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.
  • #5,201
DrGreg said:
Today I learned that the PracticalCryptography website does not support HTTPS.
Curious, http://www.russinovich.com is the same. Author of several cyber security novels.

"Someone might be able to see the information you send or get through this site."

scary ? nah
 
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Ibix said:
TIL that Jif is not lemon juice in America, but peanut butter. I already knew it was a cleaning product in some countries.
If one visits Walmart, a cleaning fluid named _Bona_ is clearly present at eye level on the shelf, however as far as I know, there is no _Naff_.
 
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TIL The drones are tuned in a bag pipe, I thought the piper blew up the bag and off he went.

Far from it.

The drones are Bb and octave apart (on the ones I have checked) and the tune is played on the chanter with his fingers

In the wiki link below there is a recording of the “Skye boat song.”

The top note at the end each phrase sounds flat which I thought odd if they want to showcase an instrument on wiki.

https://en.wikipedia.org/wiki/Bagpipes

I may contact bag pipe news see what their view is
https://bagpipe.news/

The inspiration for this informative thread was this thread https://www.physicsforums.com/threads/excellence-on-obscure-instruments.1053063/

#31 – Bag pipes at a wedding from @DennisN
 
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pinball1970 said:
TIL The drones are tuned in a bag pipe, I thought the piper blew up the bag and off he went.

Far from it.

The drones are Bb and octave apart (on the ones I have checked) and the tune is played on the chanter with his fingers

In the wiki link below there is a recording of the “Skye boat song.”

The top note at the end each phrase sounds flat which I thought odd if they want to showcase an instrument on wiki.

https://en.wikipedia.org/wiki/Bagpipes

I may contact bag pipe news see what their view is
https://bagpipe.news/

The inspiration for this informative thread was this thread https://www.physicsforums.com/threads/excellence-on-obscure-instruments.1053063/

#31 – Bag pipes at a wedding from @DennisN
I bet that flatness is deliberate.

I live in Bali. The gamelan notes are close to a pentatonic scale but deliberately "sour" to give it a certain character.

Country blues was tuned by ear and usually didn't match orthodox pitch correctness. It gives the sound personality.

In Thailand karaoke is popular. Often I'd be far enough away I could hear only the singer, not the background. It sounded grossly out of tune to me so I'd be sure to pack ear plugs. If you can hear the chords though it usually made sense. Asian singing often uses "out of tune" notes that in the West only little children sing.
 
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TIL... about the Lesbian Rule and its relationship to Dark Matter. (Not what you're thinking!)

Aristotle (via Wikipedia) said:
For what is itself indefinite can only be measured by an indefinite standard, like the leaden rule used by Lesbian builders; just as that rule is not rigid but can be bent to the shape of the stone, so a special ordinance is made to fit the circumstances of the case.
Yep, definitely like Dark Matter.

The puzzling name similarity between the Lesbian Rule (pliable lead) and female-gay seems to be coincidence -- associated with writings of the poet Sappho of Lesbos.
 
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TIL that papyrus is now nearly extinct in Egypt:

 
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Swamp Thing said:
TIL that papyrus is now nearly extinct in Egypt:


I got some growing at my house.
Its an interesting plant (with a lot of history).
 
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Today I learned that The Good, the Bad and the Ugly is called Il Buono, Il Brutto, Il Cattivo in Italian, which means The Good, the Ugly, the Bad. And Spanish has a "two countries divided by a common language" thing going on with it being released in Spain as El bueno, el feo, y el malo (same as in Italian) and in South America as El bueno, el malo, y el feo, (same as in English).

Spanish Wikipedia: https://es.wikipedia.org/wiki/Il_buono,_il_brutto,_il_cattivo. Note the bold text at the top of the first paragraph.

Edit: also, today I learned that if you use the paste key on this phone instead of the popup context menu, it has a nasty habit of replacing a word with what you paste instead of inserting it.
 
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This looks fun:

 
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BillTre said:
This looks fun:


It is fun. 😁 I know I took a photo or two, but I can't find them right now.
 
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BillTre said:
This looks fun:


There was one of those in a shopping mall in Tokyo called Divers City. I went for the zombie apocalypse virtual reality ride instead.
 
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TIL that the Denmark Strait is between Greenland and Iceland. o:)
 
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[Mentor Note: The latest 2 replies in this thread have been placed in Moderation (hidden) pending Mentor review]
 
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Today I learned that in Detroit the 1967 riots remain to this day a popular topic of conversation. I guess for people who lived through it it was by far the most exciting thing that ever happened to them.
 
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Hornbein said:
Today I learned that in Detroit the 1967 riots remain to this day a popular topic of conversation. I guess for people who lived through it it was by far the most exciting thing that ever happened to them.
My granddad had stories about this, but he's dead now.
My dad knew these stories and could related them well, but he's dead too.
I don't care much about it myself. I would have been 14 and living in the DC area at the time.
 
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BillTre said:
My granddad had stories about this, but he's dead now.
My dad knew these stories and could related them well, but he's dead too.
I don't care much about it myself. I would have been 14 and living in the DC area at the time.
Oh sorry!
 
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DeBangis21 said:
Oh sorry!
Not a big deal. Time has passed.
 
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When I was fourteen I was in a rank beginner blues band with Peter Saulson, who played the harmonica. Today I learned he is one of the bigshots administering the LIGO gravitational wave observatory.
 
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Today I learned that Hideki Tojo had Remember Pearl Harbor engraved on his dentures in Morse code.

After the surrender American dentists removed all but seven of his bad teeth. One engraved the message on the subsequent dentures.

Mallory recommended complete upper and lower dentures, but Tojo refused because he thought it would be a waste of effort to make both dentures for someone about to be executed. Instead, he asked for only an upper set of dentures so he could speak well at his trial.

The word got out. Their commanding officer said he appreciated the joke but foresaw trouble. The dentists retrieved the dentures, ground off the message, then under investigation successfully denied all hankypanky.

https://www.wearethemighty.com/mighty-history/tojo-denture-prank/
 
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TIL that sea levels would have been tens of meters higher if water had been perfectly incompressible.
 
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I learned that the more the arc length, the more the p.d b/w the electrode and the weld pool during stick welding.

Question: why is the transformer not shocking?
 
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DeBangis21 said:
p.d b/w
What?

DeBangis21 said:
why is the transformer not shocking?
What? I suppose it is shocking the arc it created.
What do you mean by "shocking"?
 
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DaveE said:
What?
p.d. b/w = Potential Difference BetWeen
 
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phinds said:
p.d. b/w = Potential Difference BetWeen
Yes
 
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DaveE said:
What? I suppose it is shocking the arc it created.
What do you mean by "shocking"?
Electrocution! When one touches the transformer or connect the earth/welding lead (cable) to the machine with bare hands, there is little or no jolt most atimes.
 
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DeBangis21 said:
Electrocution! When one touches the transformer or connect the earth/welding lead (cable) to the machine with bare hands, there is little or no jolt most atimes.
Please do not touch energized conductors with your bare hands. We strongly discourage our members from competing for the annual Darwin awards, and punish them severely after they win one. :wink:
 
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Haha!
 
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DeBangis21 said:
Electrocution! When one touches the transformer or connect the earth/welding lead (cable) to the machine with bare hands, there is little or no jolt most atimes.
And what is the voltage?
 
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The greatest hazard, in terms of accessible voltage, is when there is no arc. You should assume that the arc may extinguish at any time. For example, what if you suddenly have to sneeze, there's an earthquake, whatever...

So, you should assume that it is always dangerous. ALWAYS. If you aren't scared of the voltage, you are at risk. If you are assuming "I just wouldn't do that", you are probably wrong.
 
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berkeman said:
Please do not touch energized conductors with your bare hands. We strongly discourage our members from competing for the annual Darwin awards, and punish them severely after they win one. :wink:
Do you hang them in a gibbet?

1688259136807.png
 
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Question: why is the welding transformer not shocking?

A quick search shows open-circuit AC voltages around 40V to 75V, often half of those values with an arc established.

WIth dry, calloused hands and a light touch, I would not expect much current flow at 40V -- the other extreme and I would expect at least the inability to let go!

(Russian Roulette anyone?)

[edit] Those welding gloves also keep the intense UV light off your hands, you can lose skin without them. [/edit]
 
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  • #5,239
DeBangis21 said:
Question: why is the transformer not shocking?
As far as I know none of the output terminals are grounded: it's kind of an isolation transformer setup, with extras (rectifiers and most likely other electronics these days). This will protect you somewhat under normal circumstances unless you touch (connected to) both terminals. What you most definitely should not do.

The usually recommended gear for welding (rubber soled boots and thick gloves) also has the function of isolation.

Just to keep the topic in the right direction (and also about those gloves):

TIL that what is the real point behind those thick and inconveniently oversized (!) leather gloves old style blacksmiths preferred to have.
... it's that convenient one handed swing to get rid of an overheated glove :doh:
Try that with a tight fitting modern glove... Not workin' o0)
 
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I don't know if it will save farming but the technology looks very cool. I wonder about the energy cost per acre.

 
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Today I learn (after watching all of Lucifer series episodes),
All angels' name end in el
Mikael,
Gabriel,
Raphael,
Remiel,
Jophiel,
etc...
 
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It's the word for God in Hebrew, and their names are all phrases that refer to God somehow.

Edit: or at least, the christian canonical angels' names are so. Whether a TV series stuck to that or just decided that anything ending in -el sounded angel-y is, of course, another question.
 
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  • #5,243
Ivan Seeking said:
I don't know if it will save farming but the technology looks very cool. I wonder about the energy cost per acre.


You have to give it to marketing when it's time to come up with shocking images: "Save farming".

Like that industry could die. "Sorry guys, we can build cars, smartphones, and A/C units, but eating is now a thing of the past. We can't provide anymore."

Farming is the last activity people will stop doing.
 
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jack action said:
You have to give it to marketing when it's time to come up with shocking images: "Save farming".

Like that industry could die. "Sorry guys, we can build cars, smartphones, and A/C units, but eating is now a thing of the past. We can't provide anymore."

Farming is the last activity people will stop doing.
Yes, the title was unfortunate which is why I mentioned it in the first place. They may mean the economic viability of domestic farming in the US.
https://www.migrationpolicy.org/new...gly-have-compete-shrinking-agricultural-labor

But if it works as claimed it could be revolutionary.
 
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Ibix said:
It's the word for God in Hebrew, and their names are all phrases that refer to God somehow.

Edit: or at least, the christian canonical angels' names are so. Whether a TV series stuck to that or just decided that anything ending in -el sounded angel-y is, of course, another question.
Yes, Elohim - Gods

Isra-el - wrestle/struggle with god
 
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TIL, just a moment ago, from sir Zz 2010 thread, that Accelerator Physics is an inter-disciplinary field between Physics and EEE/ME.

That catapult my interest, afterall ME was my first choice, then PHY.
 
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TIL, while doing my lessons on Duolingo, what appears to be two Finnish idioms:
Svengaa kuin hirrvi - "swings like a moose"
Used as in: " This music really swings like a moose".
The other is "Täysi susi" - "full wolf"
which means "a complete failure"
I can see where täysi(full) can also mean "complete", and at first I thought maybe susi just could have more than one meaning, such as kuusi meaning both a spruce tree and 6 (or in some odd circumstance, "your moon".) But so far, no Finnish to English translator returns anything but "wolf".
 
  • #5,248
Recently I've been learning about molten chloride fast nuclear reactors.

Unfortunately, like most of the cool stuff I do, I can't talk about it. :oldeyes:
 
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  • #5,249
Ahh... but now the "Other Side" is 'Coming to Take You Away, Away'!!
 
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