Today I Learned

  • Thread starter Greg Bernhardt
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In summary: Today I learned that Lagrange was Italian and that he lamented the execution of Lavoisier in France during the French Revolution with the quote:"It took them only an instant to cut off this head and a hundred years might not suffice to reproduce it's...brains."
  • #1,786
Pulling the hair which has a diameter of 40 µm, 40 times.
 
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  • #1,787
Today I learned that there is/are natural nuclear fission reactor? At first glance I thought I was reading fusion (reactor), sun, stars. But it was fission.
Hmm.., I think it should be a very big ore with high uranium concentration.
https://en.wikipedia.org/wiki/Nuclear_fission
 
  • #1,788
I learned that cancer-causing mutations in the elderly get accumulated more than those in the young.
However true or false it turns out, leading a happy life is important. Enjoy! :biggrin:
 
  • #1,789
fresh_42 said:
As if you knew how thick his thumb is.
There are men whose thumbs look long, skinny and pointed. Luckily mine isn't and I prefer thick ones.
OmCheeto said:
...
Did you know, that when I was born, only 5% of Americans thought mixed race marriages were ok?
I found this out just a few months ago, and was like; "What?? Really? Wow."
Serious ? are people in your area still racist or against same sex marriages ?
Personally I think Yes, especially those of over 50s.
Racist thoughts are learned and rooted in people's mind. Removing them is like a requirement to either brain-wash or cancel out some of their hosts' neuronal functions.
 
  • #1,790
Pepper Mint said:
Serious ? are people in your area still racist or against same sex marriages ?
...
Not that I can tell. Although black people only comprise 6% of my city's population, Obama received 75% of the vote in both general elections.
And I don't think many people around here have a problem with gay marriage. Our last mayor was gay.

I was born nearly 60 years ago, and that 5% statistic regarding interracial marriage was from a nationwide USA poll. [ref: Gallup]
 
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  • #1,791
TIL that the radiation resistance of tardigrades (AKA water bears) is probably due to a specific DNA associated protein.
And that the gene when transferred to human cells in culture also increases their radiation resistance.

Next step in my plan for space dominance, breed up some recombinant astronauts for those long high radiation journeys to other planets.
 
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  • #1,792
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  • #1,793
Today I learned that Tsar Bomba only lost 2.7 kg of its mass?
http://physics.stackexchange.com/qu...is-the-percentage-of-mass-converted-to-energy
That's why they can display the rest of the bomb in a museum. :smile:
Tsar Bomba - small.jpg
 
  • #1,794
Today i learned that those who want to work are mixed with ones that do not want to work, i am fed up hearing of people with (bad backs and finger aches) that do not want to work, where as i have a minor mental issue and am 65 and want to work.
 
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  • #1,795
wolram said:
Today i learned that those who want to work are mixed with ones that do not want to work, i am fed up hearing of people with (bad backs and finger aches) that do not want to work, where as i have a minor mental issue and am 65 and want to work.
Wolram, if they don't want to employ you in a regular full time job, have you thought about online part time job?
Either in your field or maybe teaching English?
I'm not sure if talking is helping or stressing to you. Each person is different, so this may be a good idea only in case that you are comfortable with talking.
There are many agencies that do this. I'm sure many people would pay to speak with a native speaker and this human contact could be good for you, too. What do you think?
 
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  • #1,796
Sophia said:
Wolram, if they don't want to employ you in a regular full time job, have you thought about online part time job?
Either in your field or maybe teaching English?
I'm not sure if talking is helping or stressing to you. Each person is different, so this may be a good idea only in case that you are comfortable with talking.
There are many agencies that do this. I'm sure many people would pay to speak with a native speaker and this human contact could be good for you, too. What do you think?
I do not want to derail this thread, but i think learning of deep sociological injustice is pertinent to this thread, I think society should be split into three divisions
thoughts who are willing and able to work should have a privileged life stile, thoughts who are disabled and can not work should have a comfortable life and thoughts
That do not want to work should live on the bread line.
 
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  • #1,797
wolram said:
... willing and able to work ...
"Work" covers a huge range of possibilities. I don't like my job (IBM mainframe software support) but I do it because I need the money and I happen to have the right skills and experience to be very valuable in that specific job and hence to be paid relatively well. However, I also work hard (for no pay) for the amateur orchestral society (registered non-profit) which I help to run, which I mildly resent but consider reasonably worth while, and what I'd really like to have the time for is to work on finding better ways to understand many aspects of physics, and perhaps eventually to make some theoretical progress as a result.

But if you want to discuss that any more, I suggest starting a new thread. And your spelling of "those" is somewhat unconventional.
 
  • #1,798
Jonathan Scott said:
...
But if you want to discuss that any more, I suggest starting a new thread.
...
Well, that doesn't appear to have gone over well:

https://www.physicsforums.com/threads/should-we-split-society-in-to-three-groups.887978/#post-5585296
(You have insufficient privileges to reply here.)

:oldconfused:
 
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  • #1,800
TIL that there are microbes in a South African gold mine can feed off of the effects of radiation on the chemicals around them.
This implies similar organisms could feed off of cosmic rays and could result in expanding the environments where life might be found.
 
  • #1,801
Cosmic rays are quite rare compared to terrestrial radiation, and it is unclear if life can form if there is just this energy source. They are still water-based, and every place with liquid water is considered as place for life already.
 
  • #1,802
BillTre said:
TIL that there are microbes in a South African gold mine can feed off of the effects of radiation on the chemicals around them.
This implies similar organisms could feed off of cosmic rays and could result in expanding the environments where life might be found.
My first thought has been: Wow, wouldn't that be useful for our nuclear waste problem?
 
  • #1,803
How? They just use ions as energy source. That doesn't influence the chemical composition or activity of the material in any way.
 
  • #1,804
Sure, but maybe enough of them could reduce heat and necessary shielding, in the sense of shortening the range of radiation.
 
  • #1,805
They don't violate energy conservation either. The chemical energy they produce is absolutely negligible compared to the overall heat production. And they do not reduce the radiation length. They increase it compared to heavier elements.
 
  • #1,807
Buzz Bloom said:
TIL (actually yesterday) that Stephen Hawking is hawking jaguars.
I heard that the other day, too.

I love Stephen's excuse, as, it sounds so, um, human:

“You all know me as Professor Stephen Hawking, the physicist wrestling with the great concepts of time and space. But there is another side to me that you may not know: Stephen Hawking the actor. I have always wanted to be in a movie playing the part of a typical British villain. And now, thanks to Jaguar my wish has come true.” -Stephen Hawking

Thank you, professor Hawking.

Many of us, are on the other side of the bridge, wanting to be, as brilliant as you.
 
  • #1,808
I have a lifetime gym membership for a fitness center 600 miles away in another state that I haven't been to in years. Every once in a while I check to see if they have expanded to where I live now. TIL that they went out of business two years ago. :wideeyed:
 
  • #1,809
Borg said:
lifetime gym membership
For the lifetime of the gym.
 
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  • #1,810
Borg said:
I have a lifetime gym membership for a fitness center 600 miles away in another state that I haven't been to in years. Every once in a while I check to see if they have expanded to where I live now. TIL that they went out of business two years ago. :wideeyed:
Lucky you, that you hadn't

to find out!
 
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  • #1,811
Today I learned the reason patients should take their Coumadin dose in the evening. Makes sense when it was explained.
 
  • #1,812
Re-reading my General Physics book...

I re-learned a useful tip: to keep one hand on my pockets (if I have) when another touches electricity. To avoid electricity from using my body to make ground. It's a little mini section on the book talking about electric hazards. The book is: https://www.amazon.com/dp/0131992260/?tag=pfamazon01-20

Chapter 26.
 
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  • #1,813
Psinter said:
keep one hand on my pockets (if I have) when another touches electricity. To avoid electricity from using my body to make ground. It's a little mini section on the book talking about electric hazards.

Sounds like a practical physics book.

Old timey electricians 'feel' first by brushing with the back of their hand or fingers not the front . That's because electric current makes your muscles contract.
If you contact with the back of your hand that'll pull your hand and fingers away from the source. Don't ever touch it so that contracting muscles would wrap your fingers around it for you won't be able to let go.

It's counter-intuitive. We usually feel with our fingertips , but when 'back of the hand' was explained to me by an old lineman it made so much sense i quickly formed the habit.

Maybe that's in your book too.

Anyhow - thanks for sharing. Awareness of details like that saves lives .

old jim
 
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  • #1,814
mcknia07 said:
Today I learned the reason patients should take their Coumadin dose in the evening. Makes sense when it was explained.
Why should they?
 
  • #1,815
Today I learned that the Chicago Cubs were not the first occupants of Wrigley Field. That distinction goes to the Chicago Whales.

(Whales? in Chicago? o0))
 
  • #1,816
jtbell said:
Today I learned that the Chicago Cubs were not the first occupants of Wrigley Field. That distinction goes to the Chicago Whales.

(Whales? in Chicago? o0))
You're not the first who asked:
http://www.lansingstatejournal.com/story/travel/2016/03/31/heres-whopper-whale-watching-lake-michigan/82473438/
 
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  • #1,817
aa said:
Why should they?

It's so that if a doctor has to adjust their dose after blood work they can get the correct dose in that same day. Plus, if you take the dose in the morning it will change the INR levels and not reflect a true accuracy of the levels in the blood.
 
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  • #1,818
Today I learned (following up something I read online) that my phone camera sees a bit of infrared. In particular, it sees the output from my TV remote control as a purple glow even though I can't see it directly. Apparently the sensors are sensitive to infrared but the camera has a thin filter which is supposed to cut most of it out.
 
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  • #1,819
Jonathan Scott said:
Today I learned (following up something I read online) that my phone camera sees a bit of infrared. In particular, it sees the output from my TV remote control as a purple glow even though I can't see it directly. Apparently the sensors are sensitive to infrared but the camera has a thin filter which is supposed to cut most of it out.
I knew that but had never done a demo. That's pretty neat...
 
  • #1,820
That's a handy way to check whether a remote is working.
 

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