Today I Learned

  • Thread starter Thread starter Greg Bernhardt
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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.
  • #841
nucleargirl said:
Today I learned that the red fox habitat is expanding into the arctic fox habitat and the red fox will eat the smaller arctic fox... :S
Yes, I think I heard something about it...in Fox news.
 
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  • #842
Today I learned how to remove a chuck from a drill:



The information that the holding screw inside the chuck is left-handed was invaluable.
 
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  • #843
Today I learned that four rare Earth metals Yttrium (Y), Terbium (Tb), Erbium (Er) and Ytterbium (Yb) are all named after Ytterby a town in Sweden.
 
  • #844
I learned that snakes, worms and spiders are tailless.
 
  • #845
Today I learned why we get goosebumps. I always took it literally and assumed it was because a goose's hair will fluff up when it's cold, but It's actually because we evolved from animals with fur and when you have fur getting cold is somewhat alleviated by causing your hair to fluff up. We make the same motion (goosebumps) we just don't have any fur to stand up. Same reason as geese really but not the right derivation.

Also fright seems to cause hair to stand up on some animals necks so we sometimes get them on our necks when we see something frightening.
 
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  • #846
phinds said:
Today I learned why we get goosebumps. I always took it literally and assumed it was because a goose's hair will fluff up when it's cold, but It's actually because we evolved from animals with fur and when you have fur getting cold is somewhat alienated by causing your hair to fluff up. We make the same motion (goosebumps) we just don't have any fur to stand up. Same reason as geese really but not the right derivation.

Also fright seems to cause hair to stand up on some animals necks so we sometimes get them on our necks when we see something frightening.
Yes, the technical term for "goosebumps" is piloerection:

Medical Definition of PILOERECTION. : involuntary erection or bristling of hairs due to a sympathetic reflex usually triggered by cold, shock, or fright or due to a sympathomimetic agent.
 
  • #847
zoobyshoe said:
Yes, the technical term for "goosebumps" is piloerection:
Cool. Thanks.
 
  • #848
TIL it's hard to tune a lecture to the students needs when you have both students with dyslexia and dyscalculia.
The first benefit often from a schematic way of summarizing the contents using fewer words/full sentences.
While the latter not only have trouble with arithmetic but also with visual insights.
This means they can have trouble with a schematic way of representing the contents.

Quite the conundrum when trying to (fine-)tune a lesson.
 
  • #849
zoobyshoe said:
The information that the holding screw inside the chuck is left-handed was invaluable.
i look for burnt out drills in junkpiles and pillage those left handed screws . They must be made from Unobtanium - can't get them anyplace else !
 
  • #850
jim hardy said:
i look for burnt out drills in junkpiles and pillage those left handed screws . They must be made from Unobtanium - can't get them anyplace else !
You made me curious. The one I took out of a 3/8 black and decker drill seems to be a 3/16-32 screw, which is a size I have never heard of before. I get a diameter of .186 and 32 TPI.

I suppose you could call a drill manufacturer and tell them you change your chucks often and are always losing the screws. Maybe they'd send you a box?
 
  • #851
zoobyshoe said:
The one I took out of a 3/8 black and decker drill seems to be a 3/16-32 screw, which is a size I have never heard of before. I get a diameter of .186 and 32 TPI.

That seems within tolerance for a 10-32. It an be as small as 0.184 and still meet class 3.
http://www.engineersedge.com/screw_threads_chart.htm
upload_2015-12-6_4-5-7.png

0.1861 would be smack in the middle of grade 2.

from http://www.engineersedge.com/thread_strength/thread_classes.htm
upload_2015-12-6_4-7-45.png


old jim
 
  • #852
jim hardy said:
That seems within tolerance for a 10-32.
Of course. I don't know why I dismissed that. A left handed 10-32 screw might be easier to find than a left handed 3/16-32, heh heh.
 
  • #853
zoobyshoe said:
Of course. I don't know why I dismissed that. A left handed 10-32 screw might be easier to find than a left handed 3/16-32, heh heh.

With my luck it'd be Whitworth threads - same pitch but 55 degrees...
 
  • #854
TIL that endarterectomies are not fun.
 
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  • #855
Bystander said:
TIL that endarterectomies are not fun.
That certainly doesn't sound like fun. Hope you're doing better.
 
  • #856
Today I learned that "stressed" spelled backwards is "desserts." Our college's dining hall had a special dessert bar set up today for final exam week.
 
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  • #857
Today i learned that costalota means taking two women shopping.
 
  • #858
wolram said:
Today i learned that costalota means taking two women shopping.
Is that something like Ménage à cash?
 
  • #859
Last week, I noticed that my fish made a baby.
Being egg layers, I assumed there were more babies. I've counted about a dozen so far.
But in my searches, I noticed some tiny little "Hydra" looking creatures.

tanichthys.albonubes.hydraish.creature.mm.jpg

No big deal.

But I googled "Hydra", and discovered that, they are immortal. [ref wiki]

I didn't know such creatures existed.
 
  • #860
Today i learned that a trivial topological space is pseudo-metrizable.
 
  • #861
Ewww, the white fish...
 
  • #862
TIRT I'm mainly on my silent mode these days! :sleep:
 
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  • #863
Today I learned that the Earth's axis precesses because the Earth is oblate.
 
  • #865
Today I learned that a parsec is 3.262 light years long, and that the total number of possible 6 number combinations from the range of 1 to 39 inclusive are 3.262 million.
 
  • #866
Today I learned that James Clerk Maxwell was the first to project a color image using the red-green-blue system.

I also learned that a few people can see a fourth color, so RGB is inadequate for them. One of these said the world of man was full of clashing colors, and that supermarkets were the worst.
 
  • #867
TILT my problems with the boss might be side effects of the medication that I'm taking!
But that doesn't change the fact that she's really annoying and it's hard for everyone to stand her. :oldwink:
 
  • #868
TIL how to re-attach the back of a violin using 'hide glue' .
 
  • #869
TIL how to make chicken jalfrezi in a slow cooker. A hint if you try it: don't be in the house smelling the lovely spicy cooking smell for six hours. I felt like one of Pavlov's dogs...
 
  • #870
TIL about drought tolerant plants (good GMO :woot:) which help dry farmers to cope with water shortages.
 

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