What did you learn today?

  • Thread starter Daniel Y.
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  • #1
Every day I would come home from school and my sister would ask me, "what did you learn today?" Sometimes I'd stammer and tell her I hadn't learned anything useful, while other days I'd happily tell her I read Phaedo or learned what an isotope is. In the 'Does your interest in learning cease at a certain age?' thread jimmysynder reminded me of this old tradition we had.

So today, tomorrow, and any day you get the chance, post something you learned. Anything from a new physics equation to a new word - whatever it is regardless of how technical or simple. I'll start.

Today I learned how to measure how big the Earth is using only the sunset when I'm laying down and when I'm standing.
 

Answers and Replies

  • #2
grafica
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hi
jun 5- world environmental day
 
  • #3
grafica
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the time taken for the light to reach Earth from sun is
just ONE second
 
  • #4
Astronuc
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  • #5
BobG
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I learned that my birthday falls during National Procrastination Week. I wish I would have learned that sooner.

the time taken for the light to reach Earth from sun is
just ONE second
That's true if you're also moving from the Sun to the Earth at 99.9% of the speed of light.

Well, at least according to your clock. Astronuc's clock might disagree if he's just lollygagging on Earth.
 
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  • #6
Howers
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I learned that the first day of summer this year is on the 21st.
 
  • #7
Santa1
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Following BobG's birthday discovery I self looked into if anything interesting happened on my birthday, and indeed it did! I have the same birthday as J.R.R. Tolkien!
 
  • #8
mgb_phys
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I learned that my birthday falls during National Procrastination Week.
How did get around to setting the date for that?
 
  • #9
How did get around to setting the date for that?

They sent out a survey asking respondents to pick a week. The procrastinators never got back to them, so they got what was left over.
 
  • #10
BobG
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Following BobG's birthday discovery I self looked into if anything interesting happened on my birthday, and indeed it did! I have the same birthday as J.R.R. Tolkien!

Wow! You've got a lot better birthday than me. On my birthday, Thomas Edison didn't invent the movie camera; Osama Bin Laden was born; some jerk of a boss said, "Come here, I want to see you" on the phone for the first time; the NASDAQ peaked at 5132.52 and the dot.com boom started its crash; and some scientist told me, "There's rings around Uranus."

It almost makes me embarrassed to wear a T-shirt with my birthdate (Julian date {except for leap years}) on it.
 
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  • #11
grafica
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hai
world pie(22/7) day is march 14
 
  • #12
Today I learned about general and special relativity, it was really exciting, I think most of the physicists when they get old, they remember times like these ~ learning new stuff.
 
  • #13
Cyrus
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I learn at least 10 new facts every day. But it would be too much time for me to type it all.
 
  • #14
BryanP
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I learn at least 10 new facts every day. But it would be too much time for me to type it all.

Truth.
 
  • #15
Moridin
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Today, I learned that the there are significant sequence homology and functional similarities between the type-II secretory system, the type IV-pilus and the archaebacterial flagellum.
 
  • #16
G01
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Today I learned about general and special relativity, it was really exciting, I think most of the physicists when they get old, they remember times like these ~ learning new stuff.

I disagree. I may be a young guy myself(rising college senior), but it seems to be the greatest part about being a scientist is that there is always new stuff to learn, no matter what stage of your education your at.
 
  • #17
Cyrus
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Maybe I am alone on this one, but I don't get 'excited' to learn anything. I just like learning things, but I don't go 'yes, now I am learning (x,y,z)!'. I just go, 'ah, that's interesting....NEXT'.

The only time I get 'excited' is when I am able to see something working in the real world and go, 'ah, this is a _fill_in_the_blank". I know all about this. Why this was designed this way, and not that way. etc, etc. Or who designed it, and what it means.
 
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  • #18
Today, I learned that the there are significant sequence homology and functional similarities between the type-II secretory system, the type IV-pilus and the archaebacterial flagellum.

Now that's just showing off :rofl:
 
  • #19
Jimmy Snyder
1,095
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The expected absolute value of the sum of the signed displacements of m random walkers after n steps is the same as the expected absolute value of the displacement of 1 random walker after n x m steps.
 
  • #20
turbo
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I learned that a truck bumper that has rotted braces on one side can have LOTS of healthy metal in the braces on the other side, requiring a lot of sawing to sever. Luckily, I have 18V Makita power tools and had a still-usable metal blade.
 
  • #21
maverick_starstrider
1,115
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I learned that the bottle of water I bought from the store had a hole in it. This consequently led to the revelation that water and paper don't mix. And finally I learned that when I return this book on monte-carlo simulation to the library I may have to pay a fine. All in all it's been a pretty informative day.
 
  • #22
Jimmy Snyder
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And finally I learned that when I return this book on monte-carlo simulation to the library I may have to pay a fine.
Maybe not. I borrowed a library book to take on a camping trip. This was when Hurricane Agnes hit. The book was partially moist and thoroughly soaked. I dried it out and brought the amazing looking thing back to the library to assess the fine. They took the book back and told me not to worry about it.
 
  • #23
Evo
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Adolf Hitler commited suicide on my birthday, a few years ealier though.
 
  • #24
turbo
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He knew you were coming.
 
  • #25
hypatia
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I learned that at 51, if you drink and think going down a jello slide, which is on the top of a double decker bus, is going to be fun. That you really need to re-think what your idea of fun really is.
 
  • #26
I learned that after 60 year parents can go nuts.
 
  • #27
Moridin
688
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Adolf Hitler commited suicide on my birthday, a few years ealier though.

My mom shares Hitler's birthday.
 

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