Today I Learned

[Hornbein]

Writer HP Lovecraft wanted to become an astrophysicist, but he wasn't good enough at math.

 

[Hornbein]

Today I learned that Helen Keller was a communist activist. Who would have thought?

"In Our Own Words" by Senator Robert Torricelli includes a Keller speech exhorting the audience to "march towards the red dawn!"

 

[OmCheeto]

Knocking someone out with a handkerchief soaked in chloroform, is mostly Hollywood:

...
Use of chloroform as an incapacitating agent has become widely recognized, bordering on clichéd, due to the popularity of crime fiction authors having criminals use chloroform-soaked rags to render victims unconscious. However, it is nearly impossible to incapacitate someone using chloroform. It takes at least five minutes of inhaling an item soaked in chloroform to render a person unconscious.
...

Background:
I keep a gallon of dilute solution of water and bleach(sodium hypochlorite) in the bathroom to clean things up.
I also recently mixed myself a batch of homemade Febrezey type solution, (water, isopropyl alcohol, & cologne) for quick spritzing. (I saw the price on a 27 oz bottle was over $5, and said to hell with that.)

Anyways, I was worried about mixing the two active chemicals, and this is where I discovered that it creates chloroform, amongst other nasty sounding things: hydrochloric acid, ... chloroacetone or dichloroacetone [ref]

 

[Astronuc]

I've been reading Ladies of Liberty by Cokie Roberts, and I'm reading about Louisa Adams, wife of John Quincy Adams. JQ Adams was an accomplished diplomat (and 6th president of the US), so I was curious about his accomplishments and his political philosophy, which led me to:

https://en.wikipedia.org/wiki/First_Party_System
https://en.wikipedia.org/wiki/Second_Party_System

https://en.wikipedia.org/wiki/American_System_(economic_plan)
https://en.wikipedia.org/wiki/Internal_improvements

Abraham Lincoln thought Internal Improvements was a function of government.

Summaries of their biographies at the White House.
https://www.whitehouse.gov/1600/first-ladies/louisaadams
https://www.whitehouse.gov/1600/presidents/johnquincyadams

 

[OmCheeto]

TIL, the shattering truth, as to why you put champagne glassware on the top shelf of the dishwasher.
I always knew it was the rule, but never bothered to think about, why.

 

[DiracPool]

"Happiness is found along the way, not at the end of the road"

 

[Lisa!]

TIRT I'm addicted to watching a television drama that's about an addict!

 

[skad]

That Genghis Khan's real name was Timuchin.

 

[jackwhirl]

That the at symbol (@) let's you name drop peoples in the forums.
@jackwhirl was here.

 

[zoobyshoe]

That Genghis Khan's real name was Timuchin.

Yes, in Mongolia he's fondly remembered as Timmy Kahn.

 

[Hornbein]

Today I learned rhubarb originally came from China. The "barb" is related to "barbarian."

 

[Hornbein]

Today I learned why the Mercator projection is popular. It told a sailor what compass bearing to use. Sailing with a constant compass bearing is not the shortest route, but is generally close enough.

 

[Hatesmondays]

I learned that playing a soccer game without your glasses on is a bad idea.

 

[Hornbein]

Today I learned that bees like caffeine. About half of the varieties of nectar contain it.

 

[Hornbein]

Today I learned that in the 1930's physicist Ettore Majorana withdrew all his money from the bank, took a short trip on a ship, and disappeared. His fate was learned in 2008 after a TV show about him. A viewer had a photo of Majorana taken circa 1959 in Venezuela.

 

[Borg]

I have been teaching myself the D3 javascript language. TIL about Voronoi diagrams.

 

[TheDemx27]

I have been teaching myself the D3 javascript language. TIL about Voronoi diagrams.

Pic reminds me of this cool page I found on voting system simulations: http://zesty.ca/voting/

 

[zoobyshoe]

Today I learned (by direct measurement) that a new U.S. penny is just about .750 inches in diameter. Like .7495 close. That is potentially handy information that somehow hitherto escaped me.

However, none of the other U.S. coins has a diameter that is of any obvious use.

 

[lisab]

Today I learned (by direct measurement) that a new U.S. penny is just about .750 inches in diameter. Like .7495 close. That is potentially handy information that somehow hitherto escaped me.

However, none of the other U.S. coins has a diameter that is of any obvious use.

Heat it up a bit, you might get to 0.750.

 

[zoobyshoe]

Heat it up a bit, you might get to 0.750.

Good idea. If I need to use them to measure something I'll put them in my armpits for a while first.

 

[Dewgale]

Today I learned that driving Minneapolis freeways in twilight is a terrible experience when you're a wayward Winnipeger.

 

[OmCheeto]

Good idea. If I need to use them to measure something I'll put them in my armpits for a while first.

The US Mint says they are supposed to be 0.75" in diameter. [ref]
Though, they do not give a reference temperature.
So I can't say whether or not that your micrometer is off.

According to the Engineering Toolbox, the coefficient of expansion of pennies should be around 19 microinch/(in °F) [ref]
Being 97.5% zinc, I'm assuming the copper cladding adds little to the equation

According to my calculations, and assuming you are not SATAN, the US Mint's unspecified temperature is 134°F.

In any event, TIL that eating modern zinc based pennies is toxic to both dogs and children.

 

[Astronuc]

Does the SEC inflate its numbers?
https://finance.yahoo.com/news/does-the-sec-inflate-its-numbers-165803420.html

Hmmmm - juggling the numbers?

 

[zoobyshoe]

The US Mint says they are supposed to be 0.75" in diameter. [ref]

I am sure that's what the print calls for, .750, but I'm sure there's a tolerance on that print, as well. They could stamp them out at .7495 for years and they'd all pass inspection. That's actually remarkably good for a part that isn't required to perform in any precision machine. The tolerance on, say, 3/4 washers is probably plus or minus .005.

 

[mfb]

I am sure that's what the print calls for, .750, but I'm sure there's a tolerance on that print, as well. They could stamp them out at .7495 for years and they'd all pass inspection. That's actually remarkably good for a part that isn't required to perform in any precision machine. The tolerance on, say, 3/4 washers is probably plus or minus .005.

Well, they should not be too different, otherwise vending machines won"t accept them (or need a larger tolerance, which makes them more vulnerable to foreign coins).

 

[zoobyshoe]

Well, they should not be too different, otherwise vending machines won"t accept them (or need a larger tolerance, which makes them more vulnerable to foreign coins).

The difference between .750 and .7495 is .0005, five ten thousandths of an inch, which is about 1/8 the thickness of a piece of printer paper. It's pretty small. I am sure more than that is worn off the diameter of any coin that's been in circulation a few years.

Machines that make change probably have several criteria the coin has to meet. The tolerance on the diameter could be more than you would expect, since it would have to pass other tests, as well.

 

[mfb]

The difference between .750 and .7495 is .0005, five ten thousandths of an inch, which is about 1/8 the thickness of a piece of printer paper.

Can we express it as fraction of the average distance to moon? ;)
~12 micrometers difference. Hmm... I could test that with a few coins. Probably 1 (€-)cent as they don't have grooves and I have a few of them. Iron (95%), surrounded by copper (5%).

Yesterday I learned about "secondary enforcement" in the US: You can break a law (such as not using a seat belt) in some states, and it is perfectly fine even if a police officer sees you - as long as you don't break a different law at the same time (such as speeding) you get away with it. Why is there no wikipedia page about that concept?

 

[DennisN]

Today I learned that the newly installed Windows 10 occupied 25% of the total storage space on my tablet, which made me feel like

...so I reverted back to the considerably smaller Windows 8.

 

[OmCheeto]

Today I learned that the newly installed Windows 10 occupied 25% of the total storage space on my tablet, which made me feel like

...so I reverted back to the considerably smaller Windows 8.

My original computer had a Microsoft OS that occupied 8 kilobytes. (8 bits) (1980)
My first "PC" used Windows 3.1, which occupied 12.5 megabytes. (32 bits) (1995 ?)
I see that Windows 10 occupies 10 gigabytes. (64 bits) (2015) (Comparable to my Yosemite OS @ 8 gigs)

So TIL, that if you include bit size, modern OS's are 5,000,000 times larger than my original computer.
That's kind of freaky.

This kind of reminds me of a thread I started the other day:

The internet, Physics Forums, and Dr. Neutrino [PF, circa 2008]

300 Gb? I picked up a 300 gig for $100. Try multiple terabytes! Check out the HP Blackbird, friggin' insane comp!

Are those 32 or 64 bit bytes?
My January '75 Popular Electronics magazine said that 256 bits of memory were worth about $1.75. A one terabyte drive at 32 bits per byte would have been worth over $200 billion back then. wow.

 

[mfb]

A byte is always 8 bits. Bytes are not words. Words increased in size, bytes did not.