Risking My Life To Settle A Physics Debate

[@veritasium]

If you want more detail on the explanation here it is: 1. The car is powered only by the wind. There is no motor or batteries of any kind. 2. The propeller does NOT spin like a windmill. The wind does NOT push it and make it turn. 3. Instead the wheels are geared to the propeller to turn it the opposite way, like a fan, so it pushes air backwards. 4. To start the vehicle the wind simply pushes on the whole vehicle (like a block of styrofoam) and gets it moving. 5. The wheels are turning so they turn the propeller in the opposite direction to how the wind is pushing it. 6. The prop is pushing air back so air pushes the prop forwards, accelerating the car. 7. Once you get up to wind speed there is no apparent wind on the vehicle. If the prop were spun like a windmill this would mean no more thrust. But, since the prop is operating like a fan, it still accelerates air backwards, generating thrust. 8. You can go faster than wind speed continuously because even when going faster than the wind, the prop can still accelerate air backwards (in the car's frame of reference) generating thrust. In a stationary frame of reference you would see that the wind behind the propellor is slower than the surrounding air. So it's clear that the energy is coming from the wind. FAQ: If power is coming from the wheels to turn the prop, why doesn't that slow down the wheels more than it gets the prop to push back? A: Because the wheels are moving over the ground much faster than the prop is moving through the air (because there's a tailwind). Example: Let's say the car is going 12m/s in a 10m/s tailwind, so faster than the wind (note the prop will be moving through an apparent headwind of 2m/s). Power = Force x Velocity Let's say the chain applies a drag force of 100N on the wheels to drive the prop. This means we're taking power from the wheels = FxV = 100N x 12m/s = 1200W If we apply this power to the fan, it can create a force of F = P/V = 1200W / 2m/s = 600N Admittedly I've assumed no losses, but even if we waste half the power, we'd still get 300N of thrust which is more than the 100N of drag the prop adds to the wheels. The key is that we're harvesting power at higher speed, lower force, and deploying it at lower speed, higher force (which is only possible because we have a tailwind - in still air this wouldn't work because the relative velocity of the wheels over the ground would be exactly the same as the relative velocity of the prop through the air).

[@johnborton4522]

Nicely done Derek (from the co-designer/builder of the Blackbird)

[@greenkid336600]

There appeared to be gears for shifting. Is there an optimal reduction/force conversion?

[@coolaun]

Good explanations. Just one niggle: in point 4 you say "To start the vehicle the wind simply pushes on the whole vehicle". In fact even at the start, with the vehicle stationary on the ground, the forward force of the air on the prop is greater than the backward force of the ground on the wheels, due to the gearing ratio. So there's no need for "bluff body" to self start.

[@FURY-bc6cj]

Love from India

[@SLA-yo4is]

It was cool!

[@PotatoJet]

Sending this video to my mom! She’ll be so proud of me..... for once.....

[@Philitron128]

Great work on the video man!

[@edwardneal4819]

Yeah. But I'm sure she'll still love you just the same. LOL!

[@gantekkrystal5102]

"Potato Mom here, proud of you son. Now, When will you get a real job?" /s

[@ballmantalk]

Asian problems I guess

[@Rick_Cavallaro]

Your mother and I have always been proud of you!

[@Tluangtea]

When your online argument with random people is so heated you ended up building a vehicle that seems to defy logic....

[@JimmyJonJillakers]

Just a few steps above "I am trained in gorilla warfare"

[@finlaymcdiarmid5832]

Was the guy who made it from florida?

[@nervousstate]

Just another day on Reddit

[@The_Viktor_Reznov]

"Source: dude, trust me" took personally

[@Fyr35555]

It's like a more sane version of the flat earther who built his own rocket (and ended up killing himself) and with actual scientific basis of course

[@flatfourtwenty]

The inventor must have been grinning so hard in that shot where he's holding the wind sock. Basically got the best shot possible with great equipment that he was right all along.

[@Fs3i]

And distributed to a large audience, with a non-neglible part being scientifically literate.

[@ericeaton2386]

If you look closely in the slo-mo shot, you can see that in fact, he has a huge grin, haha.

[@villz1267]

Literal picture perfect slowmo windsock vs telltale

[@Fortzon]

"That'll finally show them internet trolls and professors!"

[@crazymotionride]

Lord Brabazon is the inventor of the auto gyro rig. He had a boat with one on in 1934 and proved this worked back then.

[@albertorip]

As a windsurfer already going (much) faster than wind while sailing sidewind seems magic, but the physic involved it's not so difficult in the end: just some vectors. The very brilliant thing here is to have made a device that can go "sidewind" while going downwind.

[@narrenmagie]

I have watched 3 videos about this phenomenon now trying to understand the underlying principle / the idea behind it. I didn't really get it. You put it into two beautiful sentences and I realized what's going on. Great! Thanks!

[@FDUflyingrobin]

@@narrenmagie That's the spiral cartoon at the beginning of the video. It showed it quite clearly but it didn't verbally explain it explicitly.

[@ОлександрХірх-Ялан]

Windsurfer can go faster than wind but not in wind direction. If you starts going down too much - you lost your power and sail stops to pull you futher. thats why maximum speead are reached at 120dergre from wind, but not 180.

[@sailbatten2056]

@@ОлександрХірх-Ялан To be clear, this is what the OP was saying; it's not in opposition to it.

[@Nikarus2370]

Even though I know it works and have sailed a small bermuda rigged boat into the wind faster than the wind blowing the other way... still makes my head hurt thinking about wy it works.

[@COTU9]

It's not breaking the laws of physics, it's breaking the laws of understanding.

[@emostorm7]

Yes

[@elevenpsy]

To the ignorant. Otherwise it's just intriguing.

[@AndrewThibeault]

Yes, this. If it looks like it breaks the laws of physics, then we don't understand that particular part of physics enough.

[@gordoncellist]

This!

[@darkcognitive]

Preach.

[@skaruts]

lol true inventor spirit: _"how do I stop this?"_ _"you, uuh... I dunno, push the lever."_ _"which lever?"_ _"the one that stops it!"_

[@fredfrancium]

If he turns on the opposite side of the wind, then it should stop. But he has short time to jump out before it start again 😬😬

[@DEV-rw7eu]

Ah yes the floor is made out of floor

[@zemsaney433]

It's the equivalent of gow4 when kratos says Kratos: find deer Atreus: where? kratos: in the direction of deer

[@killerhawks]

Krunk push the lever.... WRONG LEVER....LOL

[@zemsaney433]

@@CreativityForever I probably used sub bots and that's literally a fake verification mark next to your name

[@parjitkhakh6970]

"If I put two sailboats, that's a prop" that explanation was mind-blowing.

[@KanuckStreams]

It was at that moment that I understood his logic.

[@lordquintus1419]

Yeah that is by far my favorite explanation for propellers ever

[@metamorphicorder]

Well its a rough clumsy metaphor. In the two sailboat model, theres no direct communication or action reaction between them. A less visually stunning explanation is that the prop acts as a sail, although in this case, an active sail rather than a reactive one, and that its spinning is exxientially the equivalent of tacking a boat into the wind. Instead of changing the direction of the vehicle as a whole it channels that energy into an axel around whice spins the prop. The prop, you cant think of it as a reverse sail, grabs air and changes its direction and velocity, gaining some in the process. The change in direction of a boat tacking is now the rotation of the prop.

[@mathiasvofrey9240]

only that this analogy Cannot apply because it requires the boat(s) to Not move in the same speed and direction as the wind itself which the wheeled vehicle is doing. please forget all about the boats, they should never have mentioned the boats. just think about the model on the treadmill, specifically on startup, imagine you are only holding/pushing the model with a finger (reallife wind is your finger) then see what happens...

[@decidrophob]

For me, sailboats traveling faster than the wind is way more counterintuitive than the propellers absorbing wind energy that Derek explained towards the end of the video. Do you guys understand how sailboats go fast without understanding Navier-Stokes equation or some equivalent sophisticated fluid dynamics?

[@willh1655]

I was blown away that so many physicists called it fake or impossible.

[@decone4839]

you were blown away

[@SavingMsBlack]

Don’t be. - Copernicus

[@Kirkaig]

same

[@TheRodmena]

The reason I left university.

[@Anialatedable]

​@@TheRodmena A flunky who uses any excuse to make themself feel better. Lol. People disagreeing and attempting to disprove each other is how Science happens. Else we get people who believe in bs without questioning it.

[@TimeBucks]

the two boats on a cylinder acting like a propeller! That's amazing

[@dinosaur8150]

Right!

[@Super.AmmarI0]

5 feet apart

[@AMIRULHAQE]

yes that was incredible

[@rtmordecai1]

Physicist: How do I figure out how this works? Oh right what if the earth were a cylinder? Us: wtf?

[@Abdullah-yq7jp]

New plots/mechanism for sci-fi Wish I was creative enough for it though

[@T33K3SS3LCH3N]

Damn the explanation with the two sailboats was amazing.

[@terbo2000]

I agree that's when it clicked for me. Once we imagine the boats spiraling around the cylindrical earth, we can lock the boats in place and now the earth is spinning. Congratulations! You've made a torque!

[@yayayayya4731]

@@terbo2000 it was like that moment when you realise 💡

[@blakereid5785]

It was kinda sneaky, in a good way. Oops high jacked your brain.

[@fatsquirrel75]

I still don't understand how boats travel faster than the wind. But knowing they can made that explanation a winner.

[@jmacd8817]

No. That explanation is 2 separate vehicles tacking. The geometry looks the same, but the physics is wrong. Using the wind to blow the body of the vehicle, and the prop pushing, works fine

[@nicholasstathopoulos4731]

"That's great in practice, but how does it work in theory?"

[@dougearnest7590]

This will be the most brilliant comment of them all.

[@haraldschurr1035]

great comment!

[@bobbilaval6171]

You win the Internet today

[@cragnog]

bark bark!

[@jackgilmore152]

Elite comment my friend bravo

[@PIXXO3D]

Now just give it a few years and we will have the first-ever cylinder earthers.

[@Thomas_York]

Please no, the flat earthers are enough 😭

[@victorsago]

@@Thomas_York Yeah, they're a lot of fun! :P Now, imagine them arguing with the cylinder earthers! 😂

[@gadiantonx8474]

a few more years with the huge mining equipment and it might take a cylindrical shape

[@HelloThere.....]

Actually, that already exists. Some believe earth is a 4th dimensional cylinder and that's why we can circumnavigate it. Funnily enough, it's true to some extend, but that very fact would actually cause the earth to be round because a curve in time would automatically cause gravity and make the earth round. I mean think about it, if the earth was curved in spacetime, and all information that travelled around this curve would also experience an altered path in 3 dimensions, then what you'd have is a sphere because the earth itself would also move according to its 4th dimensional curve, as the outer edges travel along the longer curve, the inner edges would travel along the shorter path and take less time to do so, you'd then get an inverse square law of strength of curvature induced change in motion starting from the center of the earth which would make it round. It also would mean the ground is accelerating upward, as the earth rotates and travels along the curved spacetime. Even more ironically, many flat earthers believe gravity is just the result of the ground accelerating up. They think that disproves gravity but it actually proves it because that's literally what happens due to gravity.

[@_TheCollective]

Jokes on you the earth is dinosaur nugget shapex

[@timkimmel9935]

"JUST GO WITH WHAT FEELS LIKE IS SLOWING YOU DOWN" SCIENCE!!!!!!!!

[@vaisakh_km]

This deserves more like...

[@sabarisuresh1458]

physics!!!

[@thombruce]

Science isn't an exact science.

[@frankharr9466]

Better. It's engineering. Prototype engineering.

[@dargtagnan3696]

*engineering

[@danyalag3366]

That shot when the man is standing clearly showing the wind s blowing opposite to what the piece of string is showing on the blackbird is ICONIC!

[@GregHassler]

16:31

[@DonVigaDeFierro]

That's one for the books.

[@DaFlameGamers]

@@GregHassler 16:28

[@Rishi_CA]

16:21 the tail moves backwards ☝🏼

[@initialb123]

Hope there was a nice shot of it from a camera guy in teh follow car , so he can get it framed

[@alecmalisheski36]

Experiments made out of spite to prove people wrong is the best kind of science

[@ozhinz]

correct

[@yes-tk2rr]

correct

[@VENOgrad]

correct

[@elkinmontoya9640]

correct

[@keyboardwarrior4994]

I think the initial concept was not to prove people wrong. The initial one was purely to come up with a vehicle design which will take it faster than the wind. However, as always in scientific research, there will be critiques, negative reviews, etc. That's what you see as "out of spite to prove people wrong". No, it's not out of spite to prove people wrong. It's part of their research to prove that their design works. Anyways, their research does have promising future. It might add and build a foundation for further development on non-fossil fuel wind-powered transport vehicles. Going faster than the wind is a big deal.

[@eldyy9328]

The best part is even when they had a working model people on the internet told them it was impossible. If you have an idea you think will work don't let the internet stop you.

[@youngisaiah3499]

stan lee quote

[@Frankovelli]

The reasoning that propelled him to make a working model was the same reasoning that was preventing people from accepting it as true. If it didn't need to be seen to be believed, people would have just taken their word for it.

[@HealthCarePro]

They say perpetual motion is impossible, but then, right from electrons to planets and stars and galaxies, everything is in motion...perpetually. We need to change how we look at things.

[@EricPalmer_DaddyOh]

There is a lot of stuff on the internet that is faked. I trust Derek. He has a reputation for an Element of Truth.

[@191246mann1]

he didn't make working model ,,,@@Frankovelli

[@checkboxxxproductions]

Here´s a civil comment: This is scientifically possible. There are no laws broken here. Keep up the good work!

[@johanmedrano1924]

Here's an uncivil comment: Goku would beat him.

[@checkboxxxproductions]

@@johanmedrano1924 loooooool

[@thedude6058]

@@johanmedrano1924 x to doubt

[@johanmedrano1924]

@@thedude6058 dude, dont get me started 😂😂😂

[@thanosmom9118]

@@johanmedrano1924 Saitama is way stronger than Goku.

[@an_annoying_cat]

"I am not a stupid person, but i cannot understand" is now my new favorite quote

[@apeanders]

Turns out, the two are not mutually exclusive.

[@DoctorMagoo111]

That was my favorite of the forum comments. No blowharding or trying to disprove things, just an earnest acknowledgment of not understanding.

[@n0us.]

@@DoctorMagoo111 thank you random dude on the internet with a blank profile pic with a W on it.

[@agifirmansyah1183]

@@n0us. D*

[@matsv201]

While i´m... well fairly smart.. i think the explanation was quite good and .. while its not obvious, it make sense at least to me. There is still energy to take out of the wind, even at higher then wind speed, but you would need a reference that is still lower than wind speed. The wheels make the reference of the prop lower than wind speed make it possible for the wind to push the vehicle over wind speed. The wind is not really pushing on the vehicle, it pushes on the reference speed of the prop

[@sarahbezold2008]

this is going to become a trick problem on a physics exam.

[@brianbeasley7270]

It already has been used for that in a physics contest environment by a group of physics teachers.

[@von...]

@@brianbeasley7270 were you in that group of physics teachers? something tells me maybe.

[@akunog3665]

@@von... I could be wrong, but I think he's referring to the video. The thing is built and argued about by a group of physics teachers if I recall correctly.

[@ShimmeringSpectrum]

I think "Airplane on a treadmill" is already a common physics argument and this seems like a variation on that theme.

[@GalacticalAmbassador]

Or the bonus question which is also usually the trick question

[@Sibl3o]

As a yacht racer and captain it took me 25 years to accept and understand apparent wind and going faster than the wind. So as a base level I think I already understand more than your average person. But I did have to watch every second to understand how this works. Mind still boggles.

[@stevesilsby5288]

This with the tremendous drag of pulling the hull through the water! It is indeed mind boggling.

[@arachnophilia427]

i was following this internet debate like 15 years ago, when it spanned three different message boards, including 30 maxed out threads at talk rational. i can't believe it's still going on. that fight was BRUTAL

[@cosmologicalturtle9528]

Imma be honest, I’m still completely lost on how this works. When the craft is going at the speed of the wind, isn’t it’s perceived wind 0? In which case, how is it able to be powered by the wind if it feels no wind?

[@milesgould8288]

@@cosmologicalturtle9528 the propellor is being driven by the wheels, which are being rotated by the vehicle rolling over the ground at nonzero speed.

[@billiondollardan]

I hate to upvote this comment because your username creeps me out! LOL

[@BenJamin-rt7ui]

@@cosmologicalturtle9528 If feels a net headwind. In which case why not just turn the thing around 180 degrees into a headwind? It should move forward, thus proving the point more easily.

[@thijsschipper7740]

@@BenJamin-rt7ui I think it's because the cart needs to be rolling for this effect to work, hence it has to be downwind to get its initial momentum

[@sdaniaal]

Mad respect to that guy Rick, first off for thinking of such an abstract concept and making it easy to understand (the cylindrical plane downwind explantion) and then for actually making, trying and testing his theory. I can't imagine how many people have disregarded or denied his work but am amazed he's persevered and made it this far, congrats on being an innovator!

[@ManuelPrenza]

I second this comment

[@Corianas_]

Multiple times even. First he made a toy and proved it, then when he had doubters he really proved it.

[@drenzine]

The fact that he ACTUALLY tested the theory and made a big version of the small one is epic

[@landenew]

these are the people that make revolutionary advancements in science

[@wyattb3138]

A real engineer

[@sikolikhole]

This broke my mind until you showed the sail boats in a cylindrical world. The creator explained it the best way, your addition of the animation helped tremendously. 👍🏼

[@weirdlingweirdo1058]

The wind drove the sales on the cylinder earth but the wheels drove the propeller to push against the wind. Sales don't push wind and they used a propeller like a plane trying to take off going in the same direction as the wind.

[@mgutkowski]

It's also a complete red herring if you pay attention to the direction of rotation. It's a prop, not a turbine.

[@Sp00ns655]

@@Goblineng they said in the video that the wind pushes the car, and the wheels drive the prop, but its geared up to make the prop spin faster, which to me seems fake because that would be a perpetual motion machine

[@weirdlingweirdo1058]

@The Ardent J so, the wind is pushing the vehicle the same way a plane is blown on when it faces with wind and turns on it's propellers to start moving faster than the wind.

[@sikolikhole]

@@Sp00ns655 the creator says it's a prop. The wind doesn't push the vehicle the whole time, it helps turn the sails into a prop.

[@naveenlp]

8:05 was my absolute favorite part of the video. jumping from an intuition to an abstraction to a mechanical solution. amazing stuff

[@louisgerber65]

As a sailor and physicist, the only one thing, that drives me crazy about this is that I didn't have this idea myself. The cylinder earth is brilliant!

[@jeremystanger1711]

Agreed - it's one of those rare moments of insight that really epitomises for me the beauty of physics.

[@JeroenDStout]

That is a really beauty, a cylinder earth being a spiral reference frame. French chef kiss.

[@sidewaysdesign]

I'm not a physicist, but the idea of the cylinder earth made it all make sense in an instant.

[@super0spore0fan]

I know, right? That explanation is straight up feynman-like!

[@theeternal6890]

*Aweseome.* Imagine if earth is flat tho.

[@rugbyf0rlife]

The way the creator explained the prop mechanic of a "cylindrical earth" is mindblowing, and that kind of out of the box thinking is the mark of a genius.

[@Douken]

That was the best explanation along with that animation.

[@zabu14]

flat earthers are.... geniuses?

[@grgr7377]

The simplicity and elegance of this man's idea is so brilliant I cannot stop smiling :)

[@alamtarokainkavan4524]

@@zabu14 Hahaha good joke, you got me there.

[@guest_informant]

That and the animation, the way it moves from the boat to the cylindrical Earth to the propeller. Incredible.

[@CMZneu]

The sailboats around a tube explanation is genius!

[@josephilip2136]

I didn't get that. But I got his explanation

[@richardbloemenkamp8532]

Maybe, but to me it has little relation to the experiment. Also I miss an explanation how a sail boat can beat a balloon straight down wind. There are no wheels and chain driving the prop or sail.

[@aspen9273]

@@richardbloemenkamp8532 it's talking about the idea of lift providing thrust, much like the propeller blades. Those examples were the proof of concept for the theory that led the creators to buold the vehicle

[@Dziaji]

But it has nothing to do with it because he said the wheels power the fan, not the other way around. This makes no sense and the video is garbage. The wind simply slowed down while he was riding.

[@AlloyDiesel]

@@richardbloemenkamp8532 Thank you! I am in the same boat. ⛵. I don't understand why the wheels are driven. You could essentially replace a sail with this prop and drive a boat faster than wind, so.. wheels don't seem to need to be driven. I don't buy the argument that the craft moves just because it is a bluff body either. It moves due to thrust created by the prop.

[@mantouedible]

Once you mentioned the "fan driven by the wheel" it really starts to make sense. Imagine that the fan is just a giant sail, then it would go down at wind speed; and by converting the energy at the wheel to the fan it gets this additional oomph that pushes it faster.

[@ОлександрХірх-Ялан]

sail size no matter if there is no wind that blow to it. When you moving at wind speed downwind - apparent wind from moving forward fully compensate wind and in propellers will be only apparent wind from its rotation. But there is drag in propellers so it will slow down, but no energy comes from wind and car will slow down till wind stars push it again. So it can't move faster. It it moving faster - aparent wind from moving with aparent wind from rotating - creates backward lift in propellers and it again slow downs. The only way how it is possible (and we see it in video) - if wind is slow down - car some time will move faster and slows down to wind speed.

[@famiguy4533]

@@ОлександрХірх-Ялан Nope. The wind doesn't slow down in the video. The wind is able to accelerate the car to a speed that is FASTER than the wind itself.

[@priestchatback]

@@famiguy4533Then why didn’t they show the actual wind speed during the demonstration? All they showed was the direction. If the wind dropped from 15mph to 12mph, that would explain the change of the flag on the front. Literally all they needed was a cheap speedometer and wind speed gauge to prove it works. And they didn’t use them. It’s fake and Derek fell for it.

[@ShaharHarshuv]

But it's not taking the energy from the wheel. If it has, the wheel would slow down. What Derek explained is that it's actually taking the energy from the wind, slowing IT down.

[@polkad3v]

@@ShaharHarshuv The propellors cutting into the air in front and pushing it backwards like a fan would, seems to be the faster than wind addition.

[@phrodendekia]

Man, the explanation of "if the earth was a cilynder" was so straightforward.

[@Kadranos]

I see what you did there.

[@90iatros]

But it's flat tho...

[@Plackomiot]

@@90iatros Thats why he said "If"

[@Kastnerd]

But why did he not bring that back up at the end of the video?

[@Neal_Sporin]

I think the inventor's sailing around a cylinder analogy is incorrect. He said that the two sails about a cylinder form a prop. I agree with that, but according to Derek, the prop is not acting like a sail in the windmill (airfoil) sense.

[@TKTrooper]

I felt the most happiest for the guy who dreamt this up, had the balls to share the idea and was then mocked for it, and called out as some kind of liar when showing a working model. Vindication feels good. Those are the types of people that push technology forward, by not caring what others believe, believing in their own ideas and just doing it. Bravo Sir!

[@jasoncentore1830]

I'm glad it worked out, people love to mock and call people crazy for new ideas. Look at all the famous inventors, etc lightbulb, cars, phone, etc... These were all "Nuts" according to people that don't want to understand. Einstein and several others were deemed crazy, I wish they were alive to say FU.

[@kt.7257]

@@jasoncentore1830 one more of Thor's people that was mocked was Nikola Tesla

[@Rick_Cavallaro]

@@kt.7257 Unfortunately Tesla was both a genius and a crackpot. He deserved both the adulation and the mocking at times.

[@spider0804]

Welcome to science and going against the grain where you are ridiculed and derided for years and years until you can prove the concept or give up and live in shame. Science is great, people are not.

[@peterisawesomeplease]

This is misleading. The first of these was built in the 60s and it's a mildly popular physics puzzle. The comments are mostly just people trying their best to understand.

[@fedbia2003]

“Is it safe? It feels makeshift.” The hallmark of any proper, reliable machine.

[@notmilandia8461]

It looks very Mad Maxesque.

[@celebrim1]

What real science always looks like.

[@fedbia2003]

@@celebrim1 Lmao, that's true.

[@guotyr2502]

Sounds like progress to me

[@radialbladeworks6183]

*Mercedes drivers getting behind the wheel of a BMW*

[@RaccoonHenry]

the animation of the cylinder earth and the two sailboats made it just CLICK in my brain. instantly. I even WOAHd out loud!!

[@maloxi1472]

That's it Derek, you settled the debate: *I'm a Cylindrical Earther now.*

[@Rick_Cavallaro]

I think maybe I need to make cylindrical Earth T-shirts with two sailboats circling downwind.

[@toddthecarver]

😜😄

[@davidhollenshead4892]

That thought experiment works for showing how the propeller is working on the cart. Of course, if you know how to sail, then you know how it works...

[@i_g9854]

😂😂

[@steveperreira5850]

Unfortunately, I had to explain to my 25-year-old daughter that the world is not flat after she read about the flat earth theory on the Internet. I was so sad, but she came around soon enough. And now I am confronted with the cylindrical earth theory, and I am Starting to fall for it. Ha ha!

[@JNCressey]

everyone: the earth is a sphere flat earthers: the earth is flat this guy: imagine the earth is a cylinder

[@THEMATT222]

Astronaut 1: Wait, it's all cylinders? Astronaut 2: 🔫 Always has been!

[@ardaozcan98]

Earth is L O N G

[@rngiscurse]

Welcome to the l o n g Earth society

[@The_House_Always_Wins]

IT ALL MAKES SENSE NOW!!

[@zagorim7469]

nah the earth is an irregularly shaped ellipsoid. No i am not fun at parties. what's a party anyway ?

[@ujustinree2987]

that idea of the cylindrical earth and two sailboats being like a propeller was genius

[@someting9205]

Yeah, just like flat earth right? Or climate change.

[@anthonygordon4515]

Just change your name to “that guy” after that

[@someting9205]

@@anthonygordon4515 no im THE guy faking ur moma

[@someting9205]

@Kian Woods ikr these people believe anything. If this channel make a video about flat earth all you brainless would buy it lmao

[@arck4453]

@@someting9205 I mean, I'm not a physicist, so idrk. But, you could also share your opinion instead of that free hate.

[@SahilP2648]

This is basically how a boat is always in equilibrium with the water because of the water surface area's lift which changes in proportion to how much the ship sinks when weight is added to the ship. This vehicle is in equilibrium because of the weight (especially the one on the treadmill) since it's so light. But unlike a ship that can stay afloat with weight change, this vehicle won't be in equilibrium anymore once more weight is added to it. When that vehicle is on the treadmill, the treadmill needs more energy when the vehicle has the propeller than wirhout. For the treamill, the vehicle is a little heavier (not technically, only intuitively) because of the propeller pushing it, causing more friction and more resistance, causing the treadmill to skow down, as if a wheel was going opposite the treadmill causing it to slow down. So the treadmill spends additional energy in this configuration which leads to the propeller. Again, the vehicle is light, so it works. After adding some weight, this setup doesn't work anymore (like a badly shaped boat which cannot displace as much water weight as much as the added weight to the ship).

[@iamnorwegian]

That cylindrical earth argument was something really elegant and beautiful.

[@uzlopak]

So earth is not flat. It is cylindrical.

[@josephcarter377]

@@uzlopak ofc

[@ericvandenavond8748]

@@AstroCosmos nah

[@77payne]

trying to explain physics while wearing Heineken shirt. Nice

[@randellreimer2877]

actually I don't think it was. with that model, the forward motion of the boat/fan would be at most exactly the same as the wind speed, not faster. so it doesn't really explain anything.

[@ammonchristiansen4518]

"It's a little unbalanced, isn't it?" The entire propellor threatening to crush down on Derrick

[@ZaiyadR]

Very British of him, despite not being one

[@InvadersDie]

@@ZaiyadR BRI'ISH

[@qzbnyv]

@@ZaiyadR Is a fellow Aussie though so close enough! As are his kids now

[@wow-roblox8370]

@@InvadersDie that’s northern English. Not southern English. It is pronounced British

[@WilliamPitcher]

I watched a couple of videos on why wind turbines have three blades. I feel like this vehicle needed a three-blade prop.

[@NarutoUzumaki-vi4nf]

"Derek slow down" Derek: *I am speed*

[@consentofthegoverned5145]

Ca-chow!

[@volo870]

Imagine Jeremy Clarkson at the wheel?

[@julmaass]

@@volo870 imagine Richard Hammond at the wheel: How to total a one-of-a-kind vehicle?

[@kieranwalker2249]

4th comment I am speed enough to be 4th I am as speed as the 4th attempt

[@whosthis4850]

Ka mbn

[@pieppy6058]

Oh I finally get this. The wings turn because you move forwards. The wings then generate lift in the forwards direction which makes the wings spin faster. Nice

[@stephanequeval5330]

Hello: Yes but this part sounds so close to "perpetual movement". Where is this energy coming from??? The explanation comes later but this is so weird. I'm starting to get it..... slowly...

[@argentum4807]

The shot of the windsock going in the opposite direction to the string was amazing

[@FuncleChuck]

And yet it was meaningless. If the wind speed had dropped even a few percent in the moments leading up to this, he could be traveling at the same speed as the old wind (due to momentum), the string is super lightweight and would have immediately changed direction, and the windsock wouldn’t have even noticeably changed.

[@Crazy_Diamond_75]

@@FuncleChuck yeah but we saw it pointing back for several seconds prior to that event. I would think the craft would slow down after that much time

[@literate-aside]

Yes, it was.

[@thesecondslit1710]

It's actually all we need. Smoke would be cool, though ;)

[@compassionatecurmudgeon7025]

@@FuncleChuck Plus they could've just glued the windsock right. Or maybe the whole thing is CGI. You can tumble down rabbit holes for miles. It's not unreasonable to assume some element of good faith. It'd be a lot of work to tell a lie that will make the creators zero money.

[@idea-shack]

Scientists always say, "Extraordinary claims require extraordinary proof." This is a rare case of someone making that effort.

[@Justwantahover]

Exactly.

[@tuffdufroggin]

@@KINGJERMARCUS f off

[@padrickbeggs7071]

Derek* “I expect a lot of push back in the comments” The comments* “THE EARTH IS A CYLINDER”

[@happysongs4kyrone]

@annag cocl "Please be civil" understood, talk about dababy and amogus now.

[@bruceleealmighty]

I'm thinking that if you have 4 sail boats going around a cylinder, you can have 4 blades.

[@KleptomaniacJames]

@@happysongs4kyrone affirmative

[@bockariemansaray9196]

And i was told the earth is flat...... dang it! Lmao

[@bruceleealmighty]

Come on you guys, you know it's conical

[@mohammadsadeghi4202]

This setup is an active sail(s) combined with wills paired by an accurate rotation ratio I like to see if some telltale thing is placed behind the fan this fan is redirecting a large volume of air in another direction in a cone shape which a blackbird in the center of it This system will work as long as the wheels are on the ground. Rick explained how it worked, clear in minutes 8:00 to 8:30.

[@JaceDeanLove]

I like large Valium

[@coleballenger4595]

@@JaceDeanLove Me too bruh. Me too.

[@XxjeffersonDkidxX]

"Slow it down derek!" Derek: *"i'm speed"*

[@PennyTradeYermum]

Dude was an absolute maniac. I thought he legit went insane when the camera shot showed him completely unfazed, then crack a smile.

[@EmeraldLavigne]

**GOTTA GO FAST!**

[@AxxLAfriku]

I HATE people that HATE other people. The comment I respond to did not spread HATE. That is good. BUT! I get a lot of HATE comments on my amazing videos and I HATE it. Please don't start spreading HATE. Do I have to HATE you too, dear jerr

[@mikaschmidt2110]

lmao thats exactly what I thought to myself when I saw that

[@ekaos5099]

@@AxxLAfriku Just hate yourself and then the world will be cool!

[@LeventK]

"If I want to slow down at the end, I pull it back. Right?" Famous last words of Veritasium

[@dharshiniiyer9925]

That's what she said

[@juijani4445]

Levent!!!! You're everywhere!!!

[@sumir]

That's what *he said 😉

[@quasarstarpower2858]

Hey, fancy seeing you here. :)

[@TrangleC]

"I'm excited to survive!" Would be much better last words.

[@VaraNiN]

I've done my BSc in physics last october and this has been the first time in years where I had a true mind = blown moment when it comes to something physics related. How I missed that feeling; that's why I started studying it in the first place. So thank you so much for this!!

[@Aethereus69]

I feel you, universities don't really try to open (and blow) our minds like that

[@Nomen_Latinum]

@@Aethereus69 It's worth noting that there's not much universities can do about that. A major in physics involves a lot of dense mathematics and many different fields to tie together. There's very little room for recreational physics there.

[@zumbaboy6500]

And did you already figure out a good hypothesis? The fan is simply a store of energy that is later used again to accelerate the car, the pitch of the blades is probably determining whether or not energy is stored into the fan or transfered to the cars acceleration. It's literally like charging a battery when going slower than the wind and then using that energy to run a fan to accelerate beyond wind speed. Instead of a battery the energy is stored in the rotation of the fan itself.

[@ThisNoName]

@@zumbaboy6500 Not that scientific. It's just like sailboat tacking, half of wind flow over the airplane wing shaped sail generating lift, making boat zigzagging faster down wind. I think the genius idea is to gear the propeller spin backward, which simulates the tacking effect on a straight line.

[@jpkriel9141]

Dude thats one of many things i love about your channel,you explain things in a way that someone els can explain it to a child and even they get it then. Coedoes to you and your team,plz keep up the good work💯

[@katzen3314]

The sail boat metaphor was really clear, everything just clicked for me after that.

[@0masuk0]

If you trust the intial claim that the sailboat can go faster than a wind in a direction of a wind. Sidewise - sure. I do not think projection of a velcity on wind direction is able to overpass wind velocity. Also this analogy doe not do work on why mechanical connection with wheels is necessary. (Actually with boat reaction of an ocean to board pushes boat forward too, and this is discarded).

[@poikoi1530]

@@KINGJERMARCUS tf

[@Ddeletham]

@@0masuk0 as someone who sails I can say it truly works that way. Probably makes this whole thing a lot more intuitive, too.

[@970357ers]

@@0masuk0 Did you watch the whole video? The balloon Vs tacking sail boat thought experiment was discussed in detail.

[@akunog3665]

@@0masuk0 a good sailboat can go downwind faster than a balloon by clipping. Also, imagine the speed of the blades of the turbine/fan on the car. The blades are moving much faster than the wind, just not in the same direction. The movement of the blades is analogous to a sail boat clipping the wind at some angle (angle is controlled by the left level in the driver's seat). This speed is transmitted to the wheels. It's a bit odd for sure.

[@pianomail]

As an Aerospace Engineer, first thought was absolutely, no way this works. Then I remember tacking sailboats, right before you mentioned them, and thought, okay maybe this is possible. The last explanation was fantastic and clearly demonstrates it is possible. There is a lot of energy in that wind, the propeller just allows you to pull a bit more energy out than you would otherwise be able to.

[@slavka012]

OMG tacking sailboat moves faster than wind but not in the direction of the wind. It still can't outpace a drifting balloon.

[@strehlow]

@@slavka012 A tacking sailboat can outpace the wind when done correctly. That has been demonstrated many times, and was referenced in the video.

[@pierregrosjean6355]

19:52 "2.8 times the wind's speed" Come on, as an Aerospace Engineer you know it's bullsh*t...

[@pianomail]

@@pierregrosjean6355 it's not "bullsh*t". I'm currently halfway done my Masters. Just because it doesn't intuitively seem plausible to you doesn't mean it isn't. It makes perfect sense once explained.

[@slipsonic809]

That's kinda how I understood it at the end. If it was a closed loop and the only wind that existed was the wind that actually interacted with the vehicle, this wouldn't be possible, But there's a constant stream of wind coming from behind, not to mention a whole lake bottom worth of wind all around. If you could instantly harvest the energy from, say, a 1km long 20m x 20m tunnel of wind, the vehicle could probably go 100kmh + ( I'm not a physicist so the math is far beyond me) This thing just harvests the wind more efficiently, and the inventor is a very smart person. I said "holy crap" out loud when I saw the illustration of the two sailboats tacking around a cylindrical plane in the form of a propeller.

[@blampfno]

"To steer, push back on forth on one of the levers. To stop, pull on one of the other ones. Probably" --The Designer, probably

[@E1craZ4life]

If I ever made a steerable sled, I’d have the steering be controlled with two cords; pull one or the other to steer, and pull both together to brake.

[@thehatred94]

@@E1craZ4life i believe the point is to NOT brake too fast. So if you're going faster than the wind, you want to slow down rather than hit the brake, less something break or you tople over. Hence why you need to turn wichever direction make you slow down more. But that all was probably mostly humor. Just turn a direction and proceed to slow down is the thing to do... less it's an emergency and you're better off toppling over.

[@isaacchock7678]

I had the same problem happen to me in a middle school science class… teacher asked if a plane could lift off if it was on a treadmill going backwards as fast as the plane going forwards. If the speed came from the propellers and not the wheels then it shouldn’t matter if the wheels were turning backwards… I was the only one in class saying the plane would lift off. Interesting thing (taught me a lot about people) is that I got threats and was even on the receiving end of violence when I would not change my stance. When we watched a mythbusters video that showed the plane did lift off they still wouldn’t believe and continued to threaten and bully me. Perhaps the most dangerous people in our society are the ones who think they know and will not listen.

[@robde-e-e]

It will only lift of if there is enough friction between plane and treadmill, because only then the props can move enough air around the wings without the plane going forward. I think...

[@virenor]

When the violence reaches the stable state of full development, its initial cause becomes irrelevant. In other words, people just like to kick someone's ass, and proving them wrong makes the situation even worse.

[@yujinhikita5611]

i dont quite know if im understanding it right, do you mean the plane is standing still in comparison to someone not on the treadmill? or is it moving? because my understanding of lift is when you have air flowing over and under the wing and if you arent moving through air you dont have lift, the treadmil isnt moving the air only the ground. im confused here. edit: so i watched the video from myth busters. the plane is moving through the air so obviously the plane will take off. however, the question makes it seem like the plane wont have any relative speed thus obviosly it wont take off. the question is bad. the plane in myth busters takes off because it has wheels, and the forward thrust is stonger than the backwards pull. if the aircraft was designed to fly slower and has a weaker engine than the car could pull under it the plane couldn't fly that is also if the aircraft has no enertia or the wheels have alot of friction. frankly the whole thing is just a trick question.

[@virenor]

@@yujinhikita5611 Yes, the whole thing is about analyzing the mechanics and realizing, that most of the energy of the treadmill would be lost, so propellers would produce enough force to overcome it, but this applies only to actually existing planes put on reasonably feasible treadmills, but not all the theoretical objects and conditions we could possibly test. This makes the question quite pointless.

[@jmodified]

The plane can take off if it has sufficient forward speed relative to the air. How fast the wheels are moving is inconsequential, unless it is on a treadmill moving so fast that they burn up while most of the weight is still on them.

[@BomberTVx]

Veritasium: "How do I stop?" *The creators watching each other akwardly* "We don't do that here..."

[@donutzzs]

rip INGILIS

[@harsh3624]

@@donutzzs we don't do that here.

[@sudhirchaudhary6512]

@@harsh3624 😂🎃

[@kebabgud]

All wind, no breaks

[@YourEnvironmentSeattle]

My favorite moment hearing about a nuclear thermal rocket was the answer to the question "how do you turn it off?" Answer: releasing containment will quickly end the criticality.

[@sweney7103]

the cylindrical sail boat model was genius

[@elliotb1001]

Yeah!

[@Bardmusic66]

Yeah that made perfect sense and was easy to understand

[@warwickhs1]

It's a very old concept.

[@AlexandrBorschchev]

i dont get the connection, can someone explain?

[@andremarques3317]

i was like "ok so they are just making a comparison between sailboats and the black bird", and then it was actually an explanation showing its exactly the same principle

[@DrDeuteron]

The jump from cylindrical earth to prop is pretty much the spark of genius.

[@rizkim2664]

Yeah, it beautifully make me think that guy have a point. It may be wrong, but it really intuitively believable.

[@RainAngel111]

That part literally blew my mind. Just jelly up there now

[@SidIcarus]

100% By that point I had an intuitive sense that it would work but couldn’t grasp why. That was a bit of a “ohhhhh” moment

[@xfallofmanx]

Yeah that was the point I was like “oh” and I turned the corner to grasping it.

[@3l84r70]

that's how I understand it... the propeller is nothing more than the two sailboats moving on that cylindrical earth, and the axis of the propeller is the cylindrical earth.. if sailboats can move faster than the wind, so can this... but I have to agree that that analogy and reshaping earth is the stroke of genius.

[@zimzimal8547]

Always love when people prove other “know it alls” wrong

[@kornflakesss]

Fax. But you gotta love these know it alls. They help these geniuses push the human race forward.

[@TeIwiNgaroRameka]

I love comments from "know it alls" where you can clearly tell no research was done at all...

[@jacobgoodstone7572]

@@TeIwiNgaroRameka Ah, yes the "I looked it up" people. Or the "I think that's true" people

[@normvargas2799]

It is glorious to watch.

[@Lebenspiel]

Derek: "How can I halt this thing? Inventor: "You must figure it out by yourself."

[@paunstefan1]

The halting problem.

[@virutech32]

Derek: yeah sounds legit, lessgo

[@cheesus8594]

@@paunstefan1 a Turing complete vehicle

[@AnonymousMycologist]

@@paunstefan1 You made me laugh. Thanks :)

[@Reisboy_PhD]

best answer ever

[@hydewhyte4364]

Proof that there's still room for the back yard scientist.

[@dah_goofster]

Even the meta scientists of today started in their backyard

[@Raymo2u]

Dont question accepted science though, or your crazy and a conspiracy theorist.

[@beansssss3847]

@@Raymo2u dont be bitter, show up with evidence that established science is different or grumble back to the lab

[@rtg5881]

@@beansssss3847 Its not establlished science that is the problem. Its what counts as established in the mainstream and its not what the research says or even what the scientists say (which even that would be personal opinion, not research) but what the media says about what they say. At most reading a title or an abstract, certainly not lookng at the methodology, the discussion pages or anything else relating to it for that matter. In other word, we are doing the work, in fact weve long completed and published that work before we publiclly disagreed (and not published in fake pay to publish magazines).

[@beansssss3847]

@@rtg5881 so what are you upset about exactly? that your findings are being wrongly presented? confront the journalists publicly since you would have the appropiate data. if you cant professionally fight for your research then im not sure youre really involved in any projects. the poster i replied to is obviously not one.

[@dexterm2003]

A cool related topic is that salmon actually use passive body dynamics to do a similar thing when the swim up stream. Researchers at my Alma mater Oregon State have been studying it. It would be cool to see a Veritasium video on that.

[@veritasium]

This briefly got a mention in my turbulent flow video: dead fish swim upstream

[@danieldimitri6133]

I was going to use this in my comment but came up with something easier to understand. Great comment though. A fish does not swim it is swum!

[@hyperfuzzysniper30]

Super easy barely an inconvenience

[@michaelakamatsu]

OSU BSME 1982. I'm trying to understand it out without watching the entire video. Still working on it.

[@begintothink]

This fluid mechanic is actually already used to measure flow in pipes. It's just neat to see that in nature. That is not perpetual motion though.

[@ウタ-u1g]

I love how simple questions and problems produces so beautiful answers and solutions. What a time to be alive

[@rahulb.329]

"I expect a lot of pushback in the comment section" The whole comment section: Wholesome appreciation of this marvelous phenomenon.

[@liambergstrom8183]

But a lot of downvotes on the video

[@simonci5177]

Design Flow! It's wrong turbine. Instal Vertical wind turbine instead horizontal. THAN It will create power on wind from Any direction. From front or back of the car... or even side of the car...

[@WunderWuzzii]

@@simonci5177 The prop is not used as a turbine, but as a propeller/fan. Wind pushes the vehicle - wheels start spinning and power the propeller - wind can push the car to windspeed - propeller "uses" the sailing trick to get the car faster than windspeed. That's why this only works with tailwind.

[@larsdahl5528]

Perhaps we can use that pushback to type comments faster than... Uhm...

[@WanderTheNomad]

@@simonci5177 I don't know about other people, but I tend to dismiss comments that are copy-pasted across multiple comment threads, no matter what the content of the comment is and whether it's done manually or by a bot.

[@whiteeaglewarrior]

This takes "someone was wrong on the internet" to a whole new level

[@PistonAvatarGuy]

These guys are living my dream.

[@anthonysgambati3683]

Your CG guy's pretty good. Pay him well and use him more. Everyone likes those helpful little animations that help visualize.

[@Jhawk_2k]

I thought you were going to say the CG guy is good because he animated a realistic vehicle that is impossible or something lol. But you're right, those visuals helped so much.

[@sentienttoyotacamry3283]

@@Jhawk_2k we are not that different

[@rv706]

Maybe he is his own CG guy, who knows...

[@shrekjunior6144]

@@sentienttoyotacamry3283 Yes you are

[@calebihrig2915]

You mean he didn't just grab open-source images from the public domain?

[@TwoMarlboro]

Looking at a sailboat, it's direction of travel is (neglecting drift here) determined by the hull's heading. For every meter the wind pushes the sail downwind, the boat must also travel x meters (depending on the heading) perpendicular to the wind. This is even more true for a land sail vehicle, which has practically no drift. The same happens with the fan-car, for every meter forward travel of the blade, the blade has to travel x-meters perpendicular to the wind direction. (In this case, in a circular path, instead of a linear path, nonetheless traveling in a plane perpendicular to the wind). The gear ratio between the wheels and the blade determines how much perpendicular travel will happen for each downwind meter traveled by the 'sails'. So with the correct gear ratio and with low enough drag, it is possible to have a velocity made good of the blades that surpasses the wind speed.

[@ActDontSpeak]

That shot with blackbird and the man holding that orange windsock, is so phenomenal.

[@papalegba6759]

it proves a battery powered electric vehicle can go faster than the wind. so what?

[@Dj-yq3un]

@@papalegba6759 you have proof this vehicle had a battery and motor?

[@papalegba6759]

@@Dj-yq3un 12:20 if you're not blind, deaf & mad.

[@rinislaboratories1315]

@@papalegba6759 everyone, allow me to introduce you to our modern frank burns

[@TheGunz0001]

@Wary of Extremes Good point, they should've showed on camera the windspeed comparison rather than offhandedly say they managed to travel 2x the windspeed. However if we agree that there is no motorized power acting on the propeller, there is no scenario in which the propeller is able to generate headwind upto the ribbon, and yet not travel faster than the surrounding wind.

[@manikandanm3277]

That shot at the finish line where telltale and windsock showing opposite directions was so cool.

[@samanjj]

Jaw dropping. It looked surreal

[@markoap91]

"If the Earth were a cylinder...", hey, don't give them any ideas!

[@muhammadhassaan4339]

you got my like 💀 we don’t even have to say who “they” are we just know 😂

[@THESLlCK]

Don't worry we're already at donut earth theory

[@Milesco]

@@THESLlCK : Mmmmm....donuts! 😋

[@StinkyScript]

elon musk: *interesting*

[@himanbam]

@@THESLlCK Maps on donut worlds need 7 colors. As opposed to maps on spheres that only need 4. So to know what shape the earth is, get a map and count the colors.

[@patrickoconnor3844]

I'm a physicist,but also an engineer. If it works and some people don't understand it, that doesn't stop it from working...

[@carykh]

I love it when the counter-intuitive answer is right! I wonder if this would work on the ocean floor, with water currents. There's more mass to push off of, but there's also much more drag...

[@brainmind4070]

Seems to require a smooth surface, so no, probably not.

[@StrikeNoir105E]

A lot of things in scientific discovery tend to be counterintuitive only because our understanding has yet to catch up to the actual reality. Only when our understanding has advanced enough can we adjust our intuition to work with the reality that is happening.

[@ricci8497]

Suspect it could be done but a lot more engineering would have to go into it as the waters going to create more drag plus cross currents and chop much higher risks. Would possibly have to tackle it from either making like a two or three hulled design to even going down the route of a hydrofoil but winds would have to be stronger.

[@brainmind4070]

@@ricci8497 Are you talking about a submersible that runs along the bottom of the ocean? I don't really see it being that feasible except maybe for some really flat, smooth areas. A boat would make more sense. You would need propellers or something underwater to drive the sails. Could be ducted to negate effects of cross-currents.

[@dreweab]

You can't get low pressure water so no it wouldn't work. Edit: I see there's going to be a lot of people correcting me so I'll admit my above statement is false. I was trying to make a point about something but I was way to drunk to articulate it clearly enough to be useful and now that its morning I have no clue what it was about. I will leave the original so that the responses makes sense. Science > ego. Admit when your wrong and the world will be a better place.

[@ninjaasmoke]

When these guys say, "For science" and do something crazy, IT'S ACTUALLY FOR SCIENCE

[@kevinh6008]

I'll be honest, I think that the word "science" is misused here. This is a feat of engineering. I don't think any new science was done here.

[@scetmam1031]

@@kevinh6008 yeah but, FOR ENGINEERING! Doesn't quite feel the same.

[@RED40HOURS]

@@kevinh6008 *for science*

[@thanosmom9118]

Scientific engineering

[@bhargavshekhar3745]

Haha true bro

[@sofiarocha9907]

The one thing I like more than science made out of curiosity is science made out of spite! Great job, guys

[@happysongs4kyrone]

Spite-science

[@adamgardiner5869]

Lady, I love your comment.

[@EneaG]

so basically how space exploration started lol

[@craighaldane3596]

Amazing. One of the best things I've seen for a while👍. Absolutely loved it.

[@North7able]

Lazy Physics Teachers: "Can't be done." Crazy Desert man: "Hold my beer."

[@martymodus7205]

Physicists should be skeptical of a claim like this without a mathematical or physical model to demonstrate that the claim is true. So, perhaps an appropriately skeptical physics professor rather than a "lazy" one. ;-)

[@frissonsknives]

Hahahaha

[@12footstroke15]

Sounds like Marty may be a physicist

[@collinsmcrae]

I think the criticism against the professor was more to do with what they had to say about the treadmill.

[@Ronnypetson]

In this case, "Hold my Heineken".. the dude was wearing it

[@wafkt]

Several times throughout that video I was like, “oh! That makes sense, I get it now,” only to be like a few moments later, “ah? Yeah, I don’t get it anymore.”

[@WilliamPitcher]

Just sitting on the cusp of understanding is frustrating too. I think I would have been lost if I hadn't already learned that propellers are like wings.

[@jcims]

Same. It's a very slippery concept. I'm just glad these guys were able to hold it together long enough to build it.

[@frostburnspirit9065]

nothing made sense to me

[@Yora21]

I still don't actually understand lift to this very day. But it's what makes planes fly and ships sail faster than wind, which is happening everywhere every day.

[@EmeraldLavigne]

Ditto & I wound up at "I don't get it anymore," at the end of it all.

[@low-key-gamer6117]

physicist, "nope not gonna work" engineer, "Imma assume the earth is like a cylinder"

[@RoseSiames]

Oh how the tables have turned

[@chasbianco142]

Oh how the turn tables.......have

[@MrSeppei]

Who is a real scientist now, HUH?

[@TheGedas]

Same engineer "also lets assume pi=3"

[@HideFromIt]

@@TheGedas easier to memorize

[@lawrencekoestler742]

It's like paddling a canoe with the current.

[@vincentkosgei7166]

You are adding an additional power by padding,

[@reanetsemoleleki8219]

It started to make sense to me when he explained the cylindrical earth/boats as propellers metaphor.

[@gl0wingice]

once he mentioned boats i was like, of course! boats go faster all the time by tacking! than the 2 boats on a cylinder it made complete sense.

[@temporarytemp5930]

It vanished the moment the sail became fan.

[@OneThousand98]

That was actually a really bad metaphor since the propeller is not acting like two sails it's acting like a fan, the exact opposite of two sails.

[@rsporsche]

​@@OneThousand98 But as they said, the boat is also travelling faster downwind than the wind. It's the same concept. The only difference is that the propeller is driven by the wheels and in the case of the boat it's driven perpendicularly to the wind by the centreboard and rudder.

[@pedrorequio5515]

@@rsporsche I have a massive problem with the fan analogy in this video and I explain why(it is obvious it's possible just the explanation is off). A fan in a traditional sense is a powered device if you are using the wheels to powered them them the fan is not pushing it is actually acting as a brake, in fact if there is no wind at all this will inevitably happen. No the wind is actually still the main power source here, much like in the way that if there is no wind you cant do it on a sail boat. I believe if I made the energy equation we would arrive at two distinctive situation one before wind speed and after, because apparent wind speed changes. The aparent wind changes but now much like the boat it is down wind which is a possible case because of the Coandra effect diverting the air, so it is a fan but it is not the wheels powering it, it is still the wind. It makes me wonder what would happen at exactly wind speed there would be none of either but the boat still breaks the barrier that is where my knowledge end. But I'd like to add this I believe because the sail(or propeller blades in this case) are big the configuration on wind speed is unstable because it is either going to slow down or speed up, can it be that the moment wind speed is reached inertia on the wheels actually turn the blade against the expected outcome of stopping, this I don't know. But I stress, I am not an expert.

[@NelsonBrown]

I forget who said it -- several years ago -- but went something like: "Sure they made it work in practice, but can they make it work in theory?"

[@juandelacruz2343]

Michael of Vsauce also said that when he collab with Adam Savage, i think it was the brachistochrone curve episode

[@bxlawless100]

That reminds me of the quote, “heavier-than-air flying machines are impossible”

[@anonymouse9105]

Bicycle: "Are you talkin' to me?"

[@mixer6166]

After a lifetime of experiencing the experts failing at countless numbers of their own predictions, while simultaneously mocking the ideas of people less accredited who actually changed the world, here's a prediction based on scientific data. The experts will be wrong. And the more of them that agree the more wrong they will be.

[@furyking380]

The way they tell the story it sounds like they had the theory part down first, then built it afterwards. More like theoretical physicists discovering black holes than the Wright Brothers building airplanes

[@umountable]

The analogy with the sails makes ist quite clear, but its still mindbending.

[@halfeld]

But the "propeller" pitch in that analogy is inverted, is it not?

[@Toobula]

That was the explanation that clicked for me. The mind bend is the same as a sailboat tacking into the wind. A broad reach (tacking with the wind) is no different.

[@anevilrotisserie9136]

How?

[@Rick_Cavallaro]

@@Toobula Right - a sailboat tacking into the wind is actually going "down current faster than the current". Again, it's all a matter of reference frames.

[@wasd3108]

But if you have a inverted pushback propeller being perfectly balanced on top of a analog downwind current stabilizer, it still makes it mindbending, still does not explain why my ice taste like water.

[@HotNoob]

the fan lowers the wind speed delta behind it, thus allowing it to move faster.

[@LeventK]

"If I want to slow down at the end, I pull it back. Right?" Famous last words.

[@UhKimboze]

No replies to this comment, I’ll be the first.

[@seeker1015]

It reminded me of an Abbott & Costello sketch; "Go ahead, back up."

[@ResearchAdvantage]

“Perpetual motion” and other free energy gimmicks assume a closed system; this device functions in an open system in that the moving air stream is not limited to the region occupied by the vehicle. The “fan” creates a pressure gradient that is resisted by ambient pressure in all directions, so the vehicle is forced to the lower pressure ahead. More like an ice boat than a sailboat. The reason a sailboat can sail into the wind is because of the keel (or skates for an iceboat) and the resistance against lateral motion they provide. Downwind they sail at an angle to the wind. The wheels on this craft resist everything but going straight ahead. Wheels extract energy from every revolution to transfer to the propellor. It has to start with a push, either from the wind or by hand. After that it is up to the operator to control the propellor pitch, just like sailing, to optimize the thrust.

[@800mpro]

Exactly.

[@DeathBringer769]

Yep, there's no "free" energy here. It's just energy transfer in a way that seems counter-intuitive at first.

[@geraldfrost4710]

I'd like to see a second telltale, something at the height of the top of the blade reach. Wind speed at ground level isn't the same as wind speed higher in the air. Not denying the video, just wanting a bit more data. If the wind speed at the top of a mast is higher than at the bottom, by how much? Make it a thin mast; I don't want to add more drag to the system; I just want a bit more data.

[@Hidden_Seeker_]

Great explanation

[@randomuser5237]

Not that simple. It also has a lot to do with the gears that connect the wheel and the propeller. This needs to have some minimum gear ratio for the wheels to overcome the propeller torque. With a reverse gear ratio it will move in the opposite direction.

[@The8BitGuy]

So, from an energy perspective, this might be analogous to converting low volts/high amps into low amps/high volts. The higher voltage can run a motor faster, even if it has less power. But I have to admit, this contraption seems crazy.

[@mreese8764]

Yes. It is an impedance transformer. The force acting against the propeller, in the direction of travel of the cart, is smaller than the force created on the wheels. So the cart moves forward even against the headwind in its frame of reference. An the velocity of the propeller and the force on the blades perpendicular to the direction of travel multiply to a large enough power, transmitted to the wheels, to push the cart forward. The propeller only creates low friction in the direction of travel of the carts but pics up a lot of energy perpendicular to it, moving the cart forward. The tacking around a cylinder world model works really well here.

[@Dude105tanki]

Didn’t expect to see you here... hello there lol

[@AppliedCryogenics]

Or a physical analogy, momentum is conserved, but momentum is a product of mass and velocity. If the mass goes down, the velocity goes up. Love your show, David, btw. Longtime subscriber!

[@LokiCDK]

I like this concept, this should be further reviewed, especially since, essentially, while wind is low, they couldn't exceed wind speed. They need to reach that critical conversion point where the the energy translation happens more freely.

[@sectumsempera123]

@@Bikonito He didnt you weirdo 😒😒

[@davidcurd987]

Another way to think of this is in terms of air pressure acting on the wing surfaces of the propeller it may make more sense. A sail boat going straight down wind reaches its maximum speed when the force from the difference in pressure from the back to the front of the sale equals that of the drag of the boat. By using the forward motion to drive the propeller from the wheels the pressure at the back of the propeller stays higher than if it were not rotating. Therefore, a pressure difference (and therefore a force) between the front and back of the propeller remains even above the wind speed.

[@normvargas2799]

I think this is the part that people can't understand. The turning of the prop increases as the speed increases so the prop is always pushing against the wind and always has a net force backwards. It is not a sail other than when going slowly , nor is it a windmill catching the wind and rotating because of it. It will only stop accelerating when the air resistance of the speed of the vehicle and internal friction exceeds the push of the propeller.

[@seminark]

This reminds me of that one kid who went against the entire class's answer and ends up getting it correct.

[@SpockAndStep]

it do have that same energy don't it

[@CanariasCanariass]

It do be like that

[@bearbryant3495]

Yeah, that was me, Mr Professor.

[@francoismarais8481]

great to see people without masks. great vid. very interesting!

[@mickys8065]

@Paul Martin technically, there were submarines all the way back to ancient greek / roman times, its just they barely ever worked, often poisoned the crew and were often just upturned boats with weights.

[@JoelCreates]

Sort of like inducing current from the environment then converting it to a higher voltage, love it!

[@afankhan7732]

Yeah, it's a reasonable explanation...

[@texrex1381]

awesome explanation! The voltage increases but power remains the same

[@_Nibi]

@@dsdsspp7130 I’m guessing you didn't watch the video...?

[@shivdeshpande1898]

That's cool! nice explanation ...

[@Rumpleforeskin338]

I believe the wind acts like an initial power source for the turbine car spinning the car's turbine faster and faster and consuming more wind at the same time. My guess is the friction upon the wheels would limit the overall speed needing more and more wind to go faster, but inevitably settling out as the wind cost is so high. This process would continue like the discharge of a high voltage transformer.

[@Dave_the_Dave]

The fact that you can sail in the opposite direction of the wind even on an angle, says this should be possible. The guy's metaphor with the two sailboat along a cylinder is absolutely brilliant.

[@pilotneedsride]

Exactly. I think the upwind scenario can really make this clear. If a boat can sail upwind, what is happening from the winds inertial frame? For an observer floating along in the wind, the air is still and it is the sea that is moving. In this frame, the boat is sailing in the direction of the sea, faster than the sea. That alone proves it is possible.

[@carlgoutell6315]

The propeller makes it's own apparent wind much like the sailboat on a broad reach. The fact that the vehicle is able to maintain a straight downwind course while taking advantage of 'broad reach' speed enhancement through the geared wheels allows the machine to easily outpace the wind. Not sure if my explanation helps or not .

[@OneThousand98]

Brilliant, but wrong. That whole section of the video was totally incorrect and actually a red herring. The real way it works has nothing to do with aerodynamic lift, and everything to do with static fan pressure.

[@johnsomerset1510]

It is complete BS, Dave.

[@johnborton4522]

@@johnsomerset1510 So of course with that same confidence as the professor you'll accept the same wager as the professor. Correct?

[@jaw3964]

Every so often this video pops up in my recommend. Ive watched it probably 5 times and still cant understand it. My mind instantly says thats not possible and refuses to acknowledge the concept.

[@likimark]

"If I put two sailboats, that's a prop" that was the clearest explanation. There is is a lift force in front of the propeller once it gets moving.

[@yrrahyrrah]

I would expect this to work even if the wheels and the propeller weren’t connected by chain. You just start going upwind, get up to speeds exceeding wind speed, turn the vehicle downwind without losing momentum and keep going. If sailboats can go faster downwind than a balloon, an optimized propeller car with less drag definitely can.

[@ninjaasmoke]

That was such a good explanation

[@kaspernordenram7832]

@@yrrahyrrah unfortunately that is not possible. The difference between this and the boat analogy is that, while the propeller rotates freely around the cylinder axis, the movement of a boat is limited by the daggerboards (water sails :)), which allow it to only move forwards or backwards (spiral around the cylinder). Projecting the force from the wing/sail on the degree of freedom, you can see that boats get a net force forward when going faster than the wind (not accounting for friction), while the propeller gets a net force slowing it down.

[@schipe]

@@yrrahyrrah This would be really interesting to build. Is it possible to build a ddwfttw kite with a propeller?

[@nathansukchai9415]

@@kaspernordenram7832 shouldn’t the axil and it friction to the ground via the wheels act provide that force

[@BS-vx8dg]

The cylinder illustration, coming after the visuals on tacking, is what made it click for me.

[@agentmiller4188]

Really? That didn’t do much for me

[@Chris-hx3om]

Yep, that was my 'ah-ha' moment too.

[@purplecharmanderz2975]

Same.

[@27johnrick]

Same here. That wad pretty neat

[@andrewevenson2657]

See that’s what I thought, but that apology breaks down a bit when he explains that the extra speed is caused by the wheels spinning the propeller opposite of the wind. It’s not really applicable to the sail boat analogy.

[@_J4k0b]

I think the cylindrical earth with the boats which transitioned to the propeller was an important animation to understand the concept!

[@SlothPlayingGames]

Agreed. That illustration alone is the only thing helping grasp the concept of whats accelerating the vehicle

[@tisaconundrum]

I wonder if they've optimized the size of the sales/propellers to maximize the speed

[@LVLRAV]

@@tisaconundrum I bet they did.

[@mattbarnett6902]

It was such a great transition that I hate to say anything about it. Buuuut, the whole concept of the propeller craft wouldn't work on the ocean, because the wheels are connected to, and drive the propeller. But such a slick concept and animation, I can forgive it. Lol

[@jexaradonite5451]

@@mattbarnett6902 it might work with a water wheel but then you have to deal with currents and the potential for the current to match the wind. Worst case you go at wind speed though so not terrible. also you'd have to find some way to deal with the torque of the water wheel combining with the propeller. It'd probably have to be really long.

[@gideonilm4983]

this observation might be interesting. The car is straight downwind, but the blades of the propeller are at an angle. They resemble that of the sail of a boat sailing at an angle.

[@michaelm1573]

"It's like a coffin Shoddily put together" - total Savage to say that right in front of the builder and owner

[@BoleDaPole]

Yes let's not say sa*age.. it has racist colloquium for many colonized cultures throughout the age of discovery.

[@EnderBOT122]

@@BoleDaPole damn bro, you're savage

[@michaelm1573]

@@EnderBOT122 at first I thought he was joking but it looks like he flagged my first comment. It's crazy that people give power to these words go look up the word Savage in a dictionary and get back to me man people are ridiculous

[@fumotomo]

@@EnderBOT122 thanks cirno

[@EnderBOT122]

@@michaelm1573 i am extremely racist

[@jonnysinclair2186]

“Feel what’s slowing you down and do that”- an expert 😬

[@blackmber]

Basically sums up the scientific method

[@michaelwicker9538]

I mean, there's always something like that going on when new sub fields of engineering are developed.

[@papalegba6759]

@@blackmber it has nothing to do with the scientific method. why is this comments section filled with idiots?

[@God-of-War]

@@papalegba6759 I have no clue.

[@jknew1832]

@@papalegba6759 hypothesis formulation: pushing this lever forward will slow me down. Test: push forward. Observe: did it slow me down? Modify: if no, try pushing this lever backwards. Seems pretty spot on to me? Certainly plausible enough that anyone claiming it is the scientific method doesn’t warrant being called an idiot, enough so I might be tempted to make a similar claim of one who doesn’t see the connection…

[@613aristocrat]

I love how this was shot like a Mythbusters episode.

[@cally01]

I think that's just because it's in a desert 😂

[@jimwhitehead1532]

It was better than the last Mythbusters seasons. I stopped watching when it got tired and felt phony, staged.

[@justrightlizard]

The music they used instantly reminded me of Mythbusters.

[@jakefromstatefarm1405]

My thoughts exactly

[@KaitharVideo]

and the funny thing... didn't Mythbusters do "Plane on a treadmill"? It's not the same puzzle, but there's some notable similarities.

[@637man3]

20:22 the windsock and the telltale pointing at each other. I wish physics had been taught like this when I was in high school.

[@andrewlazy662]

Derek: am I gonna die from driving this? Also Derek: cruises at 6 mph

[@sleepylad9829]

@Eric Cartman which tbh is a cool way to die

[@automatescellulaires8543]

@Eric Cartman Silly man that though he could move faster than the wind, dies in the attempt to prove its claim against modern science

[@chongjoseph4723]

I'll be honest:It's clickbait, but not a bad one

[@Vid_Master]

Yea that felt so forced / cringy lol

[@RodLandaeta]

I guess if you have a tortoise running at you with a thermo-nuclear bomb about to blow up, you could also dissect the problem in a similar way. X: Am I going to die from a tortoise attack? Also X: tortoise cruises at 1kph (because metric is better)

[@Arsopu]

This is so cool, I remember when I was a kid and my dad would take us sailing and he explained this to me saying that this must be possible, this exact thing! It actually makes me really happy to see this show up on my feed and to know he was right, it’s really amazing. 25 years later my brain would randomly bring it up living on the water and having the thought come up randomly and quite often, ahh I can’t wait to tell him.

[@mackit]

That's a great story! Make sure to share his reaction!

[@alejrandom6592]

**happy science noises**

[@HOPPIRI]

Now this is wholesome.

[@verse8833]

Do one better. Show him the video

[@Lucy8HOX200]

Haha who else got to the end and was like: "*thank god he's still alive*"

[@Autotrope]

The yachts going around a cylindrical ocean sold it to me that this is possible. Realising that the prop is driven by the wheel explained how this vehicle recreates that. I realised that the wind needed to have been pushing on something that was stationary in reference to the ground, not the vehicle.

[@tapiocaweasel]

Yeah, that diagram instantly convinced me, case closed, it's possible. Maybe I'm weird, but I didn't really have that intuition that this isn't possible.

[@jama211]

@@tapiocaweasel Yeah, I didn't have an issue when I realised that the more energy from the wind you can capture the faster you go. If boats can do it at an angle, there's no reason this couldn't with a prop.

[@iMeatbag]

Precisely.

[@extradimension7356]

Yeah that was a good graphic ~ I didn't have so much of a problem with it either but from a "Different frame of reference". I believe the aerofoil cross section* of the wind turbine / windmill is pretty critical in the same way that Langley had flat sectioned propellers on the 'Aerodrome" (that didn't fly too well) VS. the Wright Brothers that understood that the screw propeller had to have an aerofoil cross section to generate additional lift. If a yacht can "do it" (go faster than the wind) with an aerofoil then so can can a screw turbine / prop with an aerofoil. I may be wrong but this is how I think of it. 1. Bicycle - most efficient machine in the universe -ish. 2. Aerofoil cross sectioned prop - capable of generating extra thrust or capturing more energy due to inherent pressure differential that it creates. 3. Put them together. 4. The wonder of gear ratios vs power and torque. Does make me wonder if an Autogiro(sp) ungeared to the wheels would work just as well ????? (Scratching chin ponderously ). _________________________________________________________________________________________ * If you had flat cross section props (like Langley) the "Craft" would not achieve it's goal nor exceed the speed of the wind. ** What-a- bout vertical turbines/ mills - like the Cousteau Yacht ?

[@patrikhagne9204]

I was about to write the same. Brilliant analogy.