Hi everyone and welcome to the new Megathread :) For my first Mega I want to share a special interest of mine: the magnetic field and how to understand its behavior intuitively.
I'm guessing most of us have played with magnets before at some point and have felt that mysterious force pushing them apart or pulling them together, depending on how the magnets are oriented toward each other. Some of you may have also seen diagrams like this (By Geek3 - Own work,This file was derived from: Ironfilings cylindermagnet.svg This file was derived from: Magnet compasses.svg, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=88524982)
Or done an experiment where you visualize the magnetic field lines with iron filings like this (Public domain, Newton Henry Black, Harvey N. Davis (1913) Practical Physics, The MacMillan Co., USA, p. 242, fig. 200)
These lines represent the shape of the magnetic field. The way you can interpret them is that if you place a compass in the field, the compass will align with the field lines at that point. And the closer the lines are to each other, the stronger the magnetic field is in that area. Also, magnetic field lines always form closed loops. They appear to end at the poles of a magnet, but actually they continue on inside the magnet. They do however exit/enter the magnet at the poles.
"But Witchy," you may ask, "why are the lines so concentrated at the poles but then they spread out so much as they travel from one pole of the magnet to the other?" Excellent question my theoretical student XD.
This is I think the key point that was a bit of a eureka moment for me when I realized it a long time ago when I was studying this stuff: the magnetic field lines "want" to be as short as possible while also "wanting" to be as far apart as possible. And when I say want, it does actually behave a little bit like a desire, as the magnetic objects in this field will experience a magnetic force tryin gthe move the object to spread out the field lines and make them shorter.
Let's use this picture I grabbed from Wikipedia as an example: (By Geek3 - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=10555891)
the bar magnet creates a strong magnetic field at the poles, which means lots of magnetic field lines are squeezed closely together at the poles where they enter/exit the magnet. These lines don't want to be so tightly packed together, so they immediately start spreading out but also immediately start curving towards the opposite pole to try to keep the distance short. If you then try to bring the north pole of another bar magnet close to the north pole of this one, both have magnetic field lines coming out trying to get to their respective south poles, but now even more tightly packed together as you bring the magnets together. Since the magnetic field lines don't want to be so close together, both magnets experience a force pushing each other away so that the magnetic field lines aren't being pushed together so tight.
Similarly, if the south pole of one bar magnet is brought near the north pole of another, the magnetic field lines exiting the north pole of one want to go to the south pole, but the closest south pole is the south pole of the other magnet being brought close, so now the lines go through both magnets before looping back around: (By Geek3 - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=10515628)
However, between the closest poles of the two magnets, the lines are still concentrated but will try to spread out between the poles. Since the lines want to be as short as possible and don't want to spread out, the magnetic field exerts a force on the bar magnets pulling them together, since that would shorten the lines between the poles down to pretty much nothing.
Finally, a few of you may have been wondering what determines how much the magnetic field lines want to spread out vs shorten. These two tendencies are in opposition pretty much all the time, since spreading the lines out more requires making them longer. This is determined by something called the magnetic permeability which is a property of the materials that the field is passing through (even air or a vacuum). High permeability materials tend to concentrate the magnetic field lines more and allow them to get shorter, while low permeability materials tend to force the lines to spread out and lengthen. Examples of materials with high permeability are iron, cobalt, and other magnetic or ferromagnetic materials. Low permeability are pretty much anything that doesn't experience force in a magnetic field, so most things.
Post thumbnail attribution: (By Omegatron - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=640068)
Anyway I hope some of you enjoyed this rant or find the information here useful. I can talk about magnets all day so feel free to hit me up if you want, though my inbox will be overflowing for the next week I'm guessing.
Enjoy the Mega!
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As a reminder, be sure to properly give content warnings and put sensitive subjects behind proper spoiler tags. It's for the mental health of not just your comrades, but yourself as well.
Here is a screenshot of where to find the spoiler button.
I don't think I can link PDFs so here's a screenshot of it (lol)
relationship thing
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I totally agree, I found that getting off of the normative "relationship escalator" was key to starting to understand myself and what I want.
I don't know if you can relate to this, but I am not actually sure I'm introverted, but extremely socially anxious. I think deep down I find people and connecting with them highly recharging for me, and I want to be around them. But for most of my life, I thought I was introverted because I was around neurotypical people or people I had nothing in common with, which was draining. I've had a few social interactions lately that do feel right to me, and I found them invigorating.
gah same i self-censor so much but if someone takes an interest i will open the FLOODGATES. It's so bad I'm not even sure what my own interests are sometimes!
oh don't even get me started ;_; i have regular problems with this, feeling like if I'm feeling bad things or if I have needs I'm imposing or being a burden... it's so difficult... sometimes it feels hopeless to try and build self-confidence but I'm lucky at least to have people reassure me. And I can always infodump here on bearzone if I really need to, that doesn't feel like imposing on people because they can just not read it!
gah that sucks so much. I mean, some people are just kinda bad people, and a lot of times it takes time and effort and many failures to find the good ones, who don't just tolerate but instead cherish you, flaws and all. I'm working on it too. Maybe we can keep chatting sometime.
I mean it was a provisional one anyway, I have a complicated history. But I'm still pretty sure I'm some form of demi.
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This image is a godsend omg. I will be pondering over this for the next little bit for sure. I feel like just skimming over it is giving me lots of actual tangible things to think about. This is great. I had never heard of the "relationship escalator" before, but I looked it up and I think stepping off that is exactly what I need to be doing. Figuring out what that means for me is a whole other thing of course, but the mere idea of it already feels so freeing.Another thing I might have to ponder on because thinking about it, there is a nonzero chance that's me as well. I do really love people and being around them so much, when it clicks. It's somewhat rare that it clicks, but when it does, I do come away from it feeling very refreshed.
I think I'm so good at self-censoring that I hide my thoughts from my own self. But you want to talk about floodgates, I still think about the time one of my friends asked me a question about something, and I proceeded to go on this GIANT 3 hour long nonstop monologue. A bit later he sends me a message along the lines of "omg I promise I'll read this later but I can't right now" and he attaches a screenshot of his phone screen with discord showing like 200+ unread messages, all from me lmao. I have such immense infodump potential that it's like a nuke goes off if you hit the right thing and I'm comfortable enough around you. Makes me feel kinda bad though 'cause maybe it's a bit overboard.
Yeah I figure as much. I'm trying to work on it though
I'd very much be down. I'm a big chatter hehe
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I felt exactly the same way... glad I could help!! Might help to fill it out for a prospective partner, or the people in your life, you don't have to share it if you don't want to, but may just help having an idea.
:) totally!!
been there, although I find these days mine are actually a bit shorter than they used to be, though, and i'm not sure why? I guess maybe because I am able to get them out sooner...? It sure does feel good to get those thoughts out sometimes though when they start to pile up.
:)
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I've been thinking about it for a hypothetical future partner for now just to get my brain juices going. I mean nothing's set in stone so I can always reevaluate if and when things become more real
I think that's what it is for me. I haven't done a 3 hour session like that in a while, and I think it's just because the frequency of them has increased. I can get it out of my system better haha
My matrix user is @yewler:genzedong.xyz if you want to chat :) And also anyone else who stumbles across this is totally welcome to say hi! As previously established, I like chatting, but the tracha overwhelms me