I'm currently learning about Electron Configurations and specifically Electron Penetration and Shielding in my college chemistry course. Up until now, the course has been review, but now it's beginning to contradict what I learned in Accelerated Chemistry in high school. The text's explanation simply states that a 2s orbital is closer to the nucleus than a 2p orbital, so the remaining electron resides there.
I would think that as a Lithium 2 ion, first the single electron in the 2s orbital would be removed, followed by one of the electrons in the 1s orbital, leaving one electron in the 1s orbital. I understand this is incorrect. Why?
I know, I know; this is a shameful gap in my knowledge as an upper division science student, but I couldn't immediately come up with the answer, and my notes from gen chem contained little that I didn't think would be tested (a pox on younger me).
I realize the mean radius of a 1s orbital will be stupidly small, but is there some hard measurement in angstroms for say, a hydrogen's electron lower bound?
Hi, would anyone perhaps know
why is the average transitional time of electron from 2p orbital to 1s (~10-9 s) smaller than of an electron from 2s orbital to 1s (~10-1 s) in Bohr's atom?
The energy difference is obviously greater in a jump from 2p to 1s and does that mean that the time must be smaller because of the uncertainty principle or not since the uncertainty principle deals in uncertainty of energy and time and not in the quantities of those?
Hey all, I'm getting started with collecting 18650s and I've been slowly going around retrofitting my electronics to take 18650 packs instead of the alkaline aa/aaa and 9v they usually take. I live in a humid place and my alkaline cells always leak. For example, my label maker, It takes 8x aa cells. I want to simply plug in a 3s pack whenever I use the label maker. My weather station takes 3xaaa. I want to have it hooked up to a 1s pack. Motion light takes 6 x aa. I want to have these packs ready and charged so I don't need to wait to recharge. But the question is, what is a good connector to make this safe and easy? Some things I have set up with xt60 but I prefer something smaller and cheaper. Something I can buy in bulk on aliexpress. Most of my applications will be low current.
Thanks a lot!
I don't want to step on anybody's toes here, but the amount of non-dad jokes here in this subreddit really annoys me. First of all, dad jokes CAN be NSFW, it clearly says so in the sub rules. Secondly, it doesn't automatically make it a dad joke if it's from a conversation between you and your child. Most importantly, the jokes that your CHILDREN tell YOU are not dad jokes. The point of a dad joke is that it's so cheesy only a dad who's trying to be funny would make such a joke. That's it. They are stupid plays on words, lame puns and so on. There has to be a clever pun or wordplay for it to be considered a dad joke.
Again, to all the fellow dads, I apologise if I'm sounding too harsh. But I just needed to get it off my chest.
Do your worst!
Hi, I'm back for this series.
TLDR version in the second last section
As I mentioned before, this series is intended to let us monyets here know more about Malaysia currently existing warning system, like flood warning, tsunami warning and for war and etc. But as mentioned in the last post I made [Existing Early Warning System in Malaysia for Flood, Tsunami and War], we will be focusing on siren type warning only. If you haven't read about Part 1, you can click the link above to know how does our flood warning system work.
If you read the news today, you may have come across a news about Tonga undersea volcano eruption and its subsequent tsunami in Pacific Ocean. Luckily, Malaysia will not be affected by it as stated in a statement by Malaysia Meteorological Department.
Statement by MetMalaysia regarding Tonga tsunami
____________________________________________________________________________________________________________
Ok, now let me get straight to the point.
Warning system name: Sistem Amaran Awal Tsunami Nasional Malaysia (SAATNM) [Malaysia National Tsunami Early Warning System]
Management agency: Malaysia Meteorological Department (MetMalaysia)
This tsunami warning system is set up since 2004, the Indian Ocean tsunami incident. Before that, Malaysia have never encounter any tsunami in modern history and this created an illusion that Malaysia ialah negara tiada bencana alam(ok, at least relatively speaking Malaysia is indeed a country with little natural disaster).
SAATNM tsunami siren electrical box
This system (SAATNM) constantly gather data from 77 seismic stations, 17 tidal gauges, 18 coastal cameras located at several coastal areas in Malaysia. This system will also collect data share
... keep reading on reddit ➡I'm surprised it hasn't decade.
It was the remake with Keanu Reeves, I discovered it was a remake through looking it up to make sure I got the title right. I believe it is appropriate for this sub and I want to say collapse is imminent. We enslaved the electron and thus have been enslaved by it. Our species is doomed to fail because we can't make the necessary changes to ensure our survival. We simply have not evolved enough to break free. Our financial system has gripped the world into a destructive path that is deeply rooted in greed and destructive practices that ravage the biosphere to a degree that will cause it to collapse. On Netflix's breaking boundaries: the science of our planet, they call attention to the holocene https://en.m.wikipedia.org/wiki/Holocene
On a side note it is really a remarkable documentary and it should definitely be watched. They bring attention to it because the earth's temperature closely follows the concentration of carbon dioxide in the atmosphere, it's my belief that there is no way for us to stop unless changes are made that people will not be willing to make. We simply are not evolved enough to understand nor are we compelled enough to significantly change the way we do things in order to save ourselves. It's not about some meeting of world powers and empty promises to pollute less, we're well beyond that. The fuse is already lit, the countdown begun, and some companies are talking about making changes that will allow them to be carbon neutral by 2050, as if the next 30 years will not devastate the planet more. To little too late. I'm going to take a tumble down a rabbit hole and I know I'll loose some of you but here goes. The virus reguardless of it's origin has helped us understand how much we rely on the system we're plugged into. It shows us how down right stupid we can be. It shows us currently how true the saying for want of a nail the kingdom has fallen is.
Long ago with our circumventing of natural selection we have laid the snare that has caused the human species to grow outside the ability of our habitat to sustain us. We are destructive, to ourselves, other species we share the planet with, and to our planet in general, through our misuse of natural resources. Take the American Indians as an example, when a tribe grew large and strong they expanded for want of land. This expansion led to war and a culling of the weak, the strong survivors procreate thus completing the circle. Sure they didn't drive SUVs and have phones to entertain them
... keep reading on reddit ➡For context I'm a Refuse Driver (Garbage man) & today I was on food waste. After I'd tipped I was checking the wagon for any defects when I spotted a lone pea balanced on the lifts.
I said "hey look, an escaPEA"
No one near me but it didn't half make me laugh for a good hour or so!
Edit: I can't believe how much this has blown up. Thank you everyone I've had a blast reading through the replies 😂
It really does, I swear!
The Conference
I was able to attend the DVN conference in Frankfurt, Germany earlier this week. Rather than publish information while directly at the conference, I wanted to have some time to review my notes and thoughts in order to create a more thoughtful and complete writeup. So, with an homage to Jack Handy, here are my “deep thoughts” on the DVN conference.
I got the impression the conference itself was not generally a "deal" conference per se, as much as it was a networking, mind-share, and marketing conference. The founders of DVN (Driving Vision News) originally started the conference which was focused on driving in poor lighting (nighttime) and bad weather. I got the impression it was mostly around head light technology, and again focused specifically around bad weather. Of course, LiDAR plays a broader role in both nighttime and poor weather driving; as such the conference creators are evolving and expanding. Most of the attendees (about 170) at the conference had deep knowledge of their particular area, and a high percentage were from Germany. For instance, many of the attendees that I met had a PhD in such areas as material science, or electrical, optical, and mechanical engineering. I got the impression that the actual buyers were not generally in attendance, but many experts and high-level influencers were there. Based on my experience attending conferences in a different market, this is exactly what I expected the conference to be. The format for the conference were presentations and panel discussions (Q&A). These were all done in one room, the networking at the booths was done at breaks and during the lunches and cocktail hour. There was also a networking dinner on Monday night.
The conference started at 1pm on Monday. I arrived around 12 noon. The lunch buffet was in the conference hallway, which is also where some of the sponsor booths were located. It just so happened that Microvision's booth was right next to the buffet. I saw a gentleman manning the Microvision booth and immediately introduced myself, it happened to be Dr. Luce.
Dr. Luce
We chatted for 20 minutes or so, during which time we were joined by a new hire - well actually, he does not start until February, but had taken some time away from his current job to begin his education process for Microvision. I won't mention his name, but he is based in France. Hiring in Europe is very different than the US. You can’t just give a two week notice to your
... keep reading on reddit ➡They’re on standbi
Pilot on me!!
I've always liked the idea of drones for years however my understanding was always "Well it costs a ton" and I never thought much about it beyond that.
Well... it doesn't. Not only that but I have more money than I did when I was 15 and initially interested.
My issue mostly comes down the issue of not knowing how to tell what would work with what.
Mostly with receivers. Certain things only work with other things but what the hell even is the difference between them? Are certain ones better or worse than others?
What the hell do I even look for when buying motors/FCs/controllers?
Whats actually worth it? What can be upgraded later in convenient ways that doesn't mean I have to replace a bunch?
Every single video i've watched, blog i've read, etc etc. Its all too short sighted or expects you to know a bunch of terms already.
Right now, if I want to build a drone.
I believe I need...
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motors, x4, duh.
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motor controller/power/supply/thing for each one, sometimes? I don't get this one, some have it some dont?
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FC - which does the actual controlling, I assume.
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Receiver - Because otherwise the remote is as fun as a brick
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Camera and transmitter - Seperate items, somtimes combined? Basically this only matters for the goggles and has to match that receiver type?
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Goggles - if FPV anyway, same as above.
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Controller - same as receiver.
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Frame
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Battery - The whole 1s 2s 3s was simpler and i've done electronics with stepping up/down stuff so I understood this better.
Am I getting a grasp on this at all? Am I over thinking things and should just grab matching transmitter/goggles and controller/receiver and throw shit together?
Is there an actual solid beginner set on amazon or something? What should it cost?
Is there anything special if you want to focus on indoor flying vs outdoors?
How tricky are they to fly? I've done a Dji Mini SE but far as i'm aware they're just straight up different in skill.
Hopefully this ramble isn't the dumbest shit you've read today. I just am struggling to know what i'm doing without doubting every step.
If you read through that trash then all I can do is apologize and hope you can say something to make all this click for me.
edit: Not sure it matters much but i'm capable with configuration of the FC stuff (from what i've seen in videos) and happy to tinker away at tedious issues for hours. Can also solder and have microcontroller experience to a beginner/medium level.
edit2: Love the respons
... keep reading on reddit ➡
I have not learnt much electronics but I do kinda know how the CPU works and how logic gates and all the higher level more abstract things work in a CPU.
I‘m really confused by this, some say 1 and 0 is the state of the transistor but that doesn’t make sense to me. I‘ve also read that it’s a high vs low voltage, but than isn’t voltage the electric tension between two points, which points would that be? I have always imagined the 1s and 0s or asserted and deasserted signals as high and low amperage, is that wrong?
Nothing, he was gladiator.
As 2021 draws to a close, we are once again presented with the opportunity to look back and see what this year had to offer musically. Much like last year, I will not be limiting myself to just power metal or even just metal, but will do the list in 3 categories. Feel free to just skip the ones you don't care for.
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BEST METAL ALBUMS - Mostly power and power-adjacent
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BEST NON-METAL ALBUMS
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OTHER INDIVIDUALLY IMPRESSIVE STUFF (Singles, Christmas specials, guest performances,...)
Big thanks to /u/JacksonWarrior for preparing the weekly releases and the guys who were kind enough to write "no recs from me this week" every week ;) Also to anybody irl and online who was kind enough to recommend stuff personally, I deeply appreciate you.
Alright then, we're staying close to home and kicking it off with maybe the most divisive category.
#BEST METAL ALBUMS OF 2021
Power metal is dying and/or already dead, so I combined all metal sub-genres into one list. In all seriousness, 2021 was perhaps the worst year for power metal in recent memory and I say that knowing that last year was poor enough to make me do a joint list.
Side-note: I talk about power metal a quite a bit, it's all European style power metal, American style power metal is poop.
This time we have a nice little mix of Power, Folk, Black and Melodeath. If an album made it to the list, I would whole-heartedly recommend it, as I left out a bunch of albums that were "aight". The best of the rest are mentioned in Honorable Mentions.
#Honorable Mentions
- Eons Enthroned - Into The Arcane - Power
- Phoenix Rising - Acta Est Febula - Power
- Ominous Glory - Power
- Wizardthrone - Melodeath
- Legend Of Valley Doom - Symphonic Power
#10. Seven Spires - Gods Of Debauchery - Power/Symphonic
For the second year in a row, Seven Spires make it to the album of the year post. Their previous album, Emerald Seas, was a massiv
... keep reading on reddit ➡Dad jokes are supposed to be jokes you can tell a kid and they will understand it and find it funny.
This sub is mostly just NSFW puns now.
If it needs a NSFW tag it's not a dad joke. There should just be a NSFW puns subreddit for that.
Edit* I'm not replying any longer and turning off notifications but to all those that say "no one cares", there sure are a lot of you arguing about it. Maybe I'm wrong but you people don't need to be rude about it. If you really don't care, don't comment.
When I got home, they were still there.
I won't be doing that today!
[Removed]
This morning, my 4 year old daughter.
Daughter: I'm hungry
Me: nerves building, smile widening
Me: Hi hungry, I'm dad.
She had no idea what was going on but I finally did it.
Thank you all for listening.
You take away their little brooms
What did 0 say to 8 ?
" Nice Belt "
So What did 3 say to 8 ?
" Hey, you two stop making out "
There hasn't been a post all year!
