When the great pyramids were being built there was still woolly mammoths walking the earth.

  • IamMoonPie@lemmy.world
    link
    fedilink
    arrow-up
    5
    ·
    3 hours ago

    Humans can’t feel wet, what we’re actually feeling is cold. It’s why when you have a cold patch on a blanket or carpet you can’t quite figure out if it’s wet or not.

    • wolframhydroxide@sh.itjust.works
      link
      fedilink
      arrow-up
      2
      ·
      edit-2
      15 minutes ago

      It’s actually an even greater level of abstraction: we feel the rate of heat flow through our skin. This is (kind-of) why plastic feels warmer than metal. Colder things don’t feel colder because they are colder. Colder things feel colder because they more efficiently sap heat from our skin. Wet things feel colder because water and other highly conductive fluids which have wet the skin (and are thus in direct contact with it) are much more efficient in removing heat, thus feeling colder. This is the twofold reason why oil doesn’t feel as cold as water: it has significantly worse heat conductivity, and it doesn’t readily evaporate (as evaporation is a highly endothermic process, sapping heat even more efficiently than a conductive liquid on its own.)

      • HexesofVexes@lemmy.world
        link
        fedilink
        arrow-up
        1
        ·
        1 hour ago

        Let $\mu(x)=0$ if $\exists y<x\mu(y)=0$ or $x$ is the 20 millionth prime. $\mu(x)=\mu(x+1)+1$ otherwise. The elements of the sequence only become defined once the 20 millionth prime is found; till then they’ve yet to be constructed.

        Bonus: The sequence $\nu$ is defined as follows.

        Let $\nu(x)=0$ if $\exists y\leq x\mu(y)$ is perfect. $\nu(x)=\nu(x+1)+1$ otherwise.

        We’re not sure if this is a sequence, even though it is algorithmically definable. Its existence relies on the existence of an odd perfect number.

  • SirEDCaLot@lemmy.today
    link
    fedilink
    arrow-up
    7
    arrow-down
    1
    ·
    7 hours ago

    Everyone knows you jump in the pool in summer, smell the chlorine, and know the water is clean, right?

    Fun fact- chlorine dissolved in pool water at the usual sanitation levels has almost no perceptible smell or taste.
    HOWEVER, when chlorine binds with certain organic substances, especially ammonia (from the urea in sweat and urine), the result is chloramine which has a significant chlorine-y smell. Chloramine has essentially no disinfecting properties.

    So when you go to the public pool and get a whiff of chlorine and think ‘man they’re using a lot of chlorine today’, no, it probably means someone peed in the pool.

    You’re welcome :)

    • Professorozone@lemmy.world
      link
      fedilink
      arrow-up
      6
      ·
      6 hours ago

      Ok, but why then when you open a bottle of bleach or container of chlorine pellets, does it smell like chlorine. Do they add the piss ahead of time?

      • adarza@lemmy.ca
        link
        fedilink
        arrow-up
        2
        ·
        2 hours ago

        take all but 1.5mL out of that gallon jug of household bleach, then fill it back up with water. that’s roughly the concentration of chlorine in a swimming pool.

      • SirEDCaLot@lemmy.today
        link
        fedilink
        arrow-up
        2
        ·
        4 hours ago

        That’s pure chlorine, much higher concentration. At the concentrations of pool chlorination there’s essentially no smell.

  • whoxtank28@lemmy.world
    link
    fedilink
    English
    arrow-up
    12
    ·
    9 hours ago

    There is no thru line from mouth to urethra. You drink water, it gets absorbed into your blood, your urinary system filters excess water and waste, you pee it out. Your pee is filtered blood, the only thru line for water to take from your mouth is your ass. I understood that when it was taught, but I didn’t really think about it…

  • agent_nycto@lemmy.world
    link
    fedilink
    arrow-up
    5
    ·
    9 hours ago

    The people who got anime to take off in the US are the same people who started the furry fandom.

    The Superman symbol was based off of the symbol for a sci fi fan club.

    Conventions, and sci fi as we know it, are because of one electronics magazine.

  • Bytemeister@lemmy.world
    link
    fedilink
    English
    arrow-up
    7
    ·
    9 hours ago

    Useless knowledge.

    When playing Mechwarrior 2 on a Windows 2000 system, make sure to change your video mode to 32bit color.

    I’ll throw in a useful tip too!

    You can buy USB foot switches for your computer and assign keystrokes and other functions to them.

    Almost feels like cheating when you are playing a tactical shooter and can lean left or right and strafe on demand without crossing any controls. Having microphone activation, map, inventory, or any number of misc actions boud to a foot pedal makes a huge difference in your ability to play a game.

    • Captain Aggravated@sh.itjust.works
      link
      fedilink
      English
      arrow-up
      4
      ·
      7 hours ago

      Further knowledge about Mechwarrior 2: 31st century combat:

      At various stages in the campaigns, you’ll face off against Elementals, escort a Tarantula, and fight a Battlemaster. Through cheat codes, you can add these to the mech lab and play in them in the “Trial of Grievance” free play mode. The Elemental works fine, it functions as a tiny mech, the Tarantula works mostly correctly, but it isn’t 4-legged. It looks like it is but the front two legs are legally arms, they can be blown off and it works fine. Trying to select the Battlemaster in the mech lab will immediately crash the game.

      Cheat codes for Mechwarrior 2 were the very, very first thing I searched the internet for.

  • Goldmage263@sh.itjust.works
    link
    fedilink
    arrow-up
    4
    ·
    9 hours ago

    The gorgeous Lunar Moth exits the chrysilys fully formed, without a mouth or other structure for the intake of nutrients. It only exists to fly and breed at that point and expires around a week later.

  • Jankatarch@lemmy.world
    link
    fedilink
    arrow-up
    2
    ·
    edit-2
    7 hours ago

    The guy who did localization for the Zambak magazine’s Turkish translation of “the alice in wonderland” has the cool birthday January 1st, 1969.

    (Might’ve been another magazine, could not find a picture online)

  • Krudler@lemmy.world
    link
    fedilink
    English
    arrow-up
    28
    ·
    19 hours ago

    With vanishingly rare exception, addicts choose the mood altering substance that is closest to what the medically accepted treatment for their underlying disorder(s) would be.

    People who are addicted to alcohol, without exception, have an underlying anxiety disorder.

    People with ADHD and similar brain functioning tend to choose amphetamines.

    The list goes on and it gets very complicated, because most mood altering substances have multiple effects, and most people have a blend of underlying issues. But the point is, there is a very noteworthy observation there, I feel.

    I feel qualified to say this as myself I am 11 years sober and have worked in the field of addiction for 8 years and I’m formally educated.

  • Captain Aggravated@sh.itjust.works
    link
    fedilink
    English
    arrow-up
    29
    ·
    20 hours ago

    The Mission Impossible theme, you know, the “Dun! Dun! DADA! Dun! Dun! Duhduh!” one, written in 5/4 time? That’s supposed to spell MI for Mission: Impossible, in Morse code. --.. dash dash dot dot, MI. The first two notes are dotted quarter notes, 1.5 beats each for a total of 3 beats, then two quarter notes for each dot, total of 2 beats, grand total of 5 beats per measure. 5/4 time.

    FIND A PRACTICAL USE FOR THAT SHIT.

    • Underwaterbob@sh.itjust.works
      link
      fedilink
      arrow-up
      8
      ·
      edit-2
      14 hours ago

      Hey! Same for Rush’s YYZ. The morse code for Y-Y-Z (the airport code for the Toronto airport where the band no doubt spent a lot of time) is --.- --.- --… which is a rhythmic motif that appears a bunch in the song in some ungodly meter I don’t care to look up right now.

      • Captain Aggravated@sh.itjust.works
        link
        fedilink
        English
        arrow-up
        2
        ·
        7 hours ago

        So, I don’t know if it did it on your end, the reason why I put my morse code in a code block is it expanded the two dots into three. Don’t know if it does it on all UIs but on my end it made your Z into dash dash dot dot dot.

        He says, as if it matters.