• dandelion@lemmy.blahaj.zone
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    2 months ago

    this feels like a potentially sincere attempt to recruit people into an anti-science conspiracy movement - this doesn’t really feel different than the kind of reasoning you see with moon landing denialists or flat earthers.

  • gandalf_der_12te@discuss.tchncs.de
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    2 months ago

    Enter vapor pressure:

    Basically water always evaporates if the air is completely dry, until the air contains a certain amount of water (measured in partial pressure, which is the part of the air pressure that is caused by water vapor). This partial pressure is temperature-dependent, so if you have 20°C (normal room temperature) you’re gonna have 23 mbar of water vapor partial pressure in the air. Source

    So water still evaporates at lower temperatures when the air is dry enough. It’s just that at 100°C (“boiling point of water”), that partial pressure of water vapor in the air increases to 1013 mbar which is equal to the total pressure of the air; In other words, at that temperature in equilibrium, the air is totally made up of water vapor and nothing else. If you increase the temperature above that, the water vapor partial pressure tries to still increase, which makes the total pressure go above normal air pressure, which causes a pressure gradient and causes the air to move with mechanical force, which you can use to make turbines spin.

    • Danitos@reddthat.com
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      2 months ago

      A more microoscopic explanation is due to Maxwell-Boltzmann distribution.

      First, you need to underestand temperature. The difference between cold and hot water is the average speed at which particles move, with hotter water’s particles moving faster.

      But this is just the average speed, it turns out that particle’s speed can be se en as a random variable, and they follow Maxwell-Boltzmann distribution:

      Maxwell-Boltzmann distribution

      So you have a small proportion of particles that move very fast, even in cold water. If some of those particles get (or collide with other particles near) to the “layer” of water that is on contact with the air, they will have enough energy to escape water’s superficial tension, thus going into the air and out of the water body. The higher the average speed of the particles, the faster this process will go. Finally, the rate at which this process happens also depends on the energy required to be able to leave the water body, which depends on factors like air pressure.

      • gandalf_der_12te@discuss.tchncs.de
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        2 months ago

        yeah i’ve of course heard about it and i’m studying physics myself rn so i’ll get to it.

        I simply haven’t taken the course on quantum physics yet so i don’t want to make bold claims here. I have yet to derive the classical phenomena from quantum physics myself.

        • Danitos@reddthat.com
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          2 months ago

          You won’t see this on a quantum mechanics class, but on my favorite one, statistichal mechanics.

    • Nindelofocho@lemmy.world
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      2 months ago

      Thank you ive always wondered about this but never wondered about it when I had the chance to look it up and now I know :)

  • WanderingThoughts@europe.pub
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    2 months ago

    The teacher was explaining about conducting and not conducting, and we had a battery with lamp thing to test on various objects. I of course had to test this on a pencil and discovered semi-conducting. That was a serious “not today” sigh from the teacher.

  • xep@discuss.online
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    2 months ago

    It’s interesting because very pure water without asperites can be heated above 100c at standard pressure at sea level without boiling. But once impurities are added to it it starts boiling vigorously!

    • fibojoly@sh.itjust.works
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      2 months ago

      Sounds like the same thing that happens at 0°C with very pure water that stays liquid, but shake it and bam! It insta-freezes.

      • Kellenved@sh.itjust.works
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        2 months ago

        Sometime water bottles display this trait in temps just below freezing. Liquid water in the bottle but break the seal and pop! Frozen

      • reptar@lemmy.world
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        2 months ago

        Doesn’t have to be pure for that! I’ve seen it happen with those cheap plastic sleeve popsicles. It’s kind of fun flicking them and watching the ice radiate through.

      • xep@discuss.online
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        2 months ago

        Imperfections in the surface of the container the water is in. Sorry, I intended to write ‘water in a container without asperites’!

        • HugeNerd@lemmy.ca
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          2 months ago

          Hm, still not sure what “asperites” are. You seem to be describing asperities.

      • Rain World: Slugcat Game@lemmy.world
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        1 month ago

        fun fact: asesprite used to be libre!
        fun fact: clippit was only created after microsoft was definitely evil (anticompetitive), might wanna consider changing your pfp!

        • thethunderwolf@lemmy.dbzer0.com
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          1 month ago

          fun fact: asesprite used to be libre!

          i knew that

          fun fact: clippit was only created after microsoft was definitely evil (anticompetitive), might wanna consider changing your pfp!

          are you aware of that louis rossman video? look up “why clippy profile picture”

  • DeathsEmbrace@lemmy.world
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    2 months ago

    Temperature is based on “average” kinetic energy so technically there are molecules with higher energy’s that are higher than the transition state and that’s why

  • Caveman@lemmy.world
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    2 months ago

    For fun I’m going to explain why. So air can hold some amount of water in it at any temperature. Water energy in form of heat is not evenly distributed so some molecules move faster than others, at the surface some move fast enough to escape the water and into the air. That’s called evaporation, boiling does however require 100°C.

    This also explains why humid weather affects evaporation (lower capacity to hold water in air) and at high humidity there’s an a similar chance of water being deposited to the body of water as water escaping which affects evaporation speed a lot.

    Honestly, I really like this quality of water, it would be super annoying to deal with otherwise.

  • Frostbeard@lemmy.world
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    2 months ago

    I had this question in a mid-term in physical chemistry 20 years ago. I can’t remember the details but it is driven by the entropy in the system. Along with the things other have said about changes right above the surface of the puffle.

  • J92@lemmy.world
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    2 months ago

    “Water can only fly when its a gas!!!” Words from losers that have never looked at the sky.