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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]

#131

Post by function_seven »

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.

Parent's use of "instantly" is a bit imprecise. Here "instantly" means after 1 ns, whereas "speed of light delay" means the delay over the full 500m distance out and back.

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

#132

Post by Lerc »

BenFrantzDale wrote: post #114
negative_zero wrote: post #101

Earlier quoted context omitted.

I think the controversy is because that while being technically correct (bar a couple of mistakes) there are two main issues: 1) To get the result presented heavily depends on the experimental setup and this appears to be hand-waved away (or for the cynics: deliberately obscured) as it would detract from the impact of the video. 2) The definition of "ON" in the video is not what anybody would reasonably define as "ON…

His technical errors include the “correct” multiple-choice answer being that the time to turn on is “1/c s”. That evaluates to 3.3e-9 s^2/m. It’s not even a time. Failing basic dimensional analysis is grossly sloppy.

The correct units would have tipped his hand and led people to realize the 1m separation of the wires is relevant and thus people would reconsider antenna approaches. That would blunt the gotcha effect.

That's not sloppy, it's disingenuous.

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

#133

Post by dylan604 »

Jansen312 wrote: post #99
TempestSA wrote: post #35

Why wouldn't a simpler explanation be that the wires produce a radio/electromagnetic wave and that wave gets picked up and induces a current, which is how radio transmitters receivers work?

Most people didn't have EE education at college level. Transmission line or radio wave carrying energy is a concept usually taught much later in ones schooling. Derek basically want to target mass market that receive basic electrical knowledge that actively tells you electric "only" flows in cable. A lot of people replying to his video subsequently demonstrate that Derek is right that these group of people have the n…

>people have the not exactly right idea taught at school

could it not also be that some of these students didn't actually learn what was being taught, and just squeaked by with minimum grades to not have to take it again?

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

#134

Post by ehsankia »

allemagne wrote: post #80
tpush wrote: post #76

So, I genuinely do not get the "controversy" over the Veritasium video. AFAIU, the entire point of the video was to show that electricity travels not through wires but via electric fields ("through the air" so to speak). To illustrate this, he sets up an experiment with parameters such that the conclusion can only mean that some electricity has traveled to the bulb before any could arrive through/around the wires. He…

I would echo this sentiment. Did this video not confirm exactly what Veritasium claimed (the small but noticeable "instantaneous" i.e. 1/c current)?

I think the confusion is that Veratisium's original video made it seem like this was the only/main way electricity travels, whereas in reality, there's two separate ways: One of them take's 1/c and the other takes c/2. Also, what most people think of the light bulb going on in the real world would be the c/2 one, not the 1/c one.

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

#135

Post by ehsankia »

zokier wrote: post #40

The thing that is most curious in this tempest in a teacup is why didn't Veritasium film this experiment themselves. It isn't particularly complicated or expensive setup, so it seems something that he definitely could have done. Instead he chose to leave the door open for the controversy that followed.

I was surprised by that too, though it seems like he is actually working on such a video now. Honestly I have a feeling that this kind of science debate style content is becoming more popular. There was the Veritasium vs physic teacher about the faster-than-wind car, and also the Steve Mould vs ElectroBOOM about Mould Effect recently. Maybe he intentionally left it vague to get people to debate with him.

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

#136

Post by phendrenad2 »

lamontcg wrote: post #130
gcommer wrote: post #96

Earlier quoted context omitted.

There's two bits of controversy: 1) Slander: He claims that the way EE is taught is a "lie" but leaves out the many ways that standard EE models agree with his result. 2) Clickbait / inadequate explanation: he leaves out many details in order to make his experiment seem far more mind-blowing that it really is.* Critique 1 can be countered by saying he is targeting a lay audience (say, they took 1 high school physics…

The problem is that his video is a mish-mash of two different concepts that were taught perfectly well in my freshman physics course. One is that the electric field travels down a wire at the speed of light while the electrons do not. The other is induced currents by moving charges. I got the answer "wrong" by watching the video because I didn't consider the tiny amount of current induced in the other wire to be suff…

This is exactly it. If being "right" or "wrong" about something involves subjective facts (is the lamp "lit" by the small amount of electricity induced by cosmic rays too?!?!) and trying to visually inspect an experiment you can't access in-person, then the only thing "wrong" is the video maker.

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

#137

Post by shukantpal »

BenFrantzDale wrote: post #114
negative_zero wrote: post #101

Earlier quoted context omitted.

I think the controversy is because that while being technically correct (bar a couple of mistakes) there are two main issues: 1) To get the result presented heavily depends on the experimental setup and this appears to be hand-waved away (or for the cynics: deliberately obscured) as it would detract from the impact of the video. 2) The definition of "ON" in the video is not what anybody would reasonably define as "ON…

His technical errors include the “correct” multiple-choice answer being that the time to turn on is “1/c s”. That evaluates to 3.3e-9 s^2/m. It’s not even a time. Failing basic dimensional analysis is grossly sloppy.

It should be obvious that the "c" here was used as a magnitude not with units. Saying that's "failing dimensional analysis" is in itself grossly sloppy - since it totally misses the context.

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

#138

Post by blondin »

Jansen312 wrote: post #88
formerly_proven wrote: post #37

Earlier quoted context omitted.

I'm not an avid Veritasium viewer but from what I've seen this MO seems to be kinda his shtick.

Veritasium is the better teacher. The rest is just jumping on the bandwagon to grab viewerships. Think about it, back in your school days, you have an inspirational teacher that challenge or motivate you to pursue something. Rarely that teacher will spoonfed you with all information. I have many great teachers that explain well. But not a single one of them make it to the list of inspirational. I have 1-2 memorable t…

sorry, veritasium is not / no longer the channel you think it is.

they are not out to teach first.

teaching became second at some point. making views became first and more important. it is totally understandable. (they talk about the team, paying people, etc.) i personally appreciate the honesty. the video they did around the subject should still be around.

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

#139

Post by notfed »

allemagne wrote: post #80
tpush wrote: post #76

So, I genuinely do not get the "controversy" over the Veritasium video. AFAIU, the entire point of the video was to show that electricity travels not through wires but via electric fields ("through the air" so to speak). To illustrate this, he sets up an experiment with parameters such that the conclusion can only mean that some electricity has traveled to the bulb before any could arrive through/around the wires. He…

I would echo this sentiment. Did this video not confirm exactly what Veritasium claimed (the small but noticeable "instantaneous" i.e. 1/c current)?

The controversy is that it twists the standard definition of "on": the video boldly asserts its shocking answer of 1/d at first, only later to admit (with very little clarity) that the 1/d answer is only true if your definition of "on" is a small electromagnetic spike.

This also means that the "misconception" claim is really just click-bait and really there was never any misconception.

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

#140

Post by [deleted] »

stormbrew wrote: post #62
paxys wrote: post #11

Earlier quoted context omitted.

That video perfectly summarizes online discourse. I personally found it fantastic as a resource. It was the best and most clear explanation of transmission of energy in an electrical circuit that I have seen. It debunked a lot of myths in my head that we were all taught in school. The thought experiment he proposed was just a hook to keep people interested - and it certainly did the job. Because it is a popular inter…

I'm sorry but no, the original video does clarify some important things that people misunderstand about transmission of electricity, but then it piles on a bunch of other really unclear information with no explanation. It answers a question with about 8 other questions and then offers no help in understanding any of them. You can't just say "there's electricity at the light bulb nearly immediately! (oh by the way it'…

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