• Zerthax@reddthat.com
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    8 hours ago

    Reminds me of a time one of my friends was happy that it was going to warm up and said something like “it’s going to be twice as warm tomorrow”. It was going from maybe 20F to 40F or something.

    That led to an interesting discussion.

  • 🐋 Color 🔱 ♀@lemm.ee
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    15 hours ago

    30°C is 303 Kelvin. Half of that is 151 Kelvin, which translates into a fairly mild -122°C!

    Takes out hockey stick

    • Eiri@lemmy.ca
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      7 hours ago

      Wait, does it? Are joules in thermal energy per kelvin a purely linear relationship?

      • TonyTonyChopper@mander.xyz
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        4 hours ago

        Fun fact: gas pressure changes linearly with temperature. If you make one of these plots at mild conditions you can extraplate the line down to zero pressure and measure where absolute zero temperature is

      • Verat
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        4 hours ago

        For the most part, it varies by material and state of matter, but assuming the chemical composition doesnt change and no material changes phase, then it is pretty close to linear in most materials.

  • frezik@midwest.social
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    14 hours ago

    This knowledge comes in handy with marketing BS around CPU coolers. If an aftermarket cooler gets a CPU to 35C when the stock cooler is at 70C, marketing will sometimes claim it cut temperatures in half.

    • jws_shadotak
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      7 hours ago

      I mean… that’s literally half though

      edit: I am not a science man and I am in over my head in this argument

      • FiskFisk33@startrek.website
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        5 hours ago

        to make the argument even simpler, that phrase wouldn’t even mean the same thing to an english person as it would to an american.

        In fahrenheit those temps would convert to 95f and 158f.

      • frezik@midwest.social
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        7 hours ago

        If you convert those temperatures to Kelvin, they become 308K and 343K. Since Kelvin is absolute and we’re measuring the same material, this tells you how much more thermal energy is there and their actual proportion to each other.

        • jws_shadotak
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          6 hours ago

          thanks, this makes a lot more sense.

          That being said, 70C down to 35C is a huge difference, relative to the temperature ranges we live in

      • chiliedogg@lemmy.world
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        8 hours ago

        But it’s not.

        Celsius and Faernheit are interval scales, not rational scales. The absolute change from one number to the next is consistent, but since you can go into the negatives, 1 is not double 2.

        Kelvin and Rankine are rational because they use an absolute zero.

  • taiyang@lemmy.world
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    13 hours ago

    I use this as an example for interval vs ratio; you can’t halve Celsius because it’s an interval scale where zero is arbitrary. Kelvin is ratio as it has an absolute zero-- you very much can halve it and doom near the entire planet next summer

      • LostXOR@fedia.io
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        11 hours ago

        How so? Absolute zero is the coldest possible temperature, it’s physically impossible for an object to be colder. Saying that’s arbitrary is like saying it’s arbitrary to define 0 m/s as not moving.

        • Telodzrum@lemmy.world
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          11 hours ago

          It’s still assuming a scale. It’s actually worse because the scale is implied by context.

          • stembolts@programming.dev
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            7 hours ago

            The context of… reading the fabric of the universe?

            You’re right, that is totally irrelevant to… a physicist.

            I see you’re trolling, so I look forward to your condescending response, but to be successfully condescending you have to be at least somewhat convincing in displaying intelligence, if you can manage that then this whole argumentative act will go much better and people will get much angrier.

            TLDR, Try the same troll tactic but with less incompetence for better results.

          • GBU_28@lemm.ee
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            10 hours ago

            Zero kelvin is very contextually useful. Put very simply it literally relates to the motion of atoms. At zero, they move zero.

          • xthexder@l.sw0.com
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            10 hours ago

            What? What context? The scale is the same as Celsius which is derived from the properties of water. And 0K is when there is absolutely no heat energy in the thing being measured. There is no context where this is not the case.

            • Telodzrum@lemmy.world
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              10 hours ago

              The one where a human is speaking in English and referring to a season and the temperature is more than significant context. I hope this helped you; it seems that you’re one of those people who lack the capacity to infer from available data.

              • xthexder@l.sw0.com
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                9 hours ago

                People don’t use Kelvin when referring to seasons. Sure, there’s plenty of ambiguity if someone says it’s 32° out without specifying the units, and you can infer from context, but that has nothing to do with Kelvin starting at absolute zero. Saying “degrees” immediately rules out Kelvin as a unit.

  • RustyNova@lemmy.world
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    3 hours ago

    Granted. Celsius now range from 0 to 50

    Edit: … or whatever unit you prefer. It’s still the same

    • ArtieShaw@fedia.io
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      14 hours ago

      I think it’s fairly well known that there are no good genies. But otherwise, true.

        • ArtieShaw@fedia.io
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          14 hours ago

          I was kind of thinking along the same lines. But to be truly ironclad, would you need a genie lawyer? Like not a lawyer who specialized in Genie Law, but an actual genie?

          • skulblaka
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            11 hours ago

            This is why I hire my attorneys from Avernus. Don’t nobody got lawyers like Hell has lawyers. If you’re trying to pull one over on a genie, you’re going to need either devils or fae. And the devils are more likely to respect their contract, including any loopholes you manage to find in it.

            • CrazyLikeGollum@lemmy.world
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              2 hours ago

              Considering making a wish on a shooting star? Been granted a wish scroll by an obnoxious DM? Give a lamp a handjob only for it ejaculate a genie? Then you need the services of Nine Hells Legal! Our prestigious law firm can draft up an ironclad wish for all your mortal needs! No loopholes guaranteed or your soul back.

              All fees to be paid in souls. Retainer fees are nonrefundable. The souls of the sacrificed and those otherwise deemed to fall within the purview of Hell are nonrefundable. “Nine Hells Legal” is a wholly owned trademark of Sir Asmodeus, esq. The archduke of the Nine Hells.
        • BallsandBayonets@lemmings.world
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          11 hours ago

          First wish, a lawyer who specializes in genie law. Unfortunately, the lawyer draws up a contract that screws you out of most of your wishes, not because of the genie’s influence, but because they’re a lawyer.

        • not_woody_shaw@lemmy.world
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          5 hours ago

          It’s a room made from platinum-iridium, and kept in a triple-locked vault at the International Bureau of Weights and Measures in France.

          • grozzle@lemm.ee
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            3 hours ago

            unfortunately, opening the door changes the temperature, so in practice instruments are calibrated from copies of the room built at other metrology institutions around the world.

    • hsdkfr734r@feddit.nl
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      13 hours ago

      The indoor temperature is always at room temperature and vice versa. It’s not constant though.

  • usualsuspect191@lemmy.ca
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    16 hours ago

    Is the temperature scale directly proportional to the heat energy? I think the amount of energy needed to raise water by 1 degree is the same no matter the starting temperature for example. Is 100°K double the heat energy of 50°K?

    • Contravariant@lemmy.world
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      12 hours ago

      Well at some point you encounter a phase change, which complicates things, but mostly the heat capacity (how much energy it takes to raise the temperature) is fairly constant. In an ideal gas it is exactly constant, but that is a bit of an approximation, even if it works quite well for most gases.

    • Chronographs@lemmy.zip
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      16 hours ago

      Kelvin doesn’t have degrees btw you just say 50K or 100K because it’s an absolute temperature scale as opposed to an arbitrary or relative one like Fahrenheit or Celsius. I’d expect that the energy would be double though that’s more of a feeling.

      • stebo@lemmy.dbzer0.com
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        9 hours ago

        As long as the mixture of the substance remains constant and there are no phase changes, heat energy and temperature are linear and half the heat energy is half the temperature. In reality this only works for solids because otherwise, halving the heat energy would definitely involve phase changes.

    • marcos@lemmy.world
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      16 hours ago

      That wish just condenses the atmosphere of half of the planet for half of the time. How do you like your puddles of liquid oxygen now?

    • bdonvr@thelemmy.club
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      14 hours ago

      Let’s say the summer average is 30⁰C or 303.15 Kelvin

      The absolute coldest possible temperature is -273.15⁰C, or 0K.

      Halfway between absolute zero and 30⁰C/303.15K is somewhere around -121⁰C/152K

      So if it were half as hot in the summer, it would be colder than ever recorded on earth.

      • frezik@midwest.social
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        13 hours ago

        In short, you don’t want to use a temperature scale with an arbitrary starting point for doing calculations like this. The freezing point of water is no more or less arbitrary than the freezing point of oxygen or sodium or anything else. It’s just one that’s somewhat useful for everyday use. When handling calculations for multiplying temperature, you want an absolute scale like Kelvin.

        Or Rankine if you’re that kind of pervert.

          • Bumblefumble@lemm.ee
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            11 hours ago

            0 K is like when there is 0 heat basically, while celsius isn’t. Imagine a unit for distance called “goob” where 0 goobs is 100 m and 1 goob is 115 m. In that case the goob unit would behave differently than a meter when you multiply and divide because 0 of the units don’t actually correspond to “nothing” in a physical sense. That’s exactly how the Celsius scale is, with zero being placed somewhere arbitrarily, not at a physical zero.

        • yetiftw@lemmy.world
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          12 hours ago

          absolute scales are still arbitrary. you would probably want to use a scale that measures “perceived heat” which is different than average kinetic energy

          • KairuByte@lemmy.dbzer0.com
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            3 hours ago

            Kelvin is just our word for it, but that is the point of “no heat”. It isn’t arbitrary, there is no “negative kelvin” just like you cannot make something colder than absolute zero.

            So if you take the difference between “coldest possible temp” and “average summer temp”, then slice it in half, you’re getting temperatures that would kill most life on earth.