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Reminds me of the collective confusion in english class when they taught us that 12:15 am is in the night and 12:15 pm is at lunchtime.
Imo anyone using 12:XX am for midnight for the sake of “symmetry” with 12:XX pm or whatever is adding pointless complications on top of the already pointless am/pm system. Midnight has no reason to not be 00:XX am in that system
It ain’t about symmetry or pointless complications. It’s about how many numbers can you get on a watch face and have it be easily legible. Yes, I know there are digital watches these days. But some people don’t like them and some of us need those analog faces. As an old medic, digital watches absolutely suck at timing things like BP or respiration’s. Neither me or my patient had time for that digital watch to zero so I could get a BP in 15 seconds. Ten’s of thousands of EMS people and nurses in general are wearing 12 our analog watches around the world right now.
Now my run reports were all done n 24 hour time because the little boxes on those paper run reports were tiny and often filled out in a hurry. So 24 hour time was more legible and clear to anyone reading the report.
Besides, can you not look out a window to see if the sun is up or not? That will tell you all you need to know to understand how to use 12 hour time.
Its not about understanding it. Its about using it. I cannot tell you the number of times I had set an alarm 12 hours off before switching to 24 hour time. After I switched it never happened again.
Besides 24 is divisible by 12 so you can just double up the numbers on an analog clock. I have an analog watch with 24 hour face that looks similar to this:
Idk, I get your arguments but I’ve seen quite a lot of beautiful watch faces with small 24 hours numbers under the 12 hours one. Of course it works best with the big ones, but that seems to be in fashion these days.
I have no inherent issues with using or understanding 12 hours time, I just think it is actually adding complexity to something that is already pretty much perfect, for reasons that are mostly cultural nowadays (you’ve gotta admit that your point about hospital workers, while very valid, is still kinda isolated. Plus when I was wearing my watch with a 12 hours face daily I just did the x2 multiplication in my head).
Also there’s a reason basically all militaries use 24 hours, and I don’t think it’s because they think highly of their average soldier’s intellect.Besides, can you not look out a window to see if the sun is up or not? That will tell you all you need to know to understand how to use 12 hour time.
That reminds me how after not sleeping for 3 days (I studied for an exam) I fell asleep randomly on my bed (more like passed out) and woke up to a low sun, the analog clock showing like 7:00, and I could not tell whether the sun was rising or setting.
(As a side note: I didn’t have a clue whether my window went out to the west, east, north, etc, and I was way too groggy to even think like that. It was more the color of the light in the room that was ambivalent. Obviously I checked my phone rather quickly and didn’t need to figure out the position of the sun to understand whether it was morning or evening)
Just remember that m is midday, when the sun it high in the sky. Anything with an a is before that moment, everything with a p is after that. It’s not that hard. Now, making heads or tails of thumbs, feet and miles. That’s a head scratcher.
I’m not saying it’s hard, and we got the explanation too. It’s about what feels or seems off. It’s technically correct, I know, but the first reaction of the class was confusion and a lack of intuitive understanding. Mostly it is using 12 instead of 0.
It seems off if you look at it from a purely numerical point of view. If you tackle it from a geometric POV and the face of a clock, it makes sense. That time representation was meant to be cyclical, not lineal. Time is a circle, not a vector.
I see what you mean and where you’re coming from, and I also realize there are historical reasons for 12 hours, there’s a reason it’s called "p"m and "a"m and so on. Still, it does not feel intuitive to jump from 11:59 am to 12:00 pm, go on to 12:15 pm, and end up at 1:00 pm again. It feels like an either or thing. Either you go to 12:00 am after 11:59 am, or you go to 0:00 pm. I understand why it is pm and why it is 12, I am just saying, it feels off to me (and, as mentioned above, the whole class of German students). I absolutely understand that it feels much more natural and less counterintuitive if you have grown up with this system.
For an analog clock the reason for 12 hour time is that twelve divides evenly into 60 and 24 does not. Get rid of the whole 60 min/hour and 60 sec/min that make dividing a clock dial into 60 segments extremely useful and then we can talk about why there are twelve hours on it.
Actually that is not funny to make fun of thing you don’t understand.
A clock is a marvel using a plan to represent both numerically and in volume the time passing in an infinitly précise manner as it is continuous. Human reading precision can be chose at the level of the hour, the minute of the second. The 12-base allow a reading of the twelveths of the time period, the thirds, the halves and the quarters. The use of a circle make it possible to use it as a chronometer at any given start and follow the passing of time as your society see it.
That is just the data representation part!
The clock is also a marvel of ingeneering in the backend with very complex mecanism giving it a excellent precision and the abillity to run on many many different type of power.
the most impressive thing to me is that people managed to standardize and zero in a precise “second” especially back when seconds were kept by mechanical means. I wonder how they went about ensuring it.
A 1m pendulum has a 1 second half-period.
is it not dependent on mass at all? It’s possible given that this is the metric system that this is actually just a convenient retroactive truth about meters. I suppose it wouldn’t necessarily be, but then you’re accounting for gravity as well, which means you’re going to need a pretty effective approximation there. As well as a way to account for any mechanical losses as well.
I’m not sure the metric system even existed when we developed the first mechanical time keeping devices.
So I did some digging and the use of 1-second pendulum as a unit of length predates the metre by about a century. It’s very possible it informed the choice of ratio to use when defining it properly, like we did with the recent definition change.
It’s all on Wikipedia if you want to dive in yourself.
that sounds about right. About what i expected, i’ll have to do some reading sometime i suppose.
The mass cancels out.
I don’t know if it’s purely a coincidence. The meter comes from the Earth’s circumference (1/10 000 000 of the pole-equator distance) and I believe the second is much older, which points to a coincidence.
it makes sense that the mass does cancel out, it is a change of potential and kinetic energy at all, i suppose i’m just conflating more complicated things with it lol.
it’s pretty likely to be a coincidence, but if i had to guess it’s a “lucky coincidence” one that was intentionally chosen because of it’s convenience. Rather than by pure happenstance. There’s not a particularly good reason 1 meter needs to be 1/10000000 the pole equator distance for example. So that would be pretty easy to reverse fudge nicely.
At least that’s an useful approximation, but too inprecise for accurate measurements over an entire day.
It’s only 0.3% off. You probably have more uncertainty on the length of the pendulum.
0.3 % would correspond to 3 mm difference in length of the pendulum.
After an hour, the difference between real and measured time would already be 10.9 s, and over an entire day, it would accumulate to 261.3 s, way too much for useful long term measurements.
Yet, it is an useful approximation for qualitative measurements, e.g. when Galileo Galilei did his fall experiments, he might have used a prendulum instead of his pulse for measuring.I’m not hauling this as the ultimate time keeping method. Friction in the system will mean you need to readjust it anyways. It’s just a neat fact that pi^2 ~= g
Atomic measurments, it’s why atomic clocks are the most accurate.
that’s a recent invention though, the first mechanical time keeping devices are what’s interesting to me.
The atoms are the powerhouse of the clock.
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Should watch an old BBC miniseries, Longitude.
So much fun watching how crazy clocks are engjneered, and Jeremy irons.
Thank you. I add it on the list (^_^)
I was fascinated by some of the crazy things people tried to get working that were discussed on that show. Things like keeping a pair of dogs, wounded by the same knife, as a way to synchronize time. As if they were some kind of quantum entangled particles.
Edit: Found it!
The powder was also applied to solve the longitude problem in the suggestion of an anonymous pamphlet of 1687 entitled Curious Enquiries. The pamphlet theorised that a wounded dog could be put aboard a ship, with the knife used to injure the dog left in the trust of a timekeeper on shore, who would then dip said knife into the powder at a predetermined time and cause the creature to yelp, thus giving the captain of the ship an accurate knowledge of the time.
Oh God… Weren’t this people happy water clock and other sandglass-like engine?
Is this from Timecube?
No it is from good sense and observations of technology inherited of extremly ancient civilisations.
The clock evolved out of the sundial. 12 hours on the clock makes more sense if you think of it that way.
ever think about how 5 is 1/12th of 60? that means putting 5 min and 1h on top of each other is genius imo. because there are 12 times more minutes in an hour then there are hours in a day
there are 12 times more minutes in an hour then there are hours in a day
24 x 12 is 60? You are a weird mathematician.
yeahur right i meant to to say there are 5 yimes more minutes in an hour then there are hours in half a day xD
The twelve comes from the babylonians, which counted the segments of four fingers with their thumb. So each hand could count to 12, which is far more useful than 10 as a base, since it can be divided by {1,2,3,4,6}.
The sound of Babylonian growling intensifies… (Babylonian / Sumerian cultures used the base 12/60 system)
And it remains a sensible system that we rejected because of the ‘superiority’ of the Decimal system.
The Mesopotamian System can reasonably be divided by 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, and 60. All without fractions!
Even the much-vaunted Greeks of antiquity lifted wholesale from the peoples of the fertile crescent- it’s why we still use 360 degrees to measure circles.
“The day starts at night” sounds silly because it seems to be a contradiction. But really, how else could it be?
Either, day starts at day … but then it was already day. Or, day starts at night … unless we come up with additional entities like dusk or dawn.
And since we haven’t introduced them yet, day has to start at night, as a necessity.
Of course the actual silly thing is that it’s still night right after day has started.
The silly thing about this joke in the OP is that day means both “when the sun is up/the opposite of night” and “a period of 24 hours”. English has a lot more words than my native language of Norwegian, but in this case we actually have separate words for the two aforementioned things.
What are the words?
Døgn vs dag
starts at midnight?
Gilgamesh joins the chat. The Sumerians and the duodecimal system for time keeping.
Base 60 is actually a lot more practical than base 10.
How do you count on your hands in base 60?
It sucks, it requires way too many digits.
Then why computers use the binary system and not base 60?
The U.S. 12h clock is stupid: 12PM + 1h = 1PM
If you don’t use a 24h clock at least do it like the Japanese, who also use the 12h clock and have: 0:00 PM + 1h = 1:00 PM
that just moves the weird math, because 11:00 + 1h = 00:00… The fact that clocks are a circle means there is some weird math like this happening somewhere no matter the system.
Not really 11:00 AM +1h becomes 00:00 PM, and vice versa. PM and AM are different prefixes/systems/units. Much simpler to understand IMO. 12:00 AM and 12:00 PM would no longer exist, you just convert them from PM to AM or back when you reach them and set the numbers to 00 again.
This is basically the same system as the regular 12:00 clock except noon and midnight are 00:00 instead of 12:00.
Seems functionality the same to me.
24 hour is the only way. If only I could convince people to stay saying “15 O’Clock”. That would be neato. People know what it is, just not used to it
turns out Americans really love the modulo operation, no wonder programmers are paid so well there
Aand that’s Numberwang!
This joke has lived in my head quietly for at least a decade.
That’s wangernumb
Well, it’s still a far plan than the time the French tried to force time into base 10…
Which might have been the first documented demonstration of the saying “The French follow no one. And no one follows the French.”
They also tried to implement a metric calendar, ya know I think I know why they started using the guillotine on the revolutionary leaders.
It might have been an extra reason.
It’s a lot of different things it’s design is based on the sundial, we already had base 12 time
Wikipedia page for base 12, the origin is a fun read and while I can’t say it’s all accurate, the parts I know are
They don’t know how to switch bases
🤣😂🤣
😶
Wait until you use dms to navigate a map
That’s fun
