factor you use in your equations).

So with celcius, you have a smaller whole number range to describe the weather and it tends to use a lot of negative numbers and fractions as a result.

I don't see either of them to be an issue.  35 degrees F or 37 degrees F, it's cold.  Ok, so between 33 and 31 degrees F it's a difference between actually freezing, or not, but otherwise a couple of degrees F won't matter in people's everyday meteorological experiences.  And if you use C than you know that a negative number means that it's freezing, a positive one means it's not, although if a single digit it might as well be if you're only wearing your bikini.

Anyways, a quick way to roughly convert Celcius to Farheinheit in your head is to double the number and add 30, So 20C is 70F, 10C is 50F, ect its gets you pretty close if you have to decipher weather forecasts in Europe or whatever (and isn't a negative number).

That sounds a bit more inaccurate than the 3/5ths (or whatever) system that I've already described how I avoid.  Obviously you don't mean to use it for such an extreme, but 100°C->230°F...  Well, closer than I thought it would be to the 212-ish value I would have derived.  Yeah, Ok.  But I still prefer my conversion method.

Fun fact: The Celsius scale was originally defined as 0 at the boiling point for water and 100 at the freezing point.

Yup.  Also look at the Delisle scale.  Zero at BP of water, 150 at MP of water.  Don't forget that people had different thoughts about the likes of heat and temperature, and it was probably logical at the time!  (But why 150 degrees betwixt those two points?)

[Muz]

I'd like to point out that metric is based off completely arbitrary benchmarks as well.

All metric distance measurements are based off the meter, which is based off a flawed measurement of the earth's diameter from the French Revolution period (was supposed to be 40,000 km for the diameter of the earth when in reality it's 40,075.017 km) . Then in 1983, they decided a meter is the distance light travels in vacuum in 1 ⁄ 299,792,458th of a second, which is a pretty damn illogical and arbitrary number, I think, especially since time measurements are based off an inaccurate measurement of solar and lunar cycles.

The gram is based off the meter, so the whole metric weight system is based off an arbitrary value as well.

Celcius is based on the freezing point of pure water at sea level, which makes less sense the Farheinheit which is based on the average range of tempeture range of Europe for describing weather and less sense then Kelvin for scientific use. So with celcius, you have a smaller whole number range to describe the weather and it tends to use a lot of negative numbers and fractions as a result. A more logical and scientific measurement system would be Kelvin, which is based on the temperature of absolute zero. No negative values with that system.

Anyways, a quick way to roughly convert Celcius to Farheinheit in your head is to double the number and add 30, So 20C is 70F, 10C is 50F, ect its gets you pretty close if you have to decipher weather forecasts in Europe or whatever (and isn't a negative number).

I wouldn't say it's completely arbitrary. There's some foundation there, and they're basing it off each other. You have to start measuring things somewhere, and basing it off some flawed measurement of the earth beats basing it off some king's foot or penis. The imperial system is a lot harder, while at least for metric, they put an effort to keep it base 10 and easy to convert to each other.

I've thought Celsius was the easiest to get right. 0 is freezing point, 100 is boiling point. Kelvin uses the same increments of Celsius, just that they set their 0 point at the minimum physically possible.

[malloc]

I've thought Celsius was the easiest to get right. 0 is freezing point, 100 is boiling point. Kelvin uses the same increments of Celsius, just that they set their 0 point at the minimum physically possible.

Celsius is actually quite handy, especially if you want to study physics, as the scale is the same as in kelvin, just add 273. (25C = 273 + 25) and kelvin well, it's based of absolute zero, and it increments in 1/100 of the difference in temperature from water freezing temperature to water boiling temperature at about 10000 pascal pressure, so in way it's based of two physical properties.

Also please people, the SI system is not based on arbitrary numbers. Most of it is based of physical constants, only the unit of mass is not, it is based of the weight of the kilo prototype. But this will be changed in the future, as they will change to be based of planks constant. Which will mean that all units will have their origin in the world of physics.

[Montague]

I wouldn't say it's completely arbitrary. There's some foundation there, and they're basing it off each other. You have to start measuring things somewhere, and basing it off some flawed measurement of the earth beats basing it off some king's foot or penis. The imperial system is a lot harder, while at least for metric, they put an effort to keep it base 10 and easy to convert to each other.

I've thought Celsius was the easiest to get right. 0 is freezing point, 100 is boiling point. Kelvin uses the same increments of Celsius, just that they set their 0 point at the minimum physically possible.

Imperial isn't that bad, most of the ones in modern use are reasonable. Tends to use numbers that divide evenly ex: 1 gallon = 2 quarts = 8 pints = 128 fluid ounces. 1 yard = 3 feet = 36 inches. Using 10 as a base number for everything isn't as flexible without using fractions and 3-digit numbers all the time. Then you have metric units which are never used because of irrelevance, like decimeters and whatnot.

 I'm not going to say barelycorns and stones make a ton of sense, but I think Imperial works better for everyday, human-scale measurements then metric does, which is probably why it's still in use.

Really I think both systems have their flaws and should probably both be ditched in favor of a new system. Something based off real physical properties and uses a base 8 or base 12 scale.

[Starver]

Ah now, that's a new point entirely...  Base eight or twelve?  What's your thinking with that?

I'm guessing that your base eight idea is to be binary compatible (albeit that it's a 3-bit 'byte' (or whatever's one less than a nybble/whatever), which is a strange number that makes memory referencing a strange art, where 2^(2^n) would be a better choice[1], such that hexadecimal is probably the better choice.

Base twelve you're going for much as per the ancients who liked to easily divide by 2, 3, 4 (also 6), right?  Admirable.

Of course, we're going into the realms of switching whole thinking-systems, whatever way.  Not just a new scale, but a new order of magnitude.  Of course, in computers we can do anything (base negative-pi, anyone? ), but that's something else.

Anyway... real physical properties?  Best bet is, e.g. a mass that is a nice round number of hydrogen atoms (easily agreed by all races throughout the universe, taking isotope concentrations into account).  Oh, but "nice round number" 1x10^?.  Or some power of 2, 4, 8, 12, 16, 42, 60, 8128?  Somewhere there's arbitrariness, and who knows what number of pseudopod-endings our galactic neighbours generally count on..!


[1] And ideally 'n' being itself a 2^? value, recursively, until you reach 2^1 (and thus 2^(2^0)).