I bought 1000 meters of wire to settle a physics debate

What Hacker News said

Strong rec jerf · 2023-09 · on “How the Most Useless Branch of Math Could Save Your Life”

The video in question for reference: [LINK] Interestingly, when I saw that I figured this channel for a goner because he was going to turn to the darkside, but quite contrary to expectations I feel like his channel has actually blossomed since then. His older videos are fine, but often just explaining concepts that you can find a lot of other explanations on, but some of his recent videos have rocked the boat even among physicists and IMHO he was ultimately proved to be correct for them. I particularly point at his videos about how nobody has measured the one-way speed of light ( [LINK] ), which was well-known among people very very deep in the field of relativity but not very well known out

Strong rec moffkalast · 2023-12 · on “Veritasium: The SAT Question Everyone Got Wrong [video]”

Yeah I really liked the AlphaPheonix video[0] where he actually built the thing in a field and explained the entire effect properly. I'm not entirely sure if Derek didn't really understand what he was presenting in that video or deliberately based it on a really misleading bullshit gotcha to troll people and stir debate for clicks, and neither reflects very well on him. [0] [this video]

Strong rec reaperman · 2024-07 · on “Mechanical computer relies on kirigami cubes, not electronics”

[this video] AlphaPhoenix did an amazing experiment to measure the speed of electricity FWIW. His other videos are incredible as well and explain EM physics in an absolutely outstanding way.

Recommends pja · 2022-01 · on “5.5 mm in 1.25 nanoseconds”

His presentation is not very clear & imo the way he answers the question is not actually helpful in actually understanding what’s going on, but he is correct that current will flow in the far side almost immediately. As is made clearer in the documents he shared which contain his discussions with actual physicists, that current will be much smaller than the final current that flows all the way round the circuit, but it is there nevertheless. (In fact that current will initially flow whether or not the two halves of the flat ring are connected - if you think about it things have to work like this, because the middle of the system cannot “know” whether the far ends are connected until light ha

Recommends bertil · 2023-04 · on “How do electrons find the “Path of Least Resistance”? [video]”

The author has a fascinating video (part of a wider effort of many science YouTubers) that tries to clarify all that. [this video] I’m actually not sure if that makes his explanation more accurate because it’s informed by that, or more regrettably forced metaphor. But the whole series of videos from different creators is worth watching if you want to understand the whole “electrons are moving” thing.

Recommends Manuel_D · 2023-07 · on “U.S. Marine Corps Antenna Handbook (1999) [pdf]”

Not really in the intuitive sense: [LINK] Someone actually went out and tested this: [this video] The electric field is very tightly constrained around the wire. The amount of energy that reaches the light through the gap is incredibly small, not nearly enough to turn on a real light bulb. The bulk of the energy does indeed have to take the path through the wire. I find that video usually leads people to an even less correct understanding than the marbles-in-a-tube analogy. The Veritasum video can essentially be summarized, "fun fact: two parallel wires act like an antenna, and an extremely small amount of energy reaches the other end before the rest of the energy takes the long path through the

Recommends Spivak · 2025-02 · on “But good sir, what is electricity?”

Yes, you can see one of the best people do a demonstration of it [this video] It's close enough to c that you should just use c but it can be observed that it's less.

Recommends sbuttgereit · 2026-04 · on “Any Color You Like: NIST Scientists Create 'Any Wavelength' Lasers”

Looking at the discussion below this comment, I'd just add this video by AlphaPheonix: [this video] Good discussion in the comments there as well.