Anyone have any random nerdy facts?

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Battery sizes for coin type Lithium.
CR2030 for example. Coin Round. (coin shaped and round)..... Last 2 digits are thickness in 0.1mm increments. Leading digits are diameter in mm.
so Coin Round 20mm dia 3.0mm thick.
SR is Silver chemistry Round. Same but 1.55V usually for watches or old cameras..... SR726 would be 7mm 2.6mm thick silver chemistry.
The LR44 would be an exception...... Commonly used for electronic digital verniers.
So now you just have to buy a LR44, put it in your verniers and measure the battery in your watch with some weird number on it and search on Ebay for SR(Dia)(Thickness to 2 sig digits and multiply X10) if it's a small one or CR if it's a big one Lithium.....Simple....
LR44 is a hold-over from a less formalized naming, I assume assigned by manufacturers. There are similar alternate names for many sizes, but only LR44 has really held on.
 
Hydrogen is the most abundant element in the universe, but not on Earth due to its light weight, which allows the gas to just float off into space.
According to Bing.
And the second most abundant element in the universe, helium, is super scarce on Earth for same reason combined with the fact that none of it is bound up in heavier molecules.
 
Only three specific isotopes of any element have their own unique names. 3H is called tritium, 2H is called deuterium, and 1H is called protium.
 
(One more from the world of the elements.)

In general, the elements we call radioactive, those with no stable isotopes, are all of those above lead (element 82). But there are two elements below lead that also have no stable isotopes: promethium (element 61) and technetium (element 43).
 
Super conductive materials placed in a magnetic field exhibit a phenomenon called Quantum Locking.



It basically is suspended in the magnetic field but not necessarily confined to its position in the magnetic field so it can follow a track of magnets.
 
Super conductive materials placed in a magnetic field exhibit a phenomenon called Quantum Locking.



It basically is suspended in the magnetic field but not necessarily confined to its position in the magnetic field so it can follow a track of magnets.

Yup super cool, I like to think of it as magnetic drag.
 
Yup super cool, I like to think of it as magnetic drag.
My all time favorite weird physics phenomenon for sure. It really makes your imagination run wild with ideas lol.

E: Probably wouldn't be the best use for it, but if it were practical... and affordable, imagine using quantum locking to make a no-drag/no-friction rail launch system (not to be confused with a rail gun.. similar parts involved but different concept and goal). Do away with flyaway launch adapters all together. I'm sure this is less this practical in real life, but its just cool to think about
 
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E: Probably wouldn't be the best use for it, but if it were practical... and affordable, imagine using quantum locking to make a no-drag/no-friction rail launch system (not to be confused with a rail gun.. similar parts involved but different concept and goal). Do away with flyaway launch adapters all together. I'm sure this is less this practical in real life, but its just cool to think about
Like the fact that rockets that use fly aways are usually launched from the desert where liquid nitrogen is in short supply…
 
I like to imagine there is a gas station along a random road in the desert that has a fuel pump of L-NO2, complete with the guy in overalls on a rocking chair who judges you for being a "city-slicker" lol
 
At least on one occasion, the entire earth was covered in ice = snowball earth.
Fun fact about this: its theorized life lived through snowball earth by living in little cavities/bubbles from dark rocks melting into the surface of the ice to create little warmer than freezing microbiomes. (Something I learned from PBS Nova). As he is so famously quoted:

findsaway.gif

I highly recommend their ancient earth series. They have a whole video about how siberia was once an active super volcano for like millions of years; it was one of the mass extinction events.
 
Most of the time you say the number of neutrons eg He^3 so it’s a standard notation but this time it’s a name and it drives me crazy having to say (and spell) deuterium and the others.
You can still say or spell it as hydrogen-2 or 2H if you like.

(And it's not the number of neutrons, it's the number of nucleons. But I'm pretty sure you know that.)
 
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No it’s neutrons, see just before the diagram, Wikipedia.
Below is the diagram (annotated by me) and here is the caption with that diagram:
The three naturally occurring isotopes of hydrogen. The fact that each isotope has one proton makes them all variants of hydrogen: the identity of the isotope is given by the number of protons and neutrons. From left to right, the isotopes are protium (1H) with zero neutrons, deuterium (2H) with one neutron, and tritium (3H) with two neutrons.
1713301629928.png
 
I guess so it’s just that it has always been explained that way even in text books so I don’t feel bad.
You are definitely confusing the words "neutron" and "nucleon," and if your textbook is mixing it up as well, you need to bring it up with your science faculty. That is not a trivial error.
 

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