16.4M views · Mar 14, 2023 · 23:05 · 0 HN recommenders · 4 mentions · discussed 2023–2024
Veritasium visits the National High Magnetic Field Laboratory to see the world's strongest magnets and demonstrate effects like eddy currents. It covers what intense magnetic fields do to materials and objects.
Why Hacker News points people here: Cited as a reference for magnet safety, eddy currents and superconductor levitation in physics threads.
“he talks about how and why superconductors levitate.”HN comment, 2023
“my "strong magnets aren't lethal to people" knowledge is based (in part) on a Veritasium YouTube video”
Visit to world's strongest magnet showing strong magnets aren't lethal
I'm not the person you're responding to, but my "strong magnets aren't lethal to people" knowledge is based (in part) on a Veritasium YouTube video[0] where they visit the "World's Strongest Magnet" and do shenanigans. [0] this video
“he talks about how and why superconductors levitate.”
Shows eddy currents and why superconductors levitate
Eddy currents can be induced in non-superconducting materials that make it look like levitation, but the catch is that there has to be relative motion between the magnet and the object 'levitating' to generate the currents in the first place. I've linked to a relevant example in a Veritasium video here: this video But in this sample video, the standoff distance doesn't appear to be slowly dropping at all, which would rule out eddy currents as a source of the behavior. If you continue watching the linked video to 13:27, he talks about how and why superconductors levitate.
“here is a summary video [5]”
Summary video on diamagnetism
> Not sure why this is getting such a negative response We're hackers. Newness is enticing. Complaining that you're "getting tired" of something because it's novel while asking for a TikTok summary is lazy. As another commenter mentioned, start with Wikipedia [1]. From there one sees apatites (think: hydroxyapetite or flurapetite on your teeth) [2]. Searching Google Scholar yields this paper about lead apatite [3][4]. We also see the Wikipedia article talk about diamagnetism; here is a summary video [5]. And here is a promising paper [6] from the Wikipedia entry on quantum wells [7]. I'm currently stuck here: I don't get quantum wells, and don't see--intuitively--how an apatite (or a misformed one) could produce them. In summary, asking for help is always welcome. Complaining about your ignorance and lack of motivation, seldom so. [1] link [2] link [3] link [4] link [5] this video [6] link [7] link
“Bullet would just orient itself to minimize eddy currents.”
Demonstrates eddy current effects on objects in strong magnetic field
Not really. Bullet would just orient itself to minimize eddy currents. People would start using thin disc shape bullets that would slide through the magnetic field without much trouble after orienting themselves in the best direction. this video
