• Norgur@kbin.social
      link
      fedilink
      arrow-up
      8
      arrow-down
      2
      ·
      1 year ago

      Thinking about it… Isn’t that exactly what the Celsius scale does just with reliable definitions about what “cold” and “HOT” mean?

      Shower water with 38°C is hot, a bowl of rice at 38°C/100F is decidedly not “HOT”. So the perceived convenience of the Fahrenheit scale is not applicable to everything, is it? How is it convenient then?

      • CherenkovBlue@iusearchlinux.fyi
        link
        fedilink
        arrow-up
        8
        ·
        1 year ago

        O F is the freezing temperature of a saturated brine solution, while 100 F was the body temperature of a human. Yes, body temperature has been revised a bit, but the two points were chosen as stable points that anyone could access that would generally be unchanged by pressure changes, etc. Human homeostasis is quite good at keeping a temperature in a narrow range. Also, boiling is massively affected by air pressure. At 5000’ elevation, boiling is approximately 202 F and continues to get lower as altitude increases. Lots of people live at higher altitudes. (Hi! I am one of them !)

        • inspired@kbin.social
          link
          fedilink
          arrow-up
          2
          ·
          1 year ago

          This is really interesting and I think there is a lot of support for the body temperature point. I was curious about whether the method of deriving 0F is insensitive to pressure changes and I can’t find any evidence of that. But I don’t know enough about chemistry or physics myself. Do you know, or have any details on where you learned this?

          • CherenkovBlue@iusearchlinux.fyi
            link
            fedilink
            arrow-up
            1
            ·
            edit-2
            1 year ago

            So I was a little off on the temperature chosen for the body, but the Wikipedia page has some good details: https://en.m.wikipedia.org/wiki/Fahrenheit

            Re: freezing temperature of brine and pressure sensitivity, of course it is sensitive but we are talking about MPa-GPa of pressure, way beyond small pressure changes due to changes in altitude. You can get started by looking at physical chemistry of solutions if you are interested! A good place to start is “freezing point depression” and “boiling point elevation” of solutions. Also, single component phase diagrams: here it is for water.

      • yata@sh.itjust.works
        link
        fedilink
        arrow-up
        1
        ·
        edit-2
        1 year ago

        It is convenient because they are used to it. That is all there is to it, and peace be to that.

        It only becomes silly when they begin to claim that F is better for “human temperature”, because again it all comes down to what you are used to and celsius is just as convenient if you are used to that.

    • sudo@lemmy.fmhy.ml
      link
      fedilink
      arrow-up
      5
      ·
      edit-2
      1 year ago

      As an American this is how I interpret Celsius

      • 100 is boiling
      • 50 is you’re gonna die from heat exhaustion eventually
      • 40 is hot
      • 30 is a little warm
      • 20 is a little cool
      • 10 is cold
      • 0 is freezing
        • sudo@lemmy.fmhy.ml
          link
          fedilink
          arrow-up
          1
          ·
          1 year ago

          Yeah I’m down by 30° latitude. I’d be inclined to agree with you back when I lived north of 40°

      • Terrasque@infosec.pub
        link
        fedilink
        arrow-up
        6
        ·
        1 year ago

        As a Norwegian:

        • 100 is boiling
        • 40 is we all gonna die
        • 30 is hot
        • 20 is a little warm
        • 10 is a little cool
        • 0 is cold
        • -5 is maybe time for a jacket
        • -10 shit, it’s freezingly cold outside!
        • -15 I’ll stay indoors if I can
      • CodeInvasion@sh.itjust.works
        link
        fedilink
        arrow-up
        5
        ·
        edit-2
        1 year ago

        I regularly convert between the two just by remembering the conversions for 10, 20, 30, and 40. It’s actually pretty easy.

        • 0C is 32F (of course)
        • 10C is 50F
        • 20C is 68F (a cool room temp)
        • 30C is 86F (reciprocal of 20)
        • 40C is 104F

        If you ever forget what one of them is, then just add 18F for every 10C from the last one you remember.

      • DaedalistKraken
        link
        fedilink
        arrow-up
        2
        ·
        1 year ago

        This is actually great, I’ve never found a good way to remember Celsius temperatures. I might go closer to Terrasque’s scale though, 30 is definitely hot where I am.

      • Buffalox@lemmy.world
        link
        fedilink
        arrow-up
        3
        arrow-down
        2
        ·
        edit-2
        1 year ago

        Metric:

        10 mm = 1cm, 100 cm = 1m, 1000 mm = 1m, 1000m = 1 km.

        1 cm3 water = 1 gram

        1 Watt heats 1 gram of water 1 C°

        1 dm3 water = liter = 1 kg

        1 m3 = 1000 kg = 1 tonne

        Imperial:

        1 mile = ?? yards = ?? feet = ?? inches

        1 ton = ?? stone = ??punds = ?? oz = ?? grain

        1 Galon = ?? pints = ?? fluid ounce

        1 inch3 = ?? grain = ?? power to heat ?? fahrenheit

        There is no system to any of these, they are unscientific and impractical.

        How does Imperial still have any relevance as a measurement system?

          • Buffalox@lemmy.world
            link
            fedilink
            arrow-up
            1
            arrow-down
            1
            ·
            1 year ago

            Yes, you could say Imperial is easier, because you’d never calculate anything in your head, you ask Google.

            But how did that even work before we had Internet?

            • AnUnusualRelic@lemmy.world
              link
              fedilink
              arrow-up
              2
              arrow-down
              1
              ·
              edit-2
              1 year ago

              I suppose they had little booklets. A bit like the logarithmic tables that people kept for complicated calculations. Maybe they were issued on the first day of school or something. People would keep them all their life and look at them surreptitiously whenever they had to convert units.