The real advancement, not brute forcing mathematical equations like some company does and claims revolutionary breakthrough. How many ideas like this has come from AI companies' models?
This seems to be a known technology but hasn't made it as a product.[1] It might have potential for very specific types of extinguishing, such as grills and grain silos, where the distance from extinguisher to trouble spot is fixed.
Wow, must be the same school that keeps pumping out students who invent water powered cars and machines that turn plastic into gasoline. HN with another YouTube shorts tier front page submission.
"Power a light with a lifted rock": Actually does work and you can buy this product, but it's a dimmer light for less time than the inevitable marketing diagrams indicate. Not useless but the fawning news stories over the science fair prodigy always makes this sound like an unbelievably brilliant solution rather than a rather niche hack even in the poor rural parts of the world. In the 2020s a standard solar panel, battery, and LED light are much better in every way and far more flexible.
"Provide power for a poor rural village from a kicked soccer ball": An absurdly tiny amount of power, at the cost of creating a soccer ball that is soft and doesn't move when you kick it very much, precisely because it's extracting energy from the kick and that energy isn't available to be kinetic energy. No child would ever play with this ball. Have still seen this idea at least three times now despite the fact that if the reporter spent 15 seconds with the actual ball they'd realize it's a complete non-starter.
"Science project demonstrates new way to kill $PATHOGEN": It turns out killing things in a petri dish is really easy. It means nothing about human health outcomes in a body. In fact pretty much anything about a pathogen in a petri dish - improving resistance to something, destroying resistance to something... it's really easy to do lots of things in a petri dish.
"Water from the air": Doesn't work in practice because the place this needs to be deployed to is precisely the place that doesn't have water in the air. It does work in places that have water in the air but those places also don't need super expensive condensed water when they have water already. I personally live in a place where humidity is basically 90-100% every day in spring, summer, and fall. We don't carefully capture our dehumidifier's water.
These are all things I've seen multiple times each.
"No child would ever play with this ball. Have still seen this idea at least three times now despite the fact that if the reporter spent 15 seconds with the actual ball they'd realize it's a complete non-starter."
No child would use it, but those would be really awesome in my Muay-Thai classes.
""Water from the air": Doesn't work in practice because the place this needs to be deployed to is precisely the place that doesn't have water in the air."
There is literally no place on earth where the relative humidity is that low outside the Antarctic dry valleys. Even in the Mojave Desert here, I have a water from air condenser out atop a miner's hotel blasted into rock. I even posted the GPS coordinates to it here on HN. It works great, and produces enough clean water daily for several people. It does need a recharge on the carbonate rock and charcoal, though.
My favorite was the student who demonstrated small, leaf-like solar panels on a tower, and claimed that somehow they were more efficient than a single panel.
No. Not possible. Not even going to do the math. Dumb. Somewhat more wind-resistant... unless you add up the support structure weight AND the loss of efficiency when the "leaves" are wind-deflected.
Well, a search for "youtube acoustic fire extinguisher" indicates it has already been invented a few times by people all over the world. The most interesting video is https://www.youtube.com/watch?v=ZvnCQg4w4o8
Was looking for a video on this specific work, but only found this [1] where the English translation seems AI-generated. It reminded me of thermoacoustic refrigeration which I found cool (heh) when I had encountered it many years ago - where the compression and rarefaction of sound waves is used to pull out heat. The fire extinguisher seems to operate on a different principle though - it needs to generate a specific kind of turbulence to push out oxygen from the fire site.
It's kinda a throw-away remark in the middle, but I thought it was really cool to realize that speakers produce an on-axis net-blow and an off-axis net-suck.
This channel (The Action Lab) is great, it sets an amazingly high standard for clarity of explanation, and for practical combination of experiments and theory, all while being appealing to a broad audience. Most educators would be extremely proud to produce work that's accurate to the standards of a university professor, while remaining appealing to middle-schoolers. I can't imagine what more you want from the content.
he called oxygen the fuel for the fire. the discovery of oxygen was an enormous milestone in the history of science, chemistry, and biology precisely because it's not the fuel for the fire. before that, people knew about fuel, they didn't know about oxygen.
also, he doesn't understand how a bass reflex speaker works. unlike what he said, the port actually decreases the efficiency of the speaker by letting the negative bass note sine waves cancel out the positive sine waves from the front of the speaker, but this is done to tone down the "boominess" of the speaker at its resonant frequency, thus making the speaker more "neutral" sounding, and it's achieved by having the dimensions of the box and the port finely tuned to work most "efficiently" at the resonant frequency.
but in any case, what he says about the "bulk" movement of air (he should probably call it net, i mean all air is bulk by nature) there is no way that the speaker pumping air in and out of the cavity could turn into net movement in one direction. (the smoke ring blower is slowly charged up in one direction, then released in something like an impulse function but loudspeakers don't have that nature) if what he is seeing with his fan-probe is correct, that should have impressed him more and distracted him into studying what exactly was going on (ex: the air coming out was directionally focused from the cone? and sucking back in was amorphous and somehow not detected by his device?) because it is looking for explanation.
tl;dr -- aside from the point about fuel, you mostly don't disagree with him. You have different definitions for the same terms he uses, and you draw your system in a different place than he draws his. Both of you make reasonable choices. A youtube video is not an academic paper, and cannot start by rigorously defining the system under discussion.
> he called oxygen the fuel for the fire... it's not the fuel for the fire
I think you're correct here, from chemistry definitions oxygen is not fuel, because breaking its bond consumes energy rather than releasing it. However, I don't think the host is trying to give perfectly precise chemistry definitions here, he's trying to explain how fire burns, and calling oxygen 'fuel' makes it clear to his audience that oxygen is required for combustion. I think your objection here is similar to objecting that voters in the US elect electors rather than candidates -- it's correct, but not necessary if you're explaining the concept of democracy.
> the port actually decreases the efficiency of the speaker by letting the negative bass note sine waves cancel out the positive sine waves from the front of the speaker, but this is done to tone down the "boominess" of the speaker at its resonant frequency, thus making the speaker more "neutral" sounding
I don't know much about bass reflex speakers, but I read the wikipedia page in decent depth, and it appears to me that you are wrong, or perhaps using a different definition than the field itself uses. From the wiki page: "This port enables the sound from the rear side of the diaphragm to increase the efficiency of the system at low frequencies as compared to a typical sealed- or closed-box loudspeaker or an infinite baffle mounting... Depending on the exact relationship between driver parameters, the enclosure volume (and filling if any), and the tube cross-section and length, the efficiency can be substantially improved over the performance of a similarly sized sealed-box enclosure." [0]. I bet I can see where your disagreement comes from though -- I think you're arguing that adding the reflex speaker cancels some of the power going through the main speaker, and therefore must result in decreased total_power_out/total_power_in (forgive me if I misunderstand). This is a sensible way to define efficiency, and I think you're correct that total_power_out is strictly decreased. However, there are also other sensible ways to define efficiency, eg, instead of total_power_out you might care about the perceptually-weakest frequency the speaker generates, to ensure the sound is "balanced" to a human ear. You might then define efficiency as num_spectral_bins*min_weighted_spectral_power_out/total_power_in. I have some experience optimizing perceived smoothness, and we used a metric very similar to this. Without fully knowing what you mean or what he means, I think you're disagreeing over terms, not correctness.
> but in any case, what he says about the "bulk" movement of air (he should probably call it net, i mean all air is bulk by nature) there is no way that the speaker pumping air in and out of the cavity could turn into net movement in one direction... the air coming out was directionally focused from the cone? and sucking back in was amorphous and somehow not detected by his device?
I think you're agreeing with him here, his explanation matches yours. We can break a full period of oscillation into two sections: a high pressure section (the air molecules being pushed away from the speaker), and a low pressure section (air being pulled back). The high pressure section travels _coherently_ through the air cannon, mostly moving air molecules in a single direction (as you say, it is "directionally focused from the cone"). The low pressure segment pulls air back into the air cannon, but it is _not_ coherent (as you say, it is "amorphous"). During the low section, molecules can flow towards the air cannon from the side of the cannon; they do not have to come from directly in front of the air cannon. If you rewatch that section I think you'll see you're not disagreeing with him. To be fair, more drawings would help communicate it more clearly. You're correct that if you draw your observation box big enough, there can be no net movement from something wiggling back and forth, but I think he's drawing his observation box over the fire. If you look at that system (the air above the fire), you will see net movement.
Watching that dude is like watching a child doing science and then using AI to explain the result. If he makes someone curious enough to do experiments on their own it's still a win though.
It is easy to come away with that idea if you just watch one of his videos. He is very good at clear explanations that get to the essence of an idea and makes it seem simple. Sure, it's at an educational level of detail, but it is accurate on that level.
But if you watch a number of his videos it becomes clear that this is clarity that comes from deep knowledge and sophistication. His channel is also in my opinion notable for having a huge variety of demonstrations, rather than the standard set that is done by a lot of people. There are many things that I've seen only him do, out of my set of science and engineering channels. Which is not to say I know for sure that he is for sure the only one who does them, but it's definitely a more-diverse-than-average set of demonstrations done over the years.
It also, on a more brute level, simply predates AI by a number of years and therefore can't be just an AI script, nor do I see any reason to believe he has switched to using AI to write the scripts.
Prior to “using AI to make videos” he did a phd in chemical engineering. I actually think his explanations and experiments are always very well thought through and presented in a entertaining way
I watch all his videos and they are so easy to understand when to lots of other popular science experiment channels. No high fi stuff, a guy doing experiments with simpler tools available and it's mostly the way he explains things.
Not exactly acoustic but reminds me of a high school science project we had one year, something along the lines of put out a candle with a contraption. My partner and I rigged up a balloon to be popped by the candle, and the balloon pop blows out the candle. Probably not an original idea, but I don't think any other group in the class tried a similar approach. Worked like a charm.
More modern techniques are less violent. I understand one heavily used in Kuwait was to place a ~10 meter hollow pipe above the blown out well so the flame could be displaced from the well head, then injecting water or nitrogen at the base of the pipe to put out the fire.
To clarify, Red Adair and company did take part in the remediation effort in post Gulf War Kuwait:
Many consider his crowning achievement to be his central role in containing the Kuwaiti oil field fires of 1991 that threatened planetary environmental consequences as well as incalculable lost revenues for oil producers. Following a scorched earth retreat policy, Saddam Hussein's defeated army set ablaze more than 700 of Kuwait's 1,000 oil wells. Adair was among the first responders, and his team squelched fires at 117 of the nation's most productive wells.
> Ángela Karime Venegas Hernández is 16 years old and has an idea no one else had.
...meanwhile, some folks at George Mason University were doing this back in 2015[1]:
> The fire extinguisher uses low-frequency sound waves to douse a blaze. Engineering seniors Viet Tran and Seth Robertson now hold a preliminary patent application for their potentially revolutionizing device.
Generally, you get a lot of skepticism when you see an article about high schooler or teenager inventing or discovering something. This is not completely invalid because there have been lots of cases in the past where things like this are just fluff pieces and not actually real breakthroughs, more of a feel good thing. Add onto that that she’s a girl and Mexican and you get even more detractors of the shiftier variety.
I've seen a number of "child invents thing" news stories where the supposed invention was entirely bogus. For example, one widely circulated story in the late 2000s involved a young student in Nepal inventing a solar cell made out of human hair. Their supposed invention made no technical sense, and no one was able to replicate their results.
I sure hope humans are in the loop at those companies, reviewing pics that aren't recognized as faces. If I ever see one of those captchas, they'll get to see some things that no human has ever, or should ever, see.
Love when something decides I'm a bot and the decision is final. (Looking at you, CPU-World -- it even lets me know my IP address has been banned for "abuse", too.)
Stereotyped as less of a STEM country, probably accurately, so it seems newsworthy plus gives people hope and optimism to hear about cool inventions from there.
Haha I loved this: in a thread where everybody is talking about the technology, the merits of the kid "discovering" it and all that, invariably there's the guy who enters the room and shouts "why does people care that she is Mexican!!"
Like... nobody cared, until the guy mentions it. And then he replies back "no I don't care she's Mexican, why do you bring their origin!!!"
FWIW I saw these news in my local news Spanish language sources (yep, Im Mexican too) a couple of days ago. And found the majority of the reporting at that time was exactly a "cool science project" thing.
When I saw it here on HN I was surprised. I even thought like "wow, maybe I didn't put a lot of attention, and it's something bigger". But apparently it's just sloppy reporting, in a telephone-game kind of thing: Some Chilean news saw the headline, and decided to report it as "Mexican 16yo invents X", which draws clicks. Then English based news took it and further deformed the actual facts.
Hopefully this kid gets invited to some podcasts or whatnot and gets something from this. Also hopefully it helps other kids get more interested in sciency projects.
Could you please stop posting unsubstantive comments and flamebait? You've unfortunately been doing it repeatedly. It's not what this site is for, and destroys what it is for.
The average IQ of Koreans is now the highest in the world, after making consistent gains of 8 points per decade for people born between the 1940s and the 1980s. Your ignorance, like IQ, is fixable.
That article has a very silly conclusion with the whole obesity example, and doesn't understand the actual conclusion that the sensitivity analysis that these numbers are derived from, means (especially with their plant example).
Foster families are not that different. I've seen multiple kids raised by parents who value education reading at age 2 and their cousins on either side reading at age 6 because their parents didn't value it. The changes in IQ possible by environmental differences are absolutely massive and clearly far larger than anything genetic aside from severe heritable brain disorders. That's what the Koreans and the Ashkenazim know and exploit. That's what made the large differences between European countries seen in the early 20th century disappear.
The article's obesity conclusion is no less silly than your IQ beliefs.
> Results indicate that genetic influences account for over 60% of the variance in scientific achievement, with environmental influences accounting for the remaining variance.
For a kid, only 40% can be changed.
It's just absolutely wild that people don't think there's a genetic component to intelligence. There are NO studies that suggest otherwise. There's a genetic component to literally every single difference in humans. It's so strange to think that this single dimension is somehow invariant across the genetic populations found across the world.
Can you guess the most reliable way to physically measure someone's intelligence? With our thinking bits being a chunk of meat, it should be fairly obvious!
edit: I can't reply to your opinion, but reference please for this claim "There are small genetic differences in intelligence that are absolutely dwarfed by environmental differences, just like everything else.". Any at all would be fine.
That flies in the face of the evidence. Apply some common sense, and then review the study more carefully. See if you can figure out the methodological failures yourself before you ask me to give you the answer.
There are small genetic differences in intelligence that are absolutely dwarfed by environmental differences, just like everything else. The Koreans weren't genetically engineering themselves to be taller and smarter than their parents and their cousins in DPRK. The Spaniards didn't genetically engineer themselves either.
Edit: Regarding references for my claim, if you don't understand how the example of the Koreans and the Europeans is evidence that environmental factors are more influential than genetic factors, you need a much larger change to your environment to bring your mental abilities up to the task than I can provide.
Please provide some evidence besides your opinion.
> The Koreans weren't genetically engineering themselves to be taller and smarter than their parents and their cousins in DPRK. The Spaniards didn't genetically engineer themselves either.
I don't really understand these genetic engineering points, especially since you use phrasing that includes intent. But, maybe you're saying that height is more related to nutrition than genetics. Yes, but there's a genetic component there as well. A person, feed the same food, will end up at a different height entirely due to genetics.
I can't understand your Spaniards point, but they have a genetic population a bit different than others elsewhere in the world for the same reason as all of them: dicks are only 6 inches long, so geographic isolation results in genetic populations with some level of similarity.
> Please provide some evidence besides your opinion.
I have given you plenty of evidence. See the Koreans, the Spaniards, and the children I described earlier.
> I don't really understand these genetic engineering points
The point is that Korean IQs went up by much more than the gap between Mexicans and Americans, and they didn't have to modify their genetics to do it. Instead, this change was purely environmental.
> I can't understand your Spaniards point
The point is that the gap between Spanish and Scandinavian intelligence was larger than the gap between Mexican and American, and just like for Mexicans, ignorant people complained about Spanish immigration because their faulty reasoning led to attributing the gap to genetics. Now that gap has disappeared. They didn't genetically engineer themselves. This was purely environmental.
> Show me the data
What do you call 8 IQ points per decade if not data?
If she can get it mobile enough , so it can be transported by a drone - it could be forest fire fighting equipment. Bonuspoints if the energy to run it could be derived from the fire itself.
Probably not there's a lot of nearby fire the would reignite extinguished sections because the device doesn't do anything to cool the fuel or suppress fire returning. Also it's short range and very sensitive to the range you use it at.
This technique has been known about since at least 2012 when DARPA did a demonstration of it. There's a reason it hasn't really gone anywhere and mostly exists as science fair demos and Youtube videos now, it's quite limited.
I remember as a kid somewhat accidentally setting a garbage bin on fire before new year's, and successfully putting it out with one of those big cube firecrackers.
At other frequencies, sound can actually intensify flames, depending on the surrounding environment. Standing waves and the frequency of the sound (FM) are likely factors in this phenomenon. However, it’s not advisable to use sound as a method for extinguishing fires.
when i was in the 5th grade (give or take a couple years), there was an innovation project where we were to bring in and present to the class an invention.
i remember a girl inventing what i now know to be a "flexible weighted dip tube" – think of it as a shampoo bottle that you can pump upside down – and was amazed.
like this submission, the flexible straw wasn't really invented by the student. at best it was independently discovered, but this patent was from at least twenty five years before: https://patents.google.com/patent/US3547296A/en
to that end, i wonder what the point of presenting these inventions as your own are – especially in the time of the internet when prior art is so easily discovered. or, did i miss the point?
> i wonder what the point of presenting these inventions as your own are
Because if you independently invented it then it is your own.
The value to the student is not necessarily that the idea is novel to everyone else but that is novel to her. And of course the process of invention and development is something that many people never experience, and is valuable in itself.
I invented a steam engine when I was in 5th grade. It wasn't completely novel nor efficient, but I invented it independently, and my science teacher showed enough interest to spur a 50-year warm memory.
Praising kids for achievements is a net positive. They use it to focus their energy into future growth and development.
The article is science-reporting trash, of course, but praising the kid is a good thing.
They're either dishonest, or they're too stupid to know how to use the internet. You pick. Seriously, what's the alternative here? The only exception would be an honest person too afraid to speak up, to correct the dishonest/incompetent people, and I could agree with that.
I don't blame the kid though. Looks like they did a great job on it!
It's a standard subwoofer speaker/driver put in a ported enclosure, running at 30Hz, creating a particularly "fast punch" sub. The design of this would have all the same goals of a normal subwoofer: moving a bunch of air at low frequency. You can buy this sort of design to listen to music in your car [1]. It all runs on 12 volts because it's standard car audio equipment.
Subwoofers can definitely harm human ears, but definitely not human flesh. Just don't put your ear up to it.
There's plenty of links in Dublin comments for other instances of the tech being developed at least partially, and at least one for in-home fire suppression. Given that last one, I'm thinking it operates on the basis of resonance rather than amplitude to disrupt combustion.
I dont see this working on significant fires. Let it run, separate flame from fuel, but what happens a few seconds later? The fuel is still there, the heat is still there, as soon as the sound stops it will reignite. Water/foam and such create both a physical barrier and immediate cooling to prevent reignition.
As a general rule, cooling any situation involves throwing cold stuff at the hot stuff. We have many means of projecting heat, but no way to project 'cold' without throwing cold stuff.
Water often puts out fires by diluting the oxygen with steam, giving the embers time to cool off.
In practice, the cooling factor is important, but the momentary extinguishment of active flame limits the spread - especially when there is more fuel above.
I'm not saying you're wrong, but what I'm saying is that children deserve a little bit less froth-in-mouth reactions from us adults. Let's be civil, and give praise for curiosity... given that it takes none to be an armchair inventor.
On my read they are criticising the reporter, not the child. We definitely should be careful, in situations like this, not to be nasty to the kids involved. But I think we should still be allowed to be upset by bullshit, and strongly criticize the bullshitters, even when they are bullshitting about a child.
It's shitty reporting. The girl "discovered" the effect by herself, devised a way to use it as a project, and shitty newscasters blew it out of proportion [pun intended]
related to this topic, here is a very interesting little external combustion engine that runs on the heat from a flame directly (i.e. not a steam engine)
The reason this keeps getting reinvented is that the physics only half works. Sound disrupts the flame's boundary layer and separates it from the fuel, but it removes almost no heat. The fuel stays above its ignition temperature, so anything hot nearby relights it the second the speaker stops. DARPA demoed this in 2012 and it stalled there. Impressive on a small liquid fuel fire in a lab, very hard to scale to anything you'd actually want to put out.
Yes, I kind of discovered that in a dream, in which I extinguished a fire by teleporting away oxygen. It worked, until I stopped teleporting. The oxygen came back and the fire started again. When I eventually woke up I thought about it and I told to myself that I should have chilled the place, not that it matters in real life. I was also proud of my subconscious' understanding of physics.
I wonder if one could use a thermal camera (or some other, high speed sensor) and some kind of feedback loop to squelch it and keep it disrupted until it cools. Or conversely, manipulate the flame for more complete combustion (in industrial processes).
But granted, I have trouble seeing this work on a large scale without much more sophisticated sonic wave tech.
Same application spectrum as CO2 fire extinguishers I'd imagine (which we use for expensive lab hardware that we don't want to get damaged by water, foam, ..., but which are utterly useless for anything more substantial becuase it just reignites).
Sure, but this "invention" isn't new. It seems to make the internet rounds every few months. Here's one from 11 years ago that looks almost identical: https://www.youtube.com/watch?v=uPVQMZ4ikvM - I wonder how their "preliminary patent application" went...
Just simply: it is great that young people, driven by personal curiosity, go and explore their ideas, find solutions to long-standing challenges.
Billiant, keep inventing!
[1] https://www.mdpi.com/2571-6255/8/4/129
"Power a light with a lifted rock": Actually does work and you can buy this product, but it's a dimmer light for less time than the inevitable marketing diagrams indicate. Not useless but the fawning news stories over the science fair prodigy always makes this sound like an unbelievably brilliant solution rather than a rather niche hack even in the poor rural parts of the world. In the 2020s a standard solar panel, battery, and LED light are much better in every way and far more flexible.
"Provide power for a poor rural village from a kicked soccer ball": An absurdly tiny amount of power, at the cost of creating a soccer ball that is soft and doesn't move when you kick it very much, precisely because it's extracting energy from the kick and that energy isn't available to be kinetic energy. No child would ever play with this ball. Have still seen this idea at least three times now despite the fact that if the reporter spent 15 seconds with the actual ball they'd realize it's a complete non-starter.
"Science project demonstrates new way to kill $PATHOGEN": It turns out killing things in a petri dish is really easy. It means nothing about human health outcomes in a body. In fact pretty much anything about a pathogen in a petri dish - improving resistance to something, destroying resistance to something... it's really easy to do lots of things in a petri dish.
"Water from the air": Doesn't work in practice because the place this needs to be deployed to is precisely the place that doesn't have water in the air. It does work in places that have water in the air but those places also don't need super expensive condensed water when they have water already. I personally live in a place where humidity is basically 90-100% every day in spring, summer, and fall. We don't carefully capture our dehumidifier's water.
These are all things I've seen multiple times each.
https://xkcd.com/1217/
No child would use it, but those would be really awesome in my Muay-Thai classes.
""Water from the air": Doesn't work in practice because the place this needs to be deployed to is precisely the place that doesn't have water in the air."
There is literally no place on earth where the relative humidity is that low outside the Antarctic dry valleys. Even in the Mojave Desert here, I have a water from air condenser out atop a miner's hotel blasted into rock. I even posted the GPS coordinates to it here on HN. It works great, and produces enough clean water daily for several people. It does need a recharge on the carbonate rock and charcoal, though.
No. Not possible. Not even going to do the math. Dumb. Somewhat more wind-resistant... unless you add up the support structure weight AND the loss of efficiency when the "leaves" are wind-deflected.
But "Green!", so it got attention.
[1] https://www.youtube.com/watch?v=TGO7Jdfll7c
[2] https://en.wikipedia.org/wiki/Thermoacoustic_heat_engine
also, he doesn't understand how a bass reflex speaker works. unlike what he said, the port actually decreases the efficiency of the speaker by letting the negative bass note sine waves cancel out the positive sine waves from the front of the speaker, but this is done to tone down the "boominess" of the speaker at its resonant frequency, thus making the speaker more "neutral" sounding, and it's achieved by having the dimensions of the box and the port finely tuned to work most "efficiently" at the resonant frequency.
but in any case, what he says about the "bulk" movement of air (he should probably call it net, i mean all air is bulk by nature) there is no way that the speaker pumping air in and out of the cavity could turn into net movement in one direction. (the smoke ring blower is slowly charged up in one direction, then released in something like an impulse function but loudspeakers don't have that nature) if what he is seeing with his fan-probe is correct, that should have impressed him more and distracted him into studying what exactly was going on (ex: the air coming out was directionally focused from the cone? and sucking back in was amorphous and somehow not detected by his device?) because it is looking for explanation.
> he called oxygen the fuel for the fire... it's not the fuel for the fire
I think you're correct here, from chemistry definitions oxygen is not fuel, because breaking its bond consumes energy rather than releasing it. However, I don't think the host is trying to give perfectly precise chemistry definitions here, he's trying to explain how fire burns, and calling oxygen 'fuel' makes it clear to his audience that oxygen is required for combustion. I think your objection here is similar to objecting that voters in the US elect electors rather than candidates -- it's correct, but not necessary if you're explaining the concept of democracy.
> the port actually decreases the efficiency of the speaker by letting the negative bass note sine waves cancel out the positive sine waves from the front of the speaker, but this is done to tone down the "boominess" of the speaker at its resonant frequency, thus making the speaker more "neutral" sounding
I don't know much about bass reflex speakers, but I read the wikipedia page in decent depth, and it appears to me that you are wrong, or perhaps using a different definition than the field itself uses. From the wiki page: "This port enables the sound from the rear side of the diaphragm to increase the efficiency of the system at low frequencies as compared to a typical sealed- or closed-box loudspeaker or an infinite baffle mounting... Depending on the exact relationship between driver parameters, the enclosure volume (and filling if any), and the tube cross-section and length, the efficiency can be substantially improved over the performance of a similarly sized sealed-box enclosure." [0]. I bet I can see where your disagreement comes from though -- I think you're arguing that adding the reflex speaker cancels some of the power going through the main speaker, and therefore must result in decreased total_power_out/total_power_in (forgive me if I misunderstand). This is a sensible way to define efficiency, and I think you're correct that total_power_out is strictly decreased. However, there are also other sensible ways to define efficiency, eg, instead of total_power_out you might care about the perceptually-weakest frequency the speaker generates, to ensure the sound is "balanced" to a human ear. You might then define efficiency as num_spectral_bins*min_weighted_spectral_power_out/total_power_in. I have some experience optimizing perceived smoothness, and we used a metric very similar to this. Without fully knowing what you mean or what he means, I think you're disagreeing over terms, not correctness.
> but in any case, what he says about the "bulk" movement of air (he should probably call it net, i mean all air is bulk by nature) there is no way that the speaker pumping air in and out of the cavity could turn into net movement in one direction... the air coming out was directionally focused from the cone? and sucking back in was amorphous and somehow not detected by his device?
I think you're agreeing with him here, his explanation matches yours. We can break a full period of oscillation into two sections: a high pressure section (the air molecules being pushed away from the speaker), and a low pressure section (air being pulled back). The high pressure section travels _coherently_ through the air cannon, mostly moving air molecules in a single direction (as you say, it is "directionally focused from the cone"). The low pressure segment pulls air back into the air cannon, but it is _not_ coherent (as you say, it is "amorphous"). During the low section, molecules can flow towards the air cannon from the side of the cannon; they do not have to come from directly in front of the air cannon. If you rewatch that section I think you'll see you're not disagreeing with him. To be fair, more drawings would help communicate it more clearly. You're correct that if you draw your observation box big enough, there can be no net movement from something wiggling back and forth, but I think he's drawing his observation box over the fire. If you look at that system (the air above the fire), you will see net movement.
[0] https://en.wikipedia.org/wiki/Bass_reflex
But if you watch a number of his videos it becomes clear that this is clarity that comes from deep knowledge and sophistication. His channel is also in my opinion notable for having a huge variety of demonstrations, rather than the standard set that is done by a lot of people. There are many things that I've seen only him do, out of my set of science and engineering channels. Which is not to say I know for sure that he is for sure the only one who does them, but it's definitely a more-diverse-than-average set of demonstrations done over the years.
It also, on a more brute level, simply predates AI by a number of years and therefore can't be just an AI script, nor do I see any reason to believe he has switched to using AI to write the scripts.
https://www.infobae.com/mexico/2026/08/27/se-puede-apagar-el...
[0] https://www.reddit.com/r/physicsgifs/comments/5omaxc/oil_wel...
...meanwhile, some folks at George Mason University were doing this back in 2015[1]:
> The fire extinguisher uses low-frequency sound waves to douse a blaze. Engineering seniors Viet Tran and Seth Robertson now hold a preliminary patent application for their potentially revolutionizing device.
[]: https://patents.google.com/patent/US10569115B2/en
[1]: https://www.youtube.com/watch?v=uPVQMZ4ikvM
That said, it's a solid student project. I'm sure she'll do well at university.
[1]: https://www.ifsecglobal.com/uncategorized/soundwaves-a-new-p...
[2]: https://www.esd.whs.mil/Portals/54/Documents/FOID/Reading%20...
https://phdcomics.com/comics/archive.php?comicid=1174
> Verify you are human
Does anyone else command + w on first sight of a cloudflare screen?
https://www.tomshardware.com/tech-industry/googles-camera-ba...
Like... nobody cared, until the guy mentions it. And then he replies back "no I don't care she's Mexican, why do you bring their origin!!!"
FWIW I saw these news in my local news Spanish language sources (yep, Im Mexican too) a couple of days ago. And found the majority of the reporting at that time was exactly a "cool science project" thing.
When I saw it here on HN I was surprised. I even thought like "wow, maybe I didn't put a lot of attention, and it's something bigger". But apparently it's just sloppy reporting, in a telephone-game kind of thing: Some Chilean news saw the headline, and decided to report it as "Mexican 16yo invents X", which draws clicks. Then English based news took it and further deformed the actual facts.
Hopefully this kid gets invited to some podcasts or whatnot and gets something from this. Also hopefully it helps other kids get more interested in sciency projects.
I wasn't implying anything, just wondering why it needs to be in the title.
If you wouldn't mind reviewing https://news.ycombinator.com/newsguidelines.html and taking the intended spirit of the site more to heart, we'd be grateful.
[1] https://worldpopulationreview.com/state-rankings/average-iq-...
The average IQ of Koreans is now the highest in the world, after making consistent gains of 8 points per decade for people born between the 1940s and the 1980s. Your ignorance, like IQ, is fixable.
The article's obesity conclusion is no less silly than your IQ beliefs.
> Results indicate that genetic influences account for over 60% of the variance in scientific achievement, with environmental influences accounting for the remaining variance.
For a kid, only 40% can be changed.
It's just absolutely wild that people don't think there's a genetic component to intelligence. There are NO studies that suggest otherwise. There's a genetic component to literally every single difference in humans. It's so strange to think that this single dimension is somehow invariant across the genetic populations found across the world.
Can you guess the most reliable way to physically measure someone's intelligence? With our thinking bits being a chunk of meat, it should be fairly obvious!
edit: I can't reply to your opinion, but reference please for this claim "There are small genetic differences in intelligence that are absolutely dwarfed by environmental differences, just like everything else.". Any at all would be fine.
There are small genetic differences in intelligence that are absolutely dwarfed by environmental differences, just like everything else. The Koreans weren't genetically engineering themselves to be taller and smarter than their parents and their cousins in DPRK. The Spaniards didn't genetically engineer themselves either.
Edit: Regarding references for my claim, if you don't understand how the example of the Koreans and the Europeans is evidence that environmental factors are more influential than genetic factors, you need a much larger change to your environment to bring your mental abilities up to the task than I can provide.
Please provide some evidence besides your opinion.
> The Koreans weren't genetically engineering themselves to be taller and smarter than their parents and their cousins in DPRK. The Spaniards didn't genetically engineer themselves either.
I don't really understand these genetic engineering points, especially since you use phrasing that includes intent. But, maybe you're saying that height is more related to nutrition than genetics. Yes, but there's a genetic component there as well. A person, feed the same food, will end up at a different height entirely due to genetics.
I can't understand your Spaniards point, but they have a genetic population a bit different than others elsewhere in the world for the same reason as all of them: dicks are only 6 inches long, so geographic isolation results in genetic populations with some level of similarity.
Show me the data.
I have given you plenty of evidence. See the Koreans, the Spaniards, and the children I described earlier.
> I don't really understand these genetic engineering points
The point is that Korean IQs went up by much more than the gap between Mexicans and Americans, and they didn't have to modify their genetics to do it. Instead, this change was purely environmental.
> I can't understand your Spaniards point
The point is that the gap between Spanish and Scandinavian intelligence was larger than the gap between Mexican and American, and just like for Mexicans, ignorant people complained about Spanish immigration because their faulty reasoning led to attributing the gap to genetics. Now that gap has disappeared. They didn't genetically engineer themselves. This was purely environmental.
> Show me the data
What do you call 8 IQ points per decade if not data?
This technique has been known about since at least 2012 when DARPA did a demonstration of it. There's a reason it hasn't really gone anywhere and mostly exists as science fair demos and Youtube videos now, it's quite limited.
https://www.xprize.org/competitions/wildfire
Is that really what happens? Wouldn't the fire be surrounded by the same air?
No, I dont think I will. closes website
Cloudflare at the forefront of gatekeeping everything on the website
i remember a girl inventing what i now know to be a "flexible weighted dip tube" – think of it as a shampoo bottle that you can pump upside down – and was amazed.
like this submission, the flexible straw wasn't really invented by the student. at best it was independently discovered, but this patent was from at least twenty five years before: https://patents.google.com/patent/US3547296A/en
to that end, i wonder what the point of presenting these inventions as your own are – especially in the time of the internet when prior art is so easily discovered. or, did i miss the point?
Because if you independently invented it then it is your own.
The value to the student is not necessarily that the idea is novel to everyone else but that is novel to her. And of course the process of invention and development is something that many people never experience, and is valuable in itself.
Praising kids for achievements is a net positive. They use it to focus their energy into future growth and development.
The article is science-reporting trash, of course, but praising the kid is a good thing.
Regardless, nobody involved is honest, and I suspect the honest ones were told the be quiet.
I don't blame the kid though. Looks like they did a great job on it!
Subwoofers can definitely harm human ears, but definitely not human flesh. Just don't put your ear up to it.
[1] https://cadencesound.com/product/tube12vp/?srsltid=AfmBOoqdE...
Depending on what they have going, it might be loud, might not.
Hate to be a downer, but this has been done before.
https://acoustics.org/pressroom/httpdocs/150th/Plaks.html
As a general rule, cooling any situation involves throwing cold stuff at the hot stuff. We have many means of projecting heat, but no way to project 'cold' without throwing cold stuff.
In practice, the cooling factor is important, but the momentary extinguishment of active flame limits the spread - especially when there is more fuel above.
As others have mentioned it's not the first time.
So, is the reporter willfully lying, or is so incompetent that couldn't even do a simple Google search? I don't know which is worse.
https://i.4cdn.org/b/1789145070031855.mp4 (completely SFW)
(links to 4chan expire in a day or so, so if anybody has a better link for this, future generations will be able to see it too)
DARPA worked on it 10+ years ago.
But granted, I have trouble seeing this work on a large scale without much more sophisticated sonic wave tech.