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I bought 1000 meters of wire to settle a physics debate [video]

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Re: I bought 1000 meters of wire to settle a physics debate [video]

#41

Post by soneil »

lmilcin wrote: post #9

Fun to introduce general population to some interesting physics but please, don't call it "settling physics debate". There is NO debate. Not physics debate, not even practical debate because that knowledge is in practical everyday use. We know signals in wires take time to propagate and I have to take this into account when I design my circuits. Things like matching lengths of traces (especially differential pairs) s…

That's fairly intuitive. The lower current being present before the signal arrives is not intuitive.

Re: I bought 1000 meters of wire to settle a physics debate [video]

#42

Post by jstimpfle »

nathan_f77 wrote: post #26
umvi wrote: post #16

Earlier quoted context omitted.

200uA of current flows through the lightbulb instantly, but it doesn't reach full current until speed of light delay.

I don't think this is possible. If it were true, then you could add a transistor and an LED on the other side of the 1000M wire, and light up the LED instantly as soon as you press the switch. (Transistors and LEDs only take a few nanoseconds to turn on.) It's not possible to send any kind of signal or information faster than the speed of light.

Watch the video, read the other comments. The "instant" current flow comes from crosstalk. While the resistor and the battery are separate by 500m worth of ire on each side, they are actually located next to each other (so both places can be measured simultaneously).

Re: I bought 1000 meters of wire to settle a physics debate [video]

#43

Post by JshWright »

0xTJ wrote: post #5

That Veritasium video is one of the most controversial educational videos I've seen. I think one of the issues with it is that it's a bit pedantic, but also ignores other issues, that invites other people to be pedantic about it.

> I think one of the issues with it is that it's a bit pedantic, but also ignores other issues, that invites other people to be pedantic about it.

I think the video is intentionally misleading. He got a taste of how "successful" a controversial video can be with the "Wind powered car going faster than the wind" thing, and he's leaning into that. I just don't see any other explanation for how he chose to frame the problem.

Re: I bought 1000 meters of wire to settle a physics debate [video]

#44

Post by JshWright »

vexxed-concave wrote: post #8
0xTJ wrote: post #5

That Veritasium video is one of the most controversial educational videos I've seen. I think one of the issues with it is that it's a bit pedantic, but also ignores other issues, that invites other people to be pedantic about it.

True. It’s one of only a handful of YT videos I’ve ever left a comment on. In summary, just because something is “wrong” at one scale doesn’t invalidate useful models and workaday theorems at another. Also, for such a pedantic video his field lines were wrong.

> It’s one of only a handful of YT videos I’ve ever left a comment on.

Which was exactly his point— It's called "engagement".

Re: I bought 1000 meters of wire to settle a physics debate [video]

#47

Post by [deleted] »

soneil wrote: post #41
lmilcin wrote: post #9

Fun to introduce general population to some interesting physics but please, don't call it "settling physics debate". There is NO debate. Not physics debate, not even practical debate because that knowledge is in practical everyday use. We know signals in wires take time to propagate and I have to take this into account when I design my circuits. Things like matching lengths of traces (especially differential pairs) s…

That's fairly intuitive. The lower current being present before the signal arrives is not intuitive.

[deleted]

Re: I bought 1000 meters of wire to settle a physics debate [video]

#48

Post by frosted-flakes »

colechristensen wrote: post #3
csense wrote: post #2

I'm a big fan of AlphaPhoenix's content. He deserves to be in the big leagues of science YouTubers with SmarterEveryDay, Veritasium, Mark Rober and 3B1B.

I’m not a fan of the “big leagues” of science YouTube, many seem to have been tainted by the attention algorithm game.

Especially Mark Rober. His videos aren't really about science at all, but rather attention-grabbing feats like package thief glitter bombs, squirrel mazes, and chemical volcano explosions—pure entertainment. None of his videos teach you anything like Steve Mould's videos do.

Re: I bought 1000 meters of wire to settle a physics debate [video]

#49

Post by BHSPitMonkey »

NikolaeVarius wrote: post #29
Laremere wrote: post #25

Earlier quoted context omitted.

As much as I love Veritasium, I feel the OP video is better than his. Actually doing the experiment is really good, and it honestly feels like he was fishing for another debate like the faster than wind car by giving only a super theoretical and unintuitive explanation. (I don't have any real evidence of that, but it does /feel/ like it.) I also wonder what would happen if, instead of a setup like this: ┏───────light…

Yeah, this is what im wondering. The proposed mechanism for this is that the wires generate electric fields that influence electrons remotely. Fine. What happens when they are not close enough for any meaningful electric field interaction?

He says near the end of the video that a Part 2 video is forthcoming with more exploration of:

- Different sized loops

- Wires closer together / farther apart

- Wires on the ground instead of in air

- Current on both sides of switch

- Wires in two big spread-out loops

- Different strength resistors

Re: I bought 1000 meters of wire to settle a physics debate [video]

#50

Post by jbjbjbjb »

everybodyknows wrote: post #6

Anyone care to give us a Too Long; Didn't View?

Watch the animation starting at 17mins. The electrons at the light bulb end start moving immediately because of the magnetic field and the electrons at the far ends don’t move. Would have been cool to have oscilloscopes at the far ends and somehow sync them all up to show nothing happens at the far ends.
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