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Localization Failure: Temperature Is Hard

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Re: Localization Failure: Temperature Is Hard

#101

Post by throwaway290 »

mr_mitm wrote: post #14
mikewarot wrote: post #5

If you want "twice as hot" to be meaningful, you have to use an absolute scale, either Kelvin or Rankine. (1 K = 1.8 °R) Doubling absolute temperature doubles the pressure (at constant volume) or volume (at constant pressure) of an ideal gas. This gets really important when it comes to compressing and expanding air and other gasses. Room temperature is approximately 293 K, twice that is 586 K / 595 °F / 313 °C. Hotte…

You don't need an absolute scale, you just need a sensible origin. I suggest taking human perception into account. When talking about the weather or everyday objects, one could argue that the border between "hot" and "cold" is somewhere at room temperature, so around 21°C. At that temperature, it's neither hot or cold. If it's 30°C, it's 9°C of "hotness", so 39°C would be twice as hot. I don't know if it feels twice…

How given temperature feels depends on humidity, airflow, local culture, individual human and specific condition of that human (sitting/moving/sleeping, caffeinated, just ate a meal, bored, enthusiastic).

- I know someone who wears a puffy jacket indoors if it's 24 degrees.

- You will find sitting in 20 degrees with 88% humidity much more miserable than 20 degrees and 33% humidity.

- 42deg with 20% humidity and slight breeze is fine, 38deg with 90% humidity can make you pass out in minutes if you need to walk anywhere in the sun.

Re: Localization Failure: Temperature Is Hard

#102

Post by School-Cotton »

rendaw wrote: post #97
School-Cotton wrote: post #63

Earlier quoted context omitted.

> Maybe it helps to push for Murica to finally adapt SI units. Nitpick: Celsius is not an SI unit. Answering the substantive point: it’d be nice if we switched to SI units (plus Celsius); personally my phone is already set to display those and I wish we’d join the rest of the world and do standard stuff. However, I think it’s extremely unlikely to ever happen. The deadlocked US political system makes it impossible to…

Per wikipedia > The degree Celsius is ... one of two temperature scales used in the International System of Units (SI), the other being the Kelvin scale. Edit: To expand, within SI Celsius is defined as a derived unit, and Kelvin is a base unit.

It seems you’re absolutely right and my nitpick was not correct.

Re: Localization Failure: Temperature Is Hard

#103

Post by sgarland »

dontlaugh wrote: post #100
shalmanese wrote: post #99

Earlier quoted context omitted.

How do frameworks deal with the miles/gallon -> liters/100km conversion? I've always found that one particularly interesting as one that requires inverting the units also.

It’s even worse, the US has different gallons from the rest of the world.

To be fair, imperial gallons are based on 10 lbs of water (with very specific atmospheric conditions), which while a nice round number, isn’t as easy to recreate as the U.S. gallon, which is 231 cubic inches.

Of course, liters make way more sense than either of these.

Re: Localization Failure: Temperature Is Hard

#104

Post by trepanne »

Karellen wrote: post #95
psychoslave wrote: post #7

Earlier quoted context omitted.

Why do we use degrees for other temperatures by the way? Is that related to some kind of absolute vs relative metric? (Kelvin, I guess, is based on absolute zero as a reference point, doesn't it?) Incidentally, why is the degree immune to disappearance in division unlike all other units? That is, if I divide a distance (m) by a speed (m/s) I get a duration (s). From sheer memory, degree doesn't work like that. Any cl…

The root of the word "degree" basically means "units" or "subdivisions" or "measurements" or "amounts". We didn't really have a better word for units of temperature, as "Celsiuses" or "Farhenheits" didn't become a thing, so "degrees (of) Celsius" or "degrees (of) Fahrenheit" is kind of what we're left with. We could have chosen to say "degrees (of) kelvin", but we decided to go with "kelvins" (like "meters" or "secon…

> That said, I can't think of a situation where degrees (of temperature?) would disappear in a mathematical operation.

I regret that the decades that have elapsed since I studied physical chemistry & thermodynamics don’t permit me to make a proper answer, but if you want this to make sense I believe you should look many orders of magnitude smaller- Boltzman’s derivation of the ideal gas law from Newtonian mechanics using statistical methods.

Temperature is basically thermal density; it’s not really a fundamental unit. Chemical engineers use steam tables all the time to convert temperature to heat or other quantities.

Re: Localization Failure: Temperature Is Hard

#105

Post by grey_earthling »

A useful habit (which I think I picked up while studying physics at sixth-form) is to describe temperature intervals in “Celsius degrees” (and specific temperatures in “degrees Celsius”).

So a temperature of 43 degrees Celsius is 18 Celsius degrees hotter than 25 degrees Celsius.

32 Fahrenheit degrees are equivalent to 18 Celsius degrees; but 32 degrees Fahrenheit is equivalent to 0 degrees Celsius.

(There's no real need to do this when using absolute units, but I'd still pluralise the interval and not the absolute value: 316 kelvin is 25 kelvins hotter than 291 kelvin.)

Re: Localization Failure: Temperature Is Hard

#106

Post by Kim_Bruning »

odiroot wrote: post #48
matsemann wrote: post #16

A bit related, but I hate how many errors I get because I want my system language to be English instead of my native language (Norwegian) on my laptop, phone etc. Because I don't want a badly translated experience. However, I still want units in meters, Celsius, dates written sensibly, time in 24h format etc. But not all apps understand this, which is quite annoying. It's like they only look at the language and make…

I usually set my system to English / Ireland. I get English but with normal units and € as a default currency.

I think en_IE is a rather undersold/underpromoted "international/european english" locale that more people should know about!

Re: Localization Failure: Temperature Is Hard

#107

Post by thfuran »

lynguist wrote: post #40
mikewarot wrote: post #5

If you want "twice as hot" to be meaningful, you have to use an absolute scale, either Kelvin or Rankine. (1 K = 1.8 °R) Doubling absolute temperature doubles the pressure (at constant volume) or volume (at constant pressure) of an ideal gas. This gets really important when it comes to compressing and expanding air and other gasses. Room temperature is approximately 293 K, twice that is 586 K / 595 °F / 313 °C. Hotte…

Twice as hot is also useful in Celsius. For every increase of 10C chemical reactions happen twice as fast, it will literally, thermodynamically be twice as hot. Which will probably even match your subjective feeling. Celsius scales thermodynamically logarithmically. You can’t just double the numbers. (The same with sound etc.)

>For every increase of 10C chemical reactions happen twice as fast

Except for the ones that go at different rates.

Re: Localization Failure: Temperature Is Hard

#108

Post by Joker_vD »

mr_mitm wrote: post #14
mikewarot wrote: post #5

If you want "twice as hot" to be meaningful, you have to use an absolute scale, either Kelvin or Rankine. (1 K = 1.8 °R) Doubling absolute temperature doubles the pressure (at constant volume) or volume (at constant pressure) of an ideal gas. This gets really important when it comes to compressing and expanding air and other gasses. Room temperature is approximately 293 K, twice that is 586 K / 595 °F / 313 °C. Hotte…

You don't need an absolute scale, you just need a sensible origin. I suggest taking human perception into account. When talking about the weather or everyday objects, one could argue that the border between "hot" and "cold" is somewhere at room temperature, so around 21°C. At that temperature, it's neither hot or cold. If it's 30°C, it's 9°C of "hotness", so 39°C would be twice as hot. I don't know if it feels twice…

Water-freezing temperature is an absolutely sensible zero. The difference between e.g. 2 °C and -2 °C is really quite obvious for the exposed skin: while it's merely "yeah, it's cold" feeling when it's above zero, it almost feel like the frost is biting, almost literally, when it's below zero.

Re: Localization Failure: Temperature Is Hard

#109

Post by avgcorrection »

eviks wrote: post #4
perilunar wrote: post #3

Hard? So is using the degree symbol apparently: not a single one in the whole article. (68F is not a temperature — it’s a seat number.) https://degreeswhat.com/?68

"To be fair", there is ASCII in the name

    68:degrees:F

Re: Localization Failure: Temperature Is Hard

#110

Post by daoboy »

The book Inventing Temperature by Hasok Chang is a wonderful account of how hard it has been to grapple with temperature scientifically.

My favorite anecdote is the scientist who carried arround and shook a bottle for two weeks to distill the water for experiments in finding when water boiled. When the water exploded after heating he found that not only did he not know when water boiled, but now he wasn't even sure what boiling was.

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