• deegeese@sopuli.xyz
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    9 months ago

    Because physics uses Kelvin for high temperatures, and electron volts for really high temperatures.

  • db2@lemmy.world
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    9 months ago

    Because kilodegrees sounds funny. But megadegrees really sounds volcano lair evil.

    • GrymEdm@lemmy.world
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      9 months ago

      Megadegrees sounds like something graduates from Trump University got for finishing a retreat. They are the highest quality degrees - so good they deserve to have their own name!

      Going back to temperature though, it would be odd-sounding to say the Sun can get as hot as 15 megadegrees at it’s core.

  • Treczoks@lemmy.world
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    9 months ago

    First of all, the °C is not the metric SI unit for temperature. K (Kelvin) is.

    Second, even with Kelvin, nearly all temperatures that matter for normal human issues happen to be below 4000K, usually way below that mark. And with most of those temperatures, about all digits usually count. A core body temperature of 310K or 313K makes a BIG difference for the person involved.

    • frezik@midwest.social
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      9 months ago

      Celsius is the SI unit of temperature. Kelvin is the SI unit of thermodynamic temperature. They’re both defined in SI.

    • Jojo@lemm.ee
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      9 months ago

      I’ve seen mK used numerous times, but I haven’t seen, like MK for internal temperatures of stars or things. I imagine because those are more “for fun” numbers while the precise temperatures in a low temperature physics lab are four technical purposes.

      • cynar@lemmy.world
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        9 months ago

        Celsius uses an arbitrary reference point (freezing point of water). Kelvin uses the same sized units, but is referenced from absolute zero. While this seems just as arbitrary, it actually makes some scientific calculations a lot easier.

        Basically, scientists have been working to slot the various base units together in a neat and orderly manner. Kelvin fits this far better than Celsius, and so became the baseline SI unit.

          • cynar@lemmy.world
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            9 months ago

            I fully agree with that. It’s also quite easy to shift between the 2. I just had the difference drilled into me way too much, at university.

          • ByteWizard@lemm.ee
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            9 months ago

            Fahrenheit is better for human-survivable temps.

            Fahrenheit:

            • 0° - Really cold
            • 50° - So-so
            • 100° - Really hot

            Celsius:

            • 0° - Cold
            • 50° - Extremely hot
            • 100° - Dead

            Kelvin:

            • 0° - Dead
            • 50° - Dead
            • 100° - Dead
            • ByteJunk@lemmy.world
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              9 months ago

              Some people seem to have this misconception that “0F cold 100F hot” is somehow an innate or intuitive concept for everyone. It’s not, brother, you just happen to be used to it. I have absolutely no idea if I should wear a coat with 62F or not, or for any other F temperature for that matter.

              At least 0C and 100C have very practical references that anyone can recognise, but what the hell even is 0F and 100F?

              Also, not sure why you’re trying to shoehorn 0-100F to 0-100C.

              When talking about weather, it’s going to be in a range like 0C (cold) / 20C (nice) / 40C (hot), which is equally arbitrary but probably more useful than 0F/50F/100F anyway depending on where you live: my neck of the woods goes to 0C in a harsh winter, and to 40C in the peak of summer.

              And do you use F for stuff like cooking? What purpose is 0F or 100F there?

              How about stuff like chemistry or physics? I remember formulas in C or K, occasionally having to add 273.5. Is F used, or you just use K/C and convert at the start?

  • viking
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    9 months ago

    Would just be confusing. Temperatures above a few hundred degrees have no place in most people’s daily lives, so that would be mostly for scientific notations, and scientists use Kelvin anyway for precision.

  • judooochp@lemmy.world
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    9 months ago

    [Edited because of weird auto-formatting. Edit 2 added more pedantry. Edit 3+ is because I lost the plot and had to bring it back.]

    Because the SI unit for temperature is the Kelvin, which has already been stated. It has also been mentioned that K and °C are the same but with different offsets. It has not been mentioned that °C is to K as Degrees Fahrenheit (°F) is to Rankine ( R). It would be similarly inappropriate to say “millidegrees Fahrenheit” or “kilofahrenheit”. I have no idea if mR or kR would be appropriate, though.

    I would offer that there are two ways to look at SI (“metric”) prefixes, and these can be thought of similarly with the multipliers they represent: as a prefix to the unit, by definition; or as a suffix to the value. Let me illustrate with an example.

    38,000 K could be expressed 38 kK, or “thirty-eight kiloKelvin”. It could also be spoken “thirty-eight thousand Kelvin” (or Kelvins, idfk). This isn’t normally important for the layperson, but suppose you have a temperature meter (and, literally, I do not mean “thermometer”) that has only 4 digits of resolution. 38.00 k (“38,00 k” for the Europeans?) would be how it reads out the value in question. This would be 38 kK, certainly, due to the position of the decimal.

    Now suppose that temperature meter read out in °C. 38.00 k °C would, in fact, denote “thirty-eight thousand degrees Celsius” for the reasons mentioned above.

    So, because Degrees Celsius is not an SI unit, in the technical sense…

    Btw, I have been explicitly using upper case letters when spelling out the units. This is incorrect. The symbols for SI (International System of Units) units should be capitalized when they respect a person (K, A). The names of the units should be all lower case because you are not naming the person, but the unit named after them (kelvin after Lord Kelvin, and ampere after Andre-Marie Ampere).

    Yeah, I know. I’m being pedantic. It’s literally my job. I really should be sleeping right now. Here’s a source: https://www.bipm.org/en/measurement-units/si-base-units

    • Carighan Maconar@lemmy.world
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      9 months ago

      There’s no way someone would use something as logical as “Millifahrenheit”.

      It’s be 143 Fahrenheit in a Blurgenfurl, 2 Blurgenfurl in a Whatjamagick and 19003 Whatjamagick in a Plenderboing.

      • judooochp@lemmy.world
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        9 months ago

        Lol. Nah, my brother woke me up in crisis to have a conversation in text instead of over the phone, so my wife left to sleep in her own bed in a huff, and I just started new meds …

  • BarqsHasBite@lemmy.ca
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    9 months ago

    Guess there’s not much need. Most of the prefixes used are 1000 (kilo, mega, etc.) or 1/1000 (milli, micro, etc). The tens and hundreds are a bit odd to use and imo shouldn’t be used. So there’s no need to use prefixes until you’re into Star temperatures or really extreme experiments.

  • Dave.@aussie.zone
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    9 months ago

    It’s really when you get into the thousands though that SI prefixes generally start to be used, you don’t see deca or hecto used that often. It’s mainly because we’re usually happy keeping three digits of precision in general conversation (185 degrees C, 250 metres, etc). After that we get a bit sloppy and start rounding, and that’s where kilo comes in and we start talking about “1.25 kilometres” and such.

    Add in the fact that people rarely need to describe temperatures higher than 1000 degrees C with any precision, (they’ll just round to hundreds/thousands/millions usually) and that’s why SI units feel weird with temperature.

  • Artyom@lemm.ee
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    9 months ago

    Interestingly, I hear people use terms like millikelvin and microkelvin often enough, but never kilokelvin. In fact, there are some hilariously impractical ways to avoid large scientific notation for Kelvin. There’s T4, which is the temperature in kelvin divided by 10^4, and there’s electron volts, which is almost the same value, but preferred by different fields.

  • BehindTheBarrier@programming.dev
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    9 months ago

    It’s probably more common that scientific notation is used. So 3.2 *10^4 or simply 3.2e4. From the little physics I had, you often used kilometers instead of something like megameters. Or used just lightyears when you got on a big enough scale.