Today I Learned

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Today I learned that cleaning a white hat can be done with bleach cleaner, but it’s important to rinse it before wearing it again. I also discovered that "oyster veneering," a woodworking technique from the late 1600s, is experiencing a minor revival despite its labor-intensive nature. Additionally, I learned that the factorial of 23 (23!) equals 25,852,016,738,884,976,640,000, which interestingly has 23 digits, a unique coincidence among factorials. I found out that medical specialists often spend less than 10 minutes with patients, and that watching TV can contribute to weight gain. Other insights included the fact that a kiss can transfer around 80 million microbes, and that bureaucracy can sometimes hinder employment opportunities. The discussion also touched on various trivia, such as the emotional sensitivity of barn owls and the complexities of gravitational lensing around black holes.
  • #6,241
jack action said:
Draaaaaat!
Talk about a watched kettle never boils...

They watched it for ten years!
 
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  • #6,242
jack action said:
Draaaaaat!
A phenomenon well known from MicroSoft updates and installations. The moment you leave the room it will stop the process and ask you silly questions.
 
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  • #6,243
fresh_42 said:
A phenomenon well known from MicroSoft updates and installations. The moment you leave the room it will stop the process and ask you silly questions.
Unlike Netflix, which asks you if you're still watching - while you're still watching.
 
  • #6,244
jack action said:
TIL about the Oxford Electric Bell that has been ringing every half second since 1840. Nobody knows for sure the composition of the dry piles for the setup.

Excellent! Thanks, this is new to me and now I want to make one.*

Why 1/2 second period? Is it dominated by the RC time constant of charging the bells? The period of the pendulum?

The dry cells, probably Ag, Zn, and paper must have an electrolyte, right? What is the electrolyte and why are they called "dry"?

* Yea, nope, don't bet on that. I'm pretty lazy these days plus I'm in the middle of remodeling the only real bathroom in our tiny house. But I can still dream, can't I?
 
  • #6,245
The longest continuous vocal note is 2 min 1.07 sec, and was achieved by Richard Fink IV (USA) in Las Vegas, Nevada, USA, on 17 November 2019.

(scroll down a bit for a video --- towards the very end, it begins to feel like it could end up being Richard's swan song).
 
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  • #6,247
TIL
https://www.gowinglife.com/of-webs-and-weed-why-nasa-drugged-spiders-and-what-we-learnt/ said:
In 1995, NASA scientists published a study in which marijuana, benzedrine, caffeine or chloral hydrate (a sedative and hypnotic drug) were given to spiders, and the effects on their webs observed. [...] However, unlike previous studies, NASA was able to apply modern computing and statistical methods. They digitised the web structures, and found that the structure of the web correlated with the toxicity of the substance being tested. Specifically, the more toxic the substance, the fewer sides of each web ‘cell’ the spiders completed.

[...]

However, the spiders don’t lie – caffeine is at the very least quite a bit more toxic than marijuana

spider-webs.jpg
 
  • #6,248
jack action said:
Pointless without a discussion of the dosage. You can kill yourself by drinking too much water, after all. Plus web construction by spiders is a strange metric, why should we care? I don't know what all of this means.
 
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  • #6,249
DaveE said:
Pointless without a discussion of the dosage. You can kill yourself by drinking too much water, after all. Plus web construction by spiders is a strange metric, why should we care? I don't know what all of this means.
Indeed.

We know that chocolate is harmful to dogs, but that doesn't prove it's harmful to humans.
 
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  • #6,250
The Oklahoma City Zoo once killed an elephant by injecting it with 297 milligrams of LSD.
 
  • #6,251
DaveE said:
Pointless without a discussion of the dosage. You can kill yourself by drinking too much water, after all. Plus web construction by spiders is a strange metric, why should we care? I don't know what all of this means.
I like that they used "modern computing and statistical methods" to do the analysis in 1995. I wonder if today's AI would find more interesting patterns and links.
 
  • #6,252
Ivan Seeking said:
... In S California it would be solid city from LA to San Diego, but the San Onofre nuclear power plant required a large unpopulated radius. That is shut down now but I haven't been down there for a long time. I don't know if that area is filling in yet or not. They still have 3.5 million pounds of nuclear waste.

The developers would have to fight the US Marines. That "area" is their Camp Pendleton, been there since WWII. It isn't unpopulated due to the nuclear plant, rather because the Marines train there. I remember watching the tanks climbing up and down the foothills opposite the plant site. The wiki is interesting
https://en.wikipedia.org/wiki/Marine_Corps_Base_Camp_Pendleton

I don't recall the details but I think So Cal Edison leases the property from the Navy.

Sorry for the necro post, I was behind in my "TIL" reading.
 
  • #6,253
TIL Wikipedia...The gimbal was first described by the Greek inventor Philo of Byzantium (280–220 BC).[3][4][5][6] Philo described an eight-sided ink pot with an opening on each side, which can be turned so that while any face is on top, a pen can be dipped and inked — yet the ink never runs out through the holes of the other sides. This was done by the suspension of the inkwell at the center, which was mounted on a series of concentric metal rings so that it remained stationary no matter which way the pot is turned.
 
  • #6,254
TIL how the ancients figured out the distance to/size of the Moon and Sun. Aristarchus of Samos in 250 BC showed that the Sun was larger than Earth and so proposed that the Earth orbited the Sun. Though the idea didn't catch on, Aristarchus' priority was credited by Copernicus.



Albert Einstein declared that Kepler's method for determining the shape of the orbit of Mars was "an idea of pure genius." Part two of this presentation is not to be found but this is available.



I have long wondered why measuring the time of the transit of Venus across the Sun was an important motivation for the voyage of Captain Cook. Now I know.
 
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  • #6,255
TIL that When You Wish Upon a Star is from the movie Pinocchio.
 
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  • #6,256
Today I learned that film director John Ford was "quite friendly" with former gunman Wyatt Earp.

 
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  • #6,257
Spoiler for anyone playing NY times Strands game.


TIL: Platypi are not only egg-laying mammals. Male platypi are also among the rare mammals that are venomous, delivering the venom through spurs on the hind legs. It is apparently quite painful.
 
  • #6,258
Orodruin said:
Spoiler for anyone playing NY times Strands game.


TIL: Platypi are not only egg-laying mammals. Male platypi are also among the rare mammals that are venomous, delivering the venom through spurs on the hind legs. It is apparently quite painful.
I actually knew this already due to consuming reliable scientific sources on the subject.
 
  • #6,259
  • #6,260
Borg said:
TIL about the O.W.C.A. (Organization Without a Cool Acronym). :oldlaugh:
Pronounced as Oucha.
 
  • #6,261
Recently J005311 was discovered. It is believed to have formed out of the merger of two white dwarfs. Usually this results in an explosion but this time did not. They merged and fusion started up again. Once that runs out of fuel it is predicted that J005311 will collapse into a neutron star.

A Japanese film maker produced a low budget film under that title J005311 about two despairing losers who get bound up together. Presumably it has a happy ending.
 
  • #6,262
Borg said:
TIL about the O.W.C.A. (Organization Without a Cool Acronym). :oldlaugh:
Ah. Not a mere TLA - an ETLA* in the wild.

* extended TLA **

** three letter acronym
 
  • #6,263
IBM WRT ENR OSY WTH TLA. PWRDWNSYS.
 
  • #6,264
TIL that the Huntington Beach city council meets in front of a surfboard mounted behind them on the wall.
 
  • #6,265
jack action said:
TIL that ##1089## is a number that is very practical in magic.

For example, take any 3-digit number in descending order and subtract its "reverse" number. Ex.: ##632-236=396##. Then add the "reverse" number of this answer and you will always get ##1089 (= 396+693)##.
Yes..., but.
It works in any other base, too.
Take this octal 632, so
632 - 236 = 374 (octal)
374 + 473 = 1067 (octal)

So basically for 3 digit numbers in any base. The answer is ABCD
Where:
A = 1
B = 0
C = base - 2
D = base - 1

I'm interested in Sheldon's (The Big Bang Theory) favorite number: 73 (decimal)
73 is the 21st prime,
while the reverse of 73: 37 is the 12nd prime.
And 7 * 3 = 21,
I'd like to search this pattern in other bases, but have to write a computer program, first.
 
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  • #6,266
I'd like to try binary.
101 - 010 = 011
011 + 110 = 1001
A = 1
B = 0
C = 2 - 2 = 0
D = 2 - 1 = 1, checked.

Hexadecimal...
D3A - A3D = (calculating...) 2FD
2FD + DF2 = (calculating...) 10EF,
A = 1
B = 0
C = 16 - 2 = E
D = 16 - 1 = F, phew...
 
  • #6,267
Let's try any number, condition: C>A
CBA - ABC = (C * 100 + B * 10 + A) - (A * 100 + B*10+C)
Result: (backward)
(Base + A-C), have carry
(B-B-1) * 10 = (Base-1) * 10, have carry
(C-A-1) * 100,
that would be.

(C-A-1)*100 + (Base-1) *10 +(Base + A-C) plus reverse (Base + A - C)*100 + (Base - 1) * 10 + (C - A - 1)
Result: (backward)
(Base - 1) +
(Base - 2) * 10, have carry
(Base + C - C + A - A + 1-1)*100 = 10
Yep, it's
1
0
Base - 2
Base - 1

I think this is not a conjecture, it's a fact. Anybody think so?
And one more thing, any civilization here on earth and in this space time always use base 10!
 
  • #6,268
KingGambit said:
And one more thing, any civilization here on earth and in this space time always use base 10!
Not true.

Maybe bases have been used throughout history and many still are. I use base 2 all the time.
Land coordinate systems and astro coordinate systems use base 60.

Some light reading: https://en.wikipedia.org/wiki/List_of_numeral_systems
 
  • #6,269
DaveC426913 said:
Not true.

Maybe bases have been used throughout history and many still are. I use base 2 all the time.
Land coordinate systems and astro coordinate systems use base 60.

Some light reading: https://en.wikipedia.org/wiki/List_of_numeral_systems
Yes it is!
Just ask a civilization that say, use hexadecimal.
What base that you use?
They will answer:
10! (and in our number that means something that counts xxxx xxxx xxxx xxxx -> 16 in our decimal)

Ask an octal civilization: what number this is: xxxx xxxx
And they will answer: Oh, that's 10 (octal)

Sorry, bad math jokes :smile:
 
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  • #6,270
KingGambit said:
Yes it is!
Just ask a civilization that say, use hexadecimal.
What base that you use?
They will answer:
10! (and in our number that means something that counts xxxx xxxx xxxx xxxx -> 16 in our decimal)

Ask an octal civilization: what number this is: xxxx xxxx
And they will answer: Oh, that's 10 (octal)

Sorry, bad math jokes :smile:
A joke appeared in some places, :
There are 10 types of people. Those who understand binary and those who do not.

edited.
 
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