• Echo Dot@feddit.uk
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    7 hours ago

    If the day started at 1:00 then by the second hour you would be at 2:00, even though only 1 hour has passed. Effectively the day starts at 0. In fact in 24-hour time that is how it’s depicted, 00:00 with midday being depicted as 12:00, so it isn’t confusing

  • teslasaur@lemmy.world
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    8 hours ago

    It’s the same logic that was used by ancient astronomers to arrive at 360 degrees for a full revolution.

    The math is easier if you have to do it by hand.

      • Hobo@lemmy.world
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        5 hours ago

        It’s also the one advantage Imperial has over metric. It’s easier to do mental math in a lot of cases in base 12 rather than base 10.

        Now excuse me while I bar my windows and doors from the mobs of angry people that show every time I point this out.

        • frezik@midwest.social
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          2 hours ago

          Let me jump in until the mobs show up. “Noooooo, it’s just what you’re used to lalala. When is dividing by thirds ever useful, anyway?”.

          I’ve also found that if you make this point without any reference to metric vs imperial, people tend to accept it.

        • ultracritical@lemmy.world
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          4 hours ago

          Only really counts for feet and inches. But yes, having your base unit be divisible by halves, thirds, quarters, sixths, and twelths with whole numbers of sub units is highly useful when fabricating objects when you don’t have access to modern tooling and supplies. In fact I would argue base 12 is the superior numerical system that was abandoned for metric and we have lost something in the meantime. Though Jan Misali might disagree with his love for sexinal.

          Imperial units do have another advantage to this day, though. When talking about machining bolts and threads Imperial use threads per inch or threads per unit length while metric uses the pitch of the thread, so mm in-between threads. This decision means that when machining imperial nuts and bolts we by default pick whole numbers of threads per inch which due to the circular nature of lathes means that a simple clock dial can keep the lead screw synchronised with the head. Since metric uses pitch we pick numbers like 1.25mm pitch which does not always synchronous well with the lead screw and head and requires some odd gear ratios to cut specific threads.

  • ParadoxSeahorse@lemmy.world
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    11 hours ago

    Well it’s because noon means nine because the day starts at six o’ clock, so three is noon, but we use it to mean twelve which is closer to midday, obviously

  • PieMePlenty@lemmy.world
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    11 hours ago

    Hour hand -> hour = n
    Minute hand -> minute = n * 5
    It makes sense, there’s just an algorithm attached to each pointer.

    Hour -> 3 = 3
    Minute -> 3 = 3 * 5 = 15

  • ssfckdt@lemmy.blahaj.zone
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    16 hours ago

    Somebody never had a clock with roman numerals and it shows

    I remember getting into an argument with a grade school teacher over IIII because most such clocks put that for 4 instead of IV because of some fuckin reason

    • Opisek@lemmy.world
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      12 hours ago

      I despise these so so much. IIII was historically NEVER correct. Some doofus decided to put that on a clock because it looks more symmetrical with the VIII on the other side. Terrible reasoning.

      • mhague@lemmy.world
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        4 hours ago

        IIII was the way Romans usually wrote 4. It’s associated with simplicity / illiteracy. But also depended on era, region, intended audience, or practicality. I think the most famous example is the coliseum using LIIII.

        There’s still variation even now; standardization is relatively new, and it’s not common knowledge. And dates… it’s like every 50-100 years people decided to write them differently.

        • naticus@lemmy.world
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          14 hours ago

          Yeah I looked it up and saw it is a thing, and it’s interesting. I wonder if the clock I’m thinking of was just a really cheap one that was labeled as you’d expect based on Roman numerals or whether some just didn’t follow it.

      • rumba@lemmy.zip
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        13 hours ago

        To be fair, Google searching Roman numerals clocks give you about a 50/50 distribution.

        I wasn’t aware of this either and I suspect we’re not alone. It’s not highly noticeable and if there’s a 50-50 chance won’t even see it…

  • FreedomAdvocate@lemmy.net.au
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    13 hours ago

    Relatively funny but gets worse the more you think about it.

    The 6 stands for 6, not 30.

    When we have AM and PM it would be dumb to have 1-24.

    1 is the end of the 1st hour. 2 the end of the second. This is why it starts at 0.

    • mhague@lemmy.world
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      4 hours ago

      It sounds like a joke but I really had someone stop me on the street to ask for the time and when I said 2:30 they asked “AM or PM?” I guess a 24 hour clock would’ve prevented that.

    • neonred@lemmy.world
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      9 hours ago

      No it’s not, with a 12h format on an analog watch you can use the sun to find true north. It is also easier to read it when the hands have double the amount of degrees to indicate the number.

      Edit – digital watches should use 24h, I fully agree, maybe there was a misunderstanding because it’s analog watches we’re talking about here and these could stay 12h IMHO

      • Hoimo@ani.social
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        12 hours ago

        How do you find north on a 12h face that wouldn’t work with a 24h face? Because the method I know, requires correcting for the 12h circle.

          • Hoimo@ani.social
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            7 hours ago

            Yeah, that’s the method I know.

            Divide the angle that is made in half

            And that’s how you correct for the 12h face.

            • neonred@lemmy.world
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              7 hours ago

              Thought as much but never had any experience with 24h watches, so no comment on this from my side :)

              • Hoimo@ani.social
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                4 hours ago

                With a 24h watch, you line up the hour hand with the sun. Because the sun does a full circle in 24h and the hour hand does the same, lining them up will always make 24 point north (on the northern hemisphere).

                A compass is still the better option, because the magnetic field also points north in the southern hemisphere and doesn’t have to be recalibrated when you move too far east or west.

        • neonred@lemmy.world
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          9 hours ago

          I have never seem a 24h wrist watch (I know they exist) aside from extremely seldom as wall clocks

          • Hoimo@ani.social
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            7 hours ago

            I’ve looked for them, but they’re very hard to find and expensive too. You can’t just slap a 24h face on a 12h mechanism, so it’s all custom and produced in low volumes. (I think it’s technically possible to convert a 12h period into 24h by switching out a single gear, but that might ruin your minute hand too? I’m no clock maker.)

            • bluewing@lemm.ee
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              5 hours ago

              They don’t have to be expensive, though such watches are less popular for everyday use. In fact I’m wearing a Vostok Kommendurski with a 12/24 hour dial. When I was a medic, I needed to record all my times in 24hr format on my run reports. I think I paid $35US delivered from Russia 15 or so years ago.

              And no extra gear is needed to make an analog watch/clock indicate 24 hour time. Time doesn’t change. You simple have one scale that reads from 12AM through 12PM and then at the next hour, (1PM) it simply gets renumbered to 13, 14, 15, 16 and so on until you reach 24 on the inside scale. Easy peasey.

              But it is possible to build a watch/clock that the movement does move in 24 hour time and you would be correct it would a couple of extra gears to accomplish. But, it would also be a real pain to create a legible watch face with all those numbers on a reasonable sized watch. Far simpler and easier to print the two scales on the face and call it good.

              • Hoimo@ani.social
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                5 hours ago

                You paid $35 for the watch, the delivery or both? Because I saw those Vostok watches with proper 24h faces, which is exactly what I’m looking for, but they’re $140. I guess that’s not super expensive for a watch, but I can get a much nicer 12h watch for that money.

                And a double numbered clock face is the simple solution, probably more convenient to read, but also not really a conversation starter :)

                Vostok Komandirskie

        • dependencyinjection@discuss.tchncs.de
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          12 hours ago

          How the heck do you find north based on your watch? I’m pretty good at knowing where north in based on where I am.

          I live in north Manchester so I know Manchester is south. Or I can look at the sun if not midday and figure it out.

          • Alaknár@lemm.ee
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            12 hours ago

            How the heck do you find north based on your watch?

            Like this

            I live in north Manchester so I know Manchester is south

            What if you go on a trip to Thailand and get turned around in the jungle?

            Or I can look at the sun if not midday and figure it out

            That gives you a very approximate direction.

              • Alaknár@lemm.ee
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                2 hours ago

                You don’t need to stare directly into the ball of fire to determine where the Sun is. All you need is the flashes of light through the leaves - and you CAN see that in the jungle.

            • bstix@feddit.dk
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              11 hours ago

              It’s the same method.

              The distance between the sun and 12 is divided by two, because the clock face only shows half the day.

              If we had a clock with 24 hours in the circle and used the same method, it’d be the same as pointing at the sun and saying: South is where the sun will be at noon.

  • WanderingThoughts@europe.pub
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    23 hours ago

    IIRC they counted the bones in their fingers using their thumb and that gives 12. The first sundial was around the equator and there is always light for half a day, so half a day becomes 12 hours.

    To count large numbers often one hand was used to count using 5 fingers and the other to count the bones, so you get 5x12 for 60 minutes.

    • WolfLink@sh.itjust.works
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      22 hours ago

      AIUI there was an aspect in the divisibility of the numbers being convenient.

      12 is divisible by 2, 3, 4, and 6. 60 is divisible by 2, 3, 4, 5, 6, 10, 12, 15, 20, and 30.

      10 is divisible by 2 and 5. 100 is divisible by 2, 4, 5, 10, 20, 25, and 50.

      If you want to minimize dealing with fractions, 12 and 60 are far more convenient than 10 and 100.

      • WhatsTheHoldup@lemmy.ml
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        21 hours ago

        That’s an interesting thought, but I believe it to simply be a coincidence.

        The base 12 counting being based on counting the division of your fingers is historically verified, but if the division aspect was so compelling to them you’d expect it to carry forward into their writing system.

        By the time you get cuneiform math though, they actually go back to base 10.

        https://images.app.goo.gl/9GR6VEiT7GHYF3KaA

        As you can see base 12 is not in the written system, or for written mathematics. It just was convenient for counting on their hands.

        They used mixes of base 10/base 12 and base 60.

        Base 10 would be used go determine the symbols for a specific “digit” in base 60.

        So similar to how our 13 is 1 ten and 3 ones, their 13 was the symbol for 10 then 3 symbols for 1. 13 = 𒌋𒁹𒁹𒁹 But 73 would be written 𒁹 𒌋𒁹𒁹𒁹

        Which would be interpreted as 1 sixty and 13 ones, or 60 + 13

  • WhatsTheHoldup@lemmy.ml
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    22 hours ago

    Don’t listen to OP’s bullshit.

    They work for big clock. They’re trying to convince you 12 hour clock is useless so they can sell you double the clock.

    • Frozengyro@lemmy.world
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      21 hours ago

      Look at this guy, only one clock. I keep two analog clocks in each room, the AM 12-11, and PM 12-11. The way it was meant to be.

  • folekaule@lemmy.world
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    1 day ago

    At least our hours are the same length regardless of latitude now, so let’s be grateful for that.