Risking My Life To Settle A Physics Debate

Everyone will say this craft breaks the laws of physics. This video is sponsored by Kiwico, For 50% off your first month of any subscription crate from KiwiCo (available in 40 countries!) head to www.kiwico.com/Veritasium50

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A HUGE thanks to Rick and Neil for letting me drive Blackbird. Check out Rick's HRgreen Channel for more in depth videos and explanations on going faster than the wind downwind -- ve42.co/Rick

Gene Nagata made the shoot possible. If you’re a video nerd like me, check out his channel, Potato Jet: hrgreen.infof... .

Xyla Foxlin for made the model cart used in this video. Xyla builds amazing things like rockets and canoes, check it out! hrgreen.info

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References
Jack Goodman's HRgreen video -- ve42.co/Goodman
Rick's treadmill footage -- ve42.co/Treadmill
Rick's multiple explanations of how Blackbird works -- ve42.co/DDWFTTW
Forum discussions -- ve42.co/forum Blog -- ve42.co/blog1 and retraction ve42.co/BlogRetraction

Gaunaa, M., Øye, S., \u0026 Mikkelsen, R. F. (2009). Theory and design of flow driven vehicles using rotors for energy conversion. In EWEC 2009 Proceedings online EWEC

Md. Sadak Ali Khan, Syed Ali Sufiyan, Jibu Thomas George, Md. Nizamuddin Ahmed. Analysis of Down-Wind Propeller Vehicle. International Journal of Scientific and Research Publications, 3, 4. (April 2013) ISSN 2250-3153. (www.ijsrp.org)

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Special thanks to Patreon supporters: Bill Linder, Paul Peijzel, Crated Comments, Anna, Mac Malkawi, Michael Schneider, Oleksii Leonov, Jim Osmun, Tyson McDowell, Ludovic Robillard, Jim buckmaster, fanime96, Juan Benet, Ruslan Khroma, Robert Blum, Richard Sundvall, Lee Redden, Vincent, Marinus Kuivenhoven, Alfred Wallace, Arjun Chakroborty, Joar Wandborg, Clayton Greenwell, Pindex, Michael Krugman, Cy 'kkm' K'Nelson, Sam Lutfi, Ron Neal

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Thanks to James Lincoln for building the initial prototypes for a model blackbird.

Written by Derek Muller, James Lincoln, and Petr Lebedev
Animation by Mike Radjabov and Iván Tello
Filmed by Gene Nagata, Derek Muller, Trenton Oliver, AJ Fillo and Emily Zhang
Edited by Trenton Oliver
Music from Epidemic Sound epidemicsound.com
Additional video supplied by Getty Images
Produced by AJ Fillo

Komentari 

  1. Veritasium

    Veritasium

    Prije 18 dana

    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).

    • Aryan Komati

      Aryan Komati

      Prije 16 dana

      I'm mind blown

    • Rick Cavallaro

      Rick Cavallaro

      Prije 16 dana

      @дмитрий иванов >> How does the structure behave in calm weather? It just sits still in no wind. Or if you prefer - it can go 3X wind speed in 0 wind. :)

    • Noguffay

      Noguffay

      Prije 16 dana

      @eyytee "MIT aerodynamicist Mark Drela : "In my view, the most closely controlled and unambiguous DDWFTTW demo is the cart climbing up the tilted treadmill." in the article: "What I’ve Learned About Wind Carts" by Mark Frauenfelder" Here's what I think "could" also work, though some people would still think that there are too many potentially hidden energy imputs being applied to the vehicle. Use the treadmill apparatus, sure, but in a different way, completely level. Just to prevent the vehicle from rolling forward, at first, when a fan starts to apply wind velocity/pressure from behind (I mean there is only a limited amount of runway on a treadmill). At some point as the fan is being ramped up in output air velocity/pressure, the vehicle is going to start rolling forward. At this very precise moment, stop the fan speed increase and hold it at that point (showing the audience that the fan is no longer being ramped up). Now also at this very precise moment start the treadmill to keep the vehicle in the center, by gradually ramping up the belt backward rotation in unison with the vehicle's tendency (now that the wind is pushing it forward) to NOT roll forward. At a very precise belt velocity, we will witness that the vehicle is not continually accelerating indefinitely, that the fan is set at a very precise velocity. We will be able to measure and record the vehicle speed in relation to the belt's m/s. We will be able to measure and record the velocity of the wind in m/s and compare the two. Simple. But, again, some people will think there is hidden inputs. This is why a tunnel/pipe with nothing but a fan, a vehicle on a rail (keeping it straight and giving it the wheel to ground contact required for rotation) would/should sooth these people's suspicions.

    • Papa Legba

      Papa Legba

      Prije 16 dana

      @Fred Meister look up mechanical doping in cycle racing then tell me he checked properly, science-hating crackpot.

    • Joeri sol

      Joeri sol

      Prije 16 dana

      It still does not explain why the speed of the prop is accelerating instead of decelerating when the vehicle is slowed down.

  2. David Sjöberg Bodaskolan 7-9

    David Sjöberg Bodaskolan 7-9

    Prije minute

    Would this work for a solar sail in space?

  3. bear

    bear

    Prije 6 minuta

    your explination kinda confused me by saying the air molecules behind the fan were giving energy to it. wouldnt it be the air in front of the fan giving kenetic energy to the sails (props/fan) and thats why there are slower behhind the fan? the props are the sail boats, the air in front is generating wind like they are tacking. they even can be adjusted to go faster or slower w/ the angle they attack the actual wind. so its not a perpetual motion machine. its a giant land sailing boat. which requires more than 10mph to go faster than wind apparently, and caps out at 2.8 times actual wind, from their testing. its cool they made it but it obviously doesnt break the laws of physics or establish new ones. and its obviously not a perpetual motion machine. not sure which forum they were posting on that trashed them before tho

  4. Ahsan Shahzad

    Ahsan Shahzad

    Prije 14 minuta

    I have an objection sir. the air particles behind the propeller are slow but particles in front the fan are still have the same speed. so the stick with clothe on it have to show its direction as the wind original speed because clothe is there, where the particles have the original speed nat the slower speed like particles behind the propeller.

  5. David Marshall

    David Marshall

    Prije 32 minuta

    The issues I have is that there's no mention of the props motion relative to the air (the air speed the surface of the prop sees is going to be faster because of the rotation of the prop) and also the aerodynamics of the prop acting like a sail (or rather an aerofoil), generating suction (i.e. thrust) on the front surface of the prop. The analogy of pushing air particles behind the vehicle isn't really how the aerodynamics work...

  6. Ujjwal Singh

    Ujjwal Singh

    Prije 45 minuta

    I actually understand how it works but not in terms of energy conservation

    • Ujjwal Singh

      Ujjwal Singh

      Prije 25 minuta

      @eyytee ya , but how

    • eyytee

      eyytee

      Prije 33 minuta

      The wind loses energy. The car gains it.

  7. Roy Hsieh

    Roy Hsieh

    Prije sat

    everyone gangsta until the prop starts shaking

  8. Francisco Garcia

    Francisco Garcia

    Prije sat

    I think it’s possible to drive a vehicle faster than the speed if the down wind, it’s called: a car.

  9. Eunice Oneill

    Eunice Oneill

    Prije 2 sati

    The noiseless run causally found because line notablely disarm towards a sordid mind. obnoxious, garrulous goldfish

  10. Eloy Cristy

    Eloy Cristy

    Prije 2 sati

    The elite kick postmeiotically coach because commission pathophysiologically depend anenst a cheerful tablecloth. abnormal, dear column

  11. Nick Nomine

    Nick Nomine

    Prije 2 sati

    Net positive seems to be the nature of this universe.

  12. Javaughan Nunn

    Javaughan Nunn

    Prije 2 sati

    Turbine?

  13. Andy

    Andy

    Prije 2 sati

    if we can use light as the resource, we can easily travel faster than the speed of light 😂! when someone travel same as speed of light, his/her time will stop! which means time can be manipulated! even though the pilot doesn't feel the change of time because the pilot's time had stopped when he reach the speed of light, but we can still expect to see the pilot come back after million of years later(for the pilot, it just feels like 1 second passed)! and the main problem is, anyone else who didn't travel as fast as speed of light would be dead within 100 year... so only something that can live forever is able to carry out this time travel experiment. therefore, only A.I. is the best participant for inventing the time travel machine 😂

  14. tapas panigrahi

    tapas panigrahi

    Prije 3 sati

    Look at the sail size. That much force can make this light cart faster than the air it's harvesting energy from. Obviously it can't fly lol. That will break the laws of physics.

  15. Mr. Volinski

    Mr. Volinski

    Prije 3 sati

    I wonder how many people figured out that this isn't about transportation but energy generation.

  16. Smokeless Chimney

    Smokeless Chimney

    Prije 3 sati

    We thought the demonstration was well done and provided adequate detail to form an opinion.

  17. Forexmakeit Or break it

    Forexmakeit Or break it

    Prije 3 sati

    warp drive hints here.

  18. alex b

    alex b

    Prije 4 sati

    For me it made it a bit easier to understand how this is possible by knowing how turbines in a hydroelectric power plant are designed. The blades of those are most efficient when they aren't straight but have a w shape. This way looking from the point of the blade itself you push yourself forward by pushing the water back. But looking globally the water won't be reflected against the stream but loose all movement relative to the surroundings. With a flat blade design the water will continue flowing in the direction of the stream and thus still having some energy left. The turbines are most efficient, if the water doesn't move anymore (and just drops straight down because of gravity). With this vehicle it's very similar. As the driver you get pushed by the wind an "deflect" it back again. But looking from the outside you'll see the wind behind the vehicle still moving in the same direction. It will be the fastest and most efficient when the wind pushed back by the prop will be stationary relativ to ground.

  19. Jade Smith

    Jade Smith

    Prije 4 sati

    There's a difference between a sail and a propeller that gives thrust 🤦

  20. Jesse Groves

    Jesse Groves

    Prije 4 sati

    Would be good if someone made a 3d printable model so that people can test it themselves on a treadmill

  21. BloodBlight

    BloodBlight

    Prije 4 sati

    Dude @14:46 in the background looks like @Cody'sLab!

  22. Nudedragon

    Nudedragon

    Prije 4 sati

    While I see the confusion, everyone who's arguing that this is physically impossible even after seeing it done are embarrassing. This vehicle is a demonstration of one of the most fundamental aspects of engineering and science: the laws of physics are a guide not a wall. When you visualized the propellers as sail boats on a cylinder, that helped it click for me. These gentlemen did not violate the conservation of energy, they merely found a way to draw more energy from the wind even after getting up to speed, which is not a violation, but does require some imagination. The sail and windmill are the most basic possible wind technologies, it shouldn't surprise us that there are ways to do more than simply allowing wind to carry us along with it.

  23. Craig Vaughn

    Craig Vaughn

    Prije 6 sati

    How well would this work using the Solar Winds for propulsion? Could a spacecraft use this same principle to travel the inner solar system? Slowing down would be the big issue.

  24. 남알남NamRNam

    남알남NamRNam

    Prije 6 sati

    Okay I still don't get it because... The rotation of the wheel powers the fan, and the fan pushes the wind powers the wheel to rotate, where exactly do we get the power? Even if we are going faster than the wind, the fan is relatively pushing the air and that gives us force, can we accelerate infinitely if the aerodynamic of the car is ideal?? I'm not saying I don't believe the result, I just can't comprehend the situation. Can anyone help me?

    • Rick Cavallaro

      Rick Cavallaro

      Prije 4 sati

      The energy comes from the wind. We leave a wake of slowed-wind that we've robbed of some of it's energy.

  25. X “Chartre” X

    X “Chartre” X

    Prije 7 sati

    12:01 ONEWHEEL! Trrrue happiness.

  26. Danielle Moore

    Danielle Moore

    Prije 7 sati

    The absurd person biochemically last because wheel routinely depend regarding a new jennifer. tidy, squeamish quilt

  27. DAKOTA56777

    DAKOTA56777

    Prije 7 sati

    Now make one to a better quality and see how fast it can go without worrying about that horrible prop balance to shake it to bits.

  28. Imran Qureshi

    Imran Qureshi

    Prije 7 sati

    Wait why is this controversial? The laws of physics apply for force not for velocity ... As windspeed decreases the stored energy should keep the vehicle running . This is basically like a flywheel with the energy stored in the blades momentum

    • Rick Cavallaro

      Rick Cavallaro

      Prije 4 sati

      We have no way of using stored energy. We had to demonstrate that to the North American Land Sailing Association when making the record runs.

  29. Beth Cannon

    Beth Cannon

    Prije 7 sati

    I disagree with your explanation. From what I’ve seen of the diagrams the real way it moves faster than the wind is through optimization of the Coanda effect.

    • John Borton

      John Borton

      Prije 7 sati

      Then you're reading the diagrams wrong or whoever made the diagrams is pulling your chain.

  30. Jure Z

    Jure Z

    Prije 8 sati

    close to 38K comments now, and this comment of mine may be a droplet lost in the sea. My thinking goes like this: The propeller spins always in the same direction. But has variable pitch, even reversible pitch. The vehicle starts with 0 ground velocity, and accelerates downwind pushed by the propeller acting as a sail. At a point having reached enough ground speed, and the propeller producing almost 0 thrust , the propeller pitch increases ( the rotation is not reversed ) , now the wheels drive the propeller , which pushes the vehicle forward as described.

  31. Victor Nunes

    Victor Nunes

    Prije 8 sati

    Awesome!

  32. don brink

    don brink

    Prije 8 sati

    the props arent absorbing the energy first. the props are pushing and condensing the incoming air from behind and then it becomes absorbed as the air incoming is pushing on the air the props force backwards. it creates a bubble of energy that is then absorbed by the cart. an accumulated pocket of energy that the cart has no other choice but to be thrust away from greats vids.

  33. Gary Bradski

    Gary Bradski

    Prije 8 sati

    Thanks or the explanation, but I never doubted that given energy in one form (pushing motion from the air) that it would be possible to convert the energy to some other form (motion on the ground) that is differently related to the speed of the push. For example, using better material, a wind vehicle twice as big but half the mass should go faster still.

  34. Niyazi Uğur

    Niyazi Uğur

    Prije 8 sati

    Why they didnt rent a wind tunnel? This can definitely be a doctorate thesis

  35. T K

    T K

    Prije 9 sati

    So what i see, the propeller works first as a sail and the force it produces go over the tires and a transmission with a ratio that alows the blades to turn against the wind?! So the the propeller moves against the wind with the force of the wind. Maybe a variable transmission with the pitchcontroll together and all controlled by electronic can be the next step to push this project. And a new vehicle ;-)

  36. Matthew Dresser

    Matthew Dresser

    Prije 9 sati

    This is cool and really interesting, but it's a shame you don't mention that this thing can also sail directly upwind as well (maybe it needs a change of gearing, but this was done with a sailboat many years ago)

  37. Dar “BeastMastre” Dudley

    Dar “BeastMastre” Dudley

    Prije 9 sati

    So, it's like a reverse Alcubierre warp drive. Think about it.

  38. Robot Disgrace

    Robot Disgrace

    Prije 10 sati

    You're really short

    • Rick Cavallaro

      Rick Cavallaro

      Prije 4 sati

      Nope. Derek is over 6' tall. I'm just HUGE.

  39. Jai King

    Jai King

    Prije 10 sati

    I want to drive this. Ill even help design a prop that will gather more wind and project the vortices in such a way that they will increase thrust coming off the tips of the blades, Rather than create mechanical drag. I want to see how fast we can get this vehicle to move under the sheer force of wind. Perhaps there could even be a push-pull method to this that could possibly achieve even higher speeds. Such as 120mph on a 20 knot wind. In theory it should work but without testing this will simply stay an idea in my head as I don't have the funding nor the ability to gain enough capital to design such a craft. Or transport said craft to sites in which it can be tested thoroughly.

  40. bikerdude923

    bikerdude923

    Prije 11 sati

    I enjoy all the comments about how physicists/scientists won't believe anything unless they can see the math for why it works, this may be true for some scientists, but anyone who works in a research lab (like I do) could tell you that many scientists are perfectly willing to say "hell if I know how it works, but let's try and figure it out".

  41. dbr opx

    dbr opx

    Prije 11 sati

    13:38 if you listen closely you can hear everyone vacuum seal themselves to their seats 8.5/10 on my pucker factor

  42. guits

    guits

    Prije 11 sati

    Ahem... Kitesurfing. When you want to go downwind as fast as possible you do kiteloops. It generates more lift by flying the kite forward and since it's turning in circles you can keep it continuous. The kite itself pretty much is a wing itself and since the lift is pointed downwind I'm pretty sure you can go faster than the wind. Pretty sure because I haven't measured it but I think it should work. So basically the sail is moving in a cylindrical path but I'm moving straight down wind.

  43. Ioannis Konstantinidis

    Ioannis Konstantinidis

    Prije 11 sati

    I am not pushing back with this comment, I am just wondering... 1) It looks very easy how the wind can pick the whole thing up and get it to move in the first place. It looks heavy (including the pilot) and it's quite aerodynamic. How does it even start moving? What do you think about the cogwheel that connects the wheels with the propeller? How many rotations of the wheels are required for a full rotation of the propeller? I think that is more important than the whole propeller working like a fan.

  44. serialnumber10 belly flop

    serialnumber10 belly flop

    Prije 11 sati

    If it slows down the air behind the blade then it will equaly accelerate the air in front so it evens out. What i think it does is : energy is stored in the blade as rotation cinetic energy and is given to the cart when terminal speed is reached

  45. Jonathan Jollimore

    Jonathan Jollimore

    Prije 11 sati

    COME ON! Someone give me a rocket car to drive on salt flats!!

  46. Daniel

    Daniel

    Prije 11 sati

    Perpetual motion isn't possible! End of the debate

    • Daniel

      Daniel

      Prije 29 minuta

      @eyytee watch the video again

    • eyytee

      eyytee

      Prije 11 sati

      That wasn't the question tough.

  47. Michele Balsamo

    Michele Balsamo

    Prije 11 sati

    I'm an environmental (but not mechanical or aerospace) engineer, but more of this I'm a very curious person... I saw your interesting video and I would know if it could be possible to have a technical drawing (can you ask to the designer Cavallaro?) of the propeller/fan and in particular of its blades, probably the solution of this "wrangle" (I read that there was some of people that have not agreed with the results of this video) is in it. If the "propeller" is not a real propeller but it works like a fan and so the velocity of the air v* in the rear of the machine is less than the main velocity of the wind V then there will be an overpressure zone in the rear of the machine, overpressure on a surface became a force or thrust... I hope you will have the possibility to answer me (ingmbalsamo"at"gmail"dot"com), and anyway I want to thank you for your interesting videos (this one but more of this the one about the Logistic Map). Best Regards

    • eyytee

      eyytee

      Prije 11 sati

      propeller = fan, it speeds up the air in the cart frame, but slows down the air in the ground frame.

  48. The Story Police

    The Story Police

    Prije 12 sati

    We can make a religion out of this...

  49. Khurshed Fitter

    Khurshed Fitter

    Prije 12 sati

    Americans summed up. They do not know what will stop the vehicle xD

  50. Husain Jawahar

    Husain Jawahar

    Prije 12 sati

    I understood this concept but isn't it seems like perpetual motion. the faster the wheels rotate, faster the prop rotates, and the more air it pushes, and so it goes faster, and so faster the wheels rotate... and so on. this can make it go to infite speed.

  51. Lonsad Dessor

    Lonsad Dessor

    Prije 13 sati

    In front of the propeller, the wind speed is greater than behind the propeller, and it turns out that, according to Bernoulli, the air pressure is less in front of the propeller, and behind it is more, so the machine is driving due to the pressure difference. Or is it wrong?

  52. Dana B

    Dana B

    Prije 13 sati

    So now that we know it can be done, what can we do with it? Propellers on boats?

  53. marc prezeau

    marc prezeau

    Prije 13 sati

    The wind indicator pointing backwards does not mean the vehicle is going faster than the wind

    • eyytee

      eyytee

      Prije 12 sati

      @marc prezeau "such a tiny difference in speed" They went 27.7 mph in a 10 mph wind. And NALSA used precise GPS, not a smartphone. Read the technical NALSA docs,

    • John Borton

      John Borton

      Prije 12 sati

      @marc prezeau Like I said ... you have no idea as to the GPS setup that was used. LOL

    • marc prezeau

      marc prezeau

      Prije 13 sati

      @John Borton Gps are notorious for being meters off on a good day and now they are trying to point out such a tiny difference in speed. That tail pointing back says nothing put a plain sail board beside that contraption and watch as the sail board leaves it in the dust I would argue that that the prop and the gears actually slow it down.

    • John Borton

      John Borton

      Prije 13 sati

      @marc prezeau You have no idea as to the GPS setups that were used ... nor the high end anemometers. :)

    • marc prezeau

      marc prezeau

      Prije 13 sati

      @eyytee using a gps as a speedometer is not very accurate ditto for the walmart anemometer. the wheels spin the prop the gear ratio is just enough to create a bit of turbulence to make the tail point back towards the prop.

  54. Fola Dodo

    Fola Dodo

    Prije 14 sati

    I really want to learn physics but I am afraid I won't understand ;-;

  55. zuikatsu

    zuikatsu

    Prije 14 sati

    Just wanted to say huge props (hah) to the drone operator, beautiful shots from that tiny little thing

  56. Mohesh Gupta

    Mohesh Gupta

    Prije 15 sati

    ok so can we generate infinite energy from it if this all working exactly fine. wouldnt this be the end of energy crisis......

  57. Jessica Evans

    Jessica Evans

    Prije 15 sati

    How is he "Risking his Life To Settle A Physics Debate?" xD this is bot risking your life

  58. Adrian Z.

    Adrian Z.

    Prije 15 sati

    Based on the motion of the blades, they indeed push the air backward. As you explained you should experience a propulsion from this motion, but I also believe you should have a difference in air pressure at the front of the blades, allowing the fan to be sucked forward, and increasing your speed further. I might be wrong, as it is an area of physics that twist my mind a bit…. NOTE: Rick and Neil really need to use 3 or 4 blades to stabilise the fan while it is spinning. Centrifuges spin AT LEAST with 3 arms for that reason 😊 engineers can chose other materials to balance the increase in weight of the overall structure if necessary.

  59. Bob Roberts (Down2TheC)

    Bob Roberts (Down2TheC)

    Prije 15 sati

    Only wind relative to the sail surface is important. Multihull Americas Cup hydrofoil boats are exceeding wind speed down wind. Once on the foils, low drag, high speed, and as you turn down wind(ish) the sail has relative wind toward front despite true wind behind. Crazy to see them going 30kts in 12kts wind.

  60. soiung toiue

    soiung toiue

    Prije 16 sati

    Clowning on physics professors isn't an achievement you get everyday

  61. FlatWorldJomhuriRegime88

    FlatWorldJomhuriRegime88

    Prije 16 sati

    Clearly there’s an electric motor in it

    • soiung toiue

      soiung toiue

      Prije 16 sati

      If they would've did something like this in HS I would've liked physics more 😂

  62. HyShade

    HyShade

    Prije 16 sati

    Tier 2 of this tech tree: FTL travel.

  63. tomehost

    tomehost

    Prije 16 sati

    He lost all the flat earthers at the point he had sailing boats on a cylinder.

  64. な だい

    な だい

    Prije 17 sati

    The auspicious editor bailly fear because knee steadily desert alongside a harmonious deficit. trite, military armchair

  65. Aldien Wannuga

    Aldien Wannuga

    Prije 17 sati

    is there a way my pants blown faster than my fart exit from my butt?

  66. airtadeo

    airtadeo

    Prije 17 sati

    I want to Help. I have an idea to progress the acceleration.

  67. imd12c4advice

    imd12c4advice

    Prije 17 sati

    At 8:30 the simulation shows the wrong propeller rotation for forward travel. And also a backwards propeller to boot.

  68. Ch Lope

    Ch Lope

    Prije 18 sati

    Everyone has misunderstood what is really happening here. This wouldn’t work if the earth was flat but because it is curved once you move off the top peak of the curve it is all down hill. This allows you to keep accelerating until you reach the South Pole. Simple and in line with the laws of physics.

  69. Mirage

    Mirage

    Prije 19 sati

    Well its not quite perpetual motion, cause you pull energy from wind

  70. Cosmic Morning

    Cosmic Morning

    Prije 19 sati

    Could there be a way to apply this to gravity / space travel to go further then the speed of light or is it potatoes and tomatoes?

  71. Chris Carter

    Chris Carter

    Prije 19 sati

    Yesterday I posted an answer on Quora to the question: "Could a sailing boat outrun a balloon?" My Answer was, in general NO, and postulated an unlikely situation in which it could happen. I will now have to Eat My Words and humbly admit that I have seen it with my own eyes. It is not a boat but it IS a wind-powered vehicle. You, Sir, are a genius! (Now to figure out how it works...)

    • Bill Carr

      Bill Carr

      Prije 14 sati

      Check out the latest New Zealand America's Cup boats. These boats regularly out run the wind, just not directly downwind.

  72. Setsura- sama

    Setsura- sama

    Prije 19 sati

    I love your explanations, as they’re just dumbed down enough that mostly everyone understood. Though it’s intellectual enough that the more intelligent people don’t feel patronized. That being said, I thought it was like the one myth busters episode. Where they tested if you walked or ran in the rain. Which one would get you more wet. Where running actually got you more wet. As you’re running into more rain than you would be if you walked. As only so much rain (wind in this case) can impact you in that area. So once you meet the speed of the wind. The same amount is hitting you repeatedly, though if you take the cross wind. You get more as you’re entering a new area for it to impart some energy into.

  73. saket vatsa

    saket vatsa

    Prije 19 sati

    Never do I write YT comments. But this blew mew more than any other video out there. Love your work. It never ceases to amaze me :)

  74. Ankit Kumar

    Ankit Kumar

    Prije 19 sati

    Maybe propeller is on height which make drive faster than the string attached to bottom because wind is faster when the height increases or may be momentum get added up

  75. Nathan

    Nathan

    Prije 20 sati

    I wish I could meet you just because the knowledge I would gain in that short amount of time would be amazing. Thanks so much for this video!

  76. David Woodside (Wiseacre Dave)

    David Woodside (Wiseacre Dave)

    Prije 20 sati

    I thought of a 3-part brain teaser based on the downwind cart. Maybe it's trivial and flawed, but it makes you think about the interactions of the cart with the wind. Mount a cup (spinning) anemometer at the top of the cart. a) When the cart is moving relative to the ground at wind speed, what would the anemometer read? b) When the cart is moving relative to the ground at wind speed, is the true wind (the wind from the atmosphere) still pushing on the anemometer? c) Now place a unidirectional, fixed, pitot tube type anemometer on the cart so it can only measure the true wind. Place a second such anemometer on the cart so it can only measure the relative wind. With the cart moving at wind speed across the ground, what would be the sum of the speeds measured by the two anemometers, ignoring energy losses?

    • David Woodside (Wiseacre Dave)

      David Woodside (Wiseacre Dave)

      Prije 8 sati

      @Joan Charmant I researched anemometers a bit more and realized the pitot tube type can be fixed to point in one direction. That's what I had intended for part c). I modified my post accordingly. The cup type anemometer, used for parts a) and b), can sense wind from any direction. Maybe that changes things. Or not!

    • Joan Charmant

      Joan Charmant

      Prije 9 sati

      a) 0 m/s b) no, the anenometer doesn't feel any wind coming from the back c) I don't think you can place the anemometer on the cart such that it could only measure the true wind since the cart is moving.

  77. J Morris

    J Morris

    Prije 20 sati

    If they would've did something like this in HS I would've liked physics more 😂

  78. Sheldon Custer

    Sheldon Custer

    Prije 20 sati

    Sort of like drafting in motorcycle racing. Another idea would be to consider a shroud for the fan to increase efficiency.

  79. Winston (0090)

    Winston (0090)

    Prije 20 sati

    In theory would it be possible to ride it against the wind?

  80. Kenneth Hoadley

    Kenneth Hoadley

    Prije 20 sati

    I have watched the video and read read lots of these comments - some very instructive. My first thoughts were... this is impossible... can't get something for nothing! Who needs an engine if you can go faster than the wind! Of course it is possible the vehicle has a hidden power source but I'm assuming not. At the start, when the vehicle is a rest, it is blown by the tail wind (say 10kt). The cart and prop are acting as a sail. The drive is disengaged so there is no backward force from the prop to wheels. One comment said why not use a sail! It could be thrown overboard once the cart is moving at a certain speed but I don't like the comparisons to a sail boat. The wind can accelerate the vehicle to a maximum speed of (almost) wind-speed. Then if we engage the prop - this will certainly brake the wheels and thus slow the vehicle. Then wind tries to accelerate the vehicle back up to wind-speed. Meanwhile, the prop is pushing air backwards (say 2kt relative to the prop). So the wind-speed at the prop (relative to the ground) is now 8kt... so the wind can give us 2kt more up to 12kt. Then we are in a positive feedback loop until losses (drag/friction) balance gains. Is this how it works?

  81. Sheldon Custer

    Sheldon Custer

    Prije 21 sat

    They should add variable sails to the sides of the prop tower that can be deployed at the start, then drawn as the vehicle speeds up.

  82. Shrawan Dhawale

    Shrawan Dhawale

    Prije 21 sat

    by the way does he use any fule well if he doent then we have infinte enrgy broooooo

    • J Modified

      J Modified

      Prije 14 sati

      Yeah, sailboats are fake - they all have hidden motors.

  83. Lavonia Lauri

    Lavonia Lauri

    Prije 21 sat

    The squealing consonant arguably inject because mouth secondly wriggle worth a sassy cooking. ordinary, permissible seaplane

  84. Subtle Entity

    Subtle Entity

    Prije 21 sat

    He's got no shades!!

  85. MrRickkramer

    MrRickkramer

    Prije 22 sati

    What’s the theoretical maximum ratio between wind speed and vehicle speed? Is there a way to calculate? Is it 3.14159....?

    • eyytee

      eyytee

      Prije 21 sat

      max_speed = wind_speed / (1 - efficiency)

  86. Tom Grüber

    Tom Grüber

    Prije 22 sati

    what about a transmission?

  87. Jan Klas

    Jan Klas

    Prije 22 sati

    So, you had a nice downhill drive :)

    • John Borton

      John Borton

      Prije 13 sati

      @Jan Klas // "Dear John.. I'd advise you go google on 'emoticons, what do they mean and what are they used for'."// // "Usually people who feel the urge to advice someone, have some kind of authority. Usually. Not always. QED."// I'm glad you finally solved your problem and figured out the futility of your actions. Dumbass.

    • Jan Klas

      Jan Klas

      Prije 16 sati

      @John Borton Usually people who feel the urge to advice someone, have some kind of authority. Usually. Not always. QED. If you were to stupid to understand my remark was a joke (the smiley might have given that away, one would say) you're not going to understand anything. Good luck with that.

    • John Borton

      John Borton

      Prije 20 sati

      @Jan Klas I'd advise you Google the word "context", but given the exchange so far (especially given that a smiley face emoticon doesn't mean sarcastic humor) I doubt you would be capable of learning from it so I'll just give you a pass.

    • Jan Klas

      Jan Klas

      Prije 21 sat

      @John Borton Dear John.. I'd advise you go google on 'emoticons, what do they mean and what are they used for'. You might learn something today.

    • John Borton

      John Borton

      Prije 21 sat

      @Jan Klas I see you have no ability to recognize when your 'sarcastic humor' might get muted beyond recognition by thousands of other criticisms.

  88. Sir Zechs

    Sir Zechs

    Prije 23 sati

    Clowning on physics professors isn't an achievement you get everyday

  89. Marc Verderi

    Marc Verderi

    Prije 23 sati

    I'm getting a non-stop headache since I've seen this video... ;)

  90. Dane Beck

    Dane Beck

    Prije dan

    Demonstrating that they're going faster than the wind by itself isn't enough to prove their theory. For example, they could get up to speed and build momentum, then the wind could slow down without necessarily changing direction, which would result in them going faster than the wind and be consistent with their observations. To truly prove this is working they need to verify that the vehicle is continuing to accelerate while going faster than the wind. How do they know the vehicle wasn't decelerating when the streamer was pointing in the opposite direction?

  91. Annabelle Annabelle

    Annabelle Annabelle

    Prije dan

    The ripe waterfall lastly rot because mine inadvertently spell under a like creek. guarded, mundane algeria

  92. A C

    A C

    Prije dan

    Wacky Races

  93. FofoPads

    FofoPads

    Prije dan

    I am not a physicist, but if you add gearbox, doesn't that make the blades spin even faster for the same push force?

    • Tommy2cats

      Tommy2cats

      Prije 5 sati

      The prop on this is already on a pretty huge gear reduction from the wheels. Gearing it up so that the prop spins faster would require more torque at the wheels.

  94. Katherine Montgomery

    Katherine Montgomery

    Prije dan

    The shaggy position relatively multiply because message happily question in a stiff airplane. lonely, demonic archer

  95. InfoRazor

    InfoRazor

    Prije dan

    I would like to suggest a different explaination. Imagine a different car. In which, large turbine is generating electricity from wind power. This electricity is charging an electric battary. And when the driver descides to move, the energy is activating an electric motor, that pushes the vehicle faster than the wind that charged it. This is trivial. I suggest that the vehicle in the video may not have a battery yet does have a way to store wind power. It does it by keeping the energy in the turbine rotation. The way i consider it goes like this: 1) the vehicle is slowly pushed by the wind. Much of the energy is used to "charge" up the turbine. 2) at some point the vehicle gets to wind speed. However at this point the rotation battary is fully charged and its energy is used to push the vehicle forward. 3) since the wind speed is constant, the extra energy from the turbine rotation would push the vehicle above wind speed. Am I wrong?

    • Rick Cavallaro

      Rick Cavallaro

      Prije dan

      >> Am I wrong? Yes. For our record run in 2010 we had to demonstrate that we could not benefit from stored energy.

  96. Matt Brewer

    Matt Brewer

    Prije dan

    8:05 oh god dont give the flat earth guys any ideas

  97. Johnny Thousand

    Johnny Thousand

    Prije dan

    TLD;DR Derek went into the desert and broke wind

  98. Steve Brady

    Steve Brady

    Prije dan

    This broke my brain. But then it healed stronger and better than before!

    • 12ken

      12ken

      Prije 13 sati

      No pain no gain!

  99. Senor Misterioso

    Senor Misterioso

    Prije dan

    Pretty straightforward example of mechanical advantage. The significant mass of the air moving against the vanes of the impeller combined with the gearing of the cart allows for transfer of the kinetic energy of the moving air (wind) to be translated into a low mass vehicle that is easily effected by this acceleration. Once the mass of the vehicle increases, the demand required of the wind to accelerate the vehicle even with mechanical advantage will be too great outside of gale force winds. Will this vehicle accelerate forever? Of course not. It's merely a product of the force of the wind times the mechanical advantage of the machine minus the resistance of the wheels and the drag of the air. Why is this confusing? Ill put $10k on it.

    • Adam Hulu

      Adam Hulu

      Prije dan

      Your explanation sounds more like a wind powered tractor pull when you talk of mechanical advantage. To really understand what is going on, you would get closer to the main idea by comparing it to an ice skater propelling forward by alternately pushing apart then pulling in their legs.

  100. Only 1%

    Only 1%

    Prije dan

    Better than mythbusters

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