Audio illusions show us that hearing is about more than just sensing frequency. Which ones trick you every time? Head to https://brilliant.org/veritasium to start your free 30-day trial and get 20% off an annual premium subscription.

If you’re looking for a molecular modeling kit, try Snatoms, a kit I invented where the atoms snap together magnetically. https://snatoms.com/

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A big thank you to Titus Grenyer over at Pep Organ for showing us around the Sydney Town Hall Organ, to Dr. Diana Deutsch for providing her illusions and insight into the field, to Casey Connor for advice on building sound illusions, and to Dr. Michael Bach for providing the motion-bounce illusion.

Pep organ: https://ve42.co/peporgan
Casey Connor’s Psychoacoustics: https://ve42.co/CaseyConnor

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References: https://ve42.co/AudioIllusionsRefs

Images & Video:

Aircraft Detection before radar, 1917-1940 - https://ve42.co/DetectionBeforeRadar
Women’s Auxiliary Air Force operator Denise Miley - https://ve42.co/ChainHomeRadar
Daventry Experiment Van, operated by “Jock” Herd - https://ve42.co/ChainHome
Perfect fifth - https://ve42.co/PerfectFifth
Denge acoustic mirrors - The original uploader was Jksolomon at English Wikipedia. - https://ve42.co/DengeSoundMirror
Denge sound mirrors | Sound Mirrors https://ve42.co/SoundMirrorsDenge
Mayer telescope in 1880, US patent number 224199. NAE Website - Acoustic Source Localization Techniques and Their Applications https://ve42.co/AcousticSoundL....ocalizationTechnique
Professor Mayer’s Topophone - https://ve42.co/Topophone
AR_Speaker_v12 - Download Free 3D model by steveMarketscale [6ca6a0a] - Sketchfab https://ve42.co/ARSpeaker
Ear Phenotypes https://ve42.co/Earhenotypes

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Special thanks to our Patreon supporters:

Adam Foreman, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Bill Linder, Blake Byers, Bruce, Burt Humburg, Dave Kircher, David Johnston, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, I. H., John H. Austin, Jr., john kiehl, Josh Hibschman, Juan Benet, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Matthias Wrobel, Meekay, meg noah, Michael Krugman, Orlando Bassotto, Paul Peijzel, Richard Sundvall, TTST, Tj Steyn, Ubiquity Ventures, wolfee

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Directed by Sulli Yost and Derek Muller
Hosted by Derek Muller
Written by Sulli Yost and Derek Muller
Edited by Jack Saxon and Peter Nelson
Animated by Fabio Albertelli, David Szakaly, and Ivy Tello
Illustrations by Jakub Misiek
Filmed by Derek Muller
Produced by Sulli Yost, Derek Muller, Rob Beasley Spence, Emily Lazard, Tori Brittain, Emily Zhang, Petr Lebedev, Gregor Čavlović, and Gabe Strong

Thumbnail contributions by Peter Sheppard and Ren Hurley

Additional video/photos supplied by Getty Images, Storyblocks, and Envato

Music from GarageBand, Virtual Piano, and Epidemic Sound

I bought 10,000 shade balls and tried to swim in them. They appear to act like a non-Newtonian fluid: rigid under high shear stress, but they flow like a liquid under low shear.
All the signed shade balls have now been mailed out - thanks for your support!

Receiving a shade ball:
1. Support Veritasium on any Patreon tier and enter your address https://ve42.co/patreon
2. In about a month I will send out signed shade balls
3. I will cover all shipping costs but if things get really crazy I will prioritize existing Patreon supporters and higher tiers

My sense was that swimming in shade balls would be difficult but still doable. This was roughly true for the single layer of shade balls. The shade balls slide past each other so they act like a liquid, albeit a viscous one owing to their significant inertia. It's much more intense exercise and it's also annoying to be bombarded with shade balls on all sides of your body, particularly your head. With multi-layer shade balls (as exists on much of LA reservoir) things get significantly more difficult. The balls bunch together and when you try to move through them quickly, they become more rigid, providing significant resistance to motion. This has the benefit that you can lie on them and as long as they stay trapped under you, you can float on them. But a little bit of motion causes them to move around and you sink through quickly.

Special thanks to our Patreon supporters! Join this community to help us keep our videos free, forever:
https://ve42.co/PatreonDEB

Huge thanks to:
Jordan Schnabel and Cristian Carretero for filming and swimming and providing lifeguard services.
Raquel Nuno for filming and putting up with me.

Music from https://epidemicsound.com "Dubstep Mammoth 2" "Finally Here (Instrumental)" "The Last Arrival" "Sundown Love (Instrumental)"

In Queenstown, New Zealand, I jumped off the Kawarau Bridge - the site of the first bungy jump. It was a thrilling experience, preceded by a terrifying, gut-wrenching half hour wait. All in all an awesome adventure, even if the woman fitting my harness didn't know the first thing about the acceleration of free-falling bodies.

Uranium is a unique element, used in research, medicine, space travel, and of course weapons.
Not broadcast in your country? Contact your local broadcaster and/or email www.genepoolproductions.com

Documentary Dates:
US: PBS, July 28 & 29 @ 10pm ET / 9pm Central
France & Germany: ZDF/arte July 31 @ 10pm
Australia: SBS, August 6, 13, 20 @ 8:30pm EST

If you're wondering where the title comes from...
“A number of ingenious experiments were devised to test the speed of the fission reaction, and the limit was pushed. But even so, I thought it would be very nice to go one step nearer to a real atomic explosion. Dick Feynman, who was present, started to chuckle and to say that this is just like tickling the tail of a sleeping dragon.”
Professor Otto R Frisch, January 1969 Physicist, the Manhattan Project.

The robots of our future may look nothing like humans at all. Head to https://brilliant.org/veritasium to start your free 30-day trial and get 20% off an annual premium subscription.

Huge thanks to Dr. Elliot Hawkes for giving us the updates on his robots, and for showing them to us over the years!

Our videos in this supercut:
https://www.youtube.com/watch?v=qevIIQHrJZg
https://www.youtube.com/watch?v=daaDuC1kbds
https://www.youtube.com/watch?v=ZMQbHMgK2rw
https://www.youtube.com/watch?v=97t7Xj_iBv0
https://www.youtube.com/watch?v=058hRtaCWC0

0:00 - Intro
2:04 - Unstoppable Vine Robot
15:13 - Update on Vine Robot!
20:24 - Highest Jumping Robot
32:15 - Update on the Jumper!
38:26 - Micromouse Competition
1:02:15 - Benefit of non-humanoid robots
1:02:48 - Brilliant
1:04:24 - Bendy Machines
1:16:26 - Soft Robots
1:25:55 - Conclusion

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Special thanks to our Patreon supporters! Join the community to help us keep our videos free, forever: https://ve42.co/PatreonDE

Adam Foreman, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Bill Linder, Blake Byers, Bruce, Burt Humburg, Dave Kircher, David Johnston, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, I. H., John H. Austin, Jr., john kiehl, Josh Hibschman, Juan Benet, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Matthias Wrobel, Meekay, meg noah, Michael Krugman, Orlando Bassotto, Paul Peijzel, Richard Sundvall, Tj Steyn, TTST, Ubiquity Ventures, wolfee, and Yar

If you’re looking for a molecular modeling kit, try Snatoms, a kit I invented where the atoms snap together magnetically - https://ve42.co/SnatomsV

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Images & Video:
All New Atlas via Boston Dynamics on YouTube - https://ve42.co/NewAtlas
Farewell to HD Atlas via Boston Dynamics on YouTube - https://ve42.co/HDAtlas
C-3PO via Cinemax on YouTube - https://ve42.co/C3PO
I, Robot via Movieclips on YouTube - https://ve42.co/iRobot
I, Robot No via ukery on YouTube - https://ve42.co/iRobotNo
Big Hero 6 via Flick Society on YouTube - https://ve42.co/BH6
Big Hero 6 via 茶茶君 on YouTube - https://ve42.co/2ndBH6
Roomba via iRobot on YouTube - https://ve42.co/Roomba

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Filmed by Derek Muller
Edited by Trenton Oliver and Peter Nelson
Produced by Emily Zhang, Gregor Čavlović, Rob Beasley Spence, and Emily Taylor
Thumbnail contributions by Ignat Berbeci, Ren Hurley, and Peter Sheppard
Additional video/photos supplied by Getty Images
Music from Epidemic Sound

In a zero-g plane I experimented with flames and slinkies with surprising results.
Check out e-penser's video: http://ve42.co/EPzeroG
Check out Physicsgirl's video: http://ve42.co/PGzeroG

Thanks to Novespace: http://ve42.co/novespace

Special thanks to Patreon Supporters:
Tony Fadell, Donal Botkin, Nick Luchsinger, Jeff Straathof, Zach Mueller, Ron Neal, Nathan Hansen

The zero-g plane allows for a lot of experiments to be conducted without the expense of getting equipment into orbit. Apparently 80% of microgravity research can be performed in a zero-gravity plane, which is much cheaper than going to space. The flame from the lighter seemed much lazier in zero-g because without weight there is no buoyant force and therefore no convection. This makes the process of combustion more challenging because it's difficult for oxygen to reach the fuel.

Music from the Epidemic Sound: http://ve42.co/epidemic
"Serene Story 2" "In Orbit 2"

Scientific research has shown that heterosexual males and females find members of the opposite sex more attractive when they wear the colour red. This is a subconscious preference that seems to have some evolutionary basis. We attempted to replicate these findings in Sydney but our methods were much less controlled and the results achieved were not statistically significant.

The atmosphere applies a pressure of about 100 000 N to every square metre on Earth's surface. We take this pressure for granted because we have the same amount of pressure pushing out. But what happens when the pressure of the atmosphere is applied to an object with no outward pressure? It implodes. In spectacular fashion.

Higher: http://bit.ly/blockhigher
Same height: http://bit.ly/SameHeight
Lower: http://bit.ly/BlockLower

Special Thanks to:
Henry (MinutePhysics): http://www.youtube.com/minutephysics
Destin (Smarter Every Day): http://www.youtube.com/smartereveryday
Greg and Mitch (ASAP Science): http://youtube.com/asapscience
Elise Andrew (I F***ing Love Science): http://youtube.com/iflscience

Thanks to everyone at RIT and Dickinson College who helped with the making of this video:
Rochester Institute of Technology
Robert Teese, Katelyn Wilkerson, Andrew Gillie, Andrew Stidwill

Dickinson College
This experiment was the brainchild of David Jackson based on a demo at Princeton.
Priscilla Laws, Catrina Hamilton-Drager, Maxine Willis

High-speed camera support:
Charles Zwemer and Bria Antoine

3D printed rockets save on up front tooling, enable rapid iteration, decrease part count, and facilitate radically new designs. For your chance to win 2 seats on one of the first Virgin Galactic flights to Space and support a great cause, go to https://www.omaze.com/veritasium

Thanks to Tim Ellis and everyone at Relativity Space for the tour!
https://www.relativityspace.com/
https://youtube.com/c/RelativitySpace

Special thanks to Scott Manley for the interview and advising on aerospace engineering.
Check out his channel: https://www.youtube.com/user/szyzyg

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References:
Benson, T. (2021). Rocket Parts. NASA. — https://ve42.co/RocketParts

Boen, B. (2009). Winter Wonder: Rocket Icicles. NASA. — https://ve42.co/EngineIcicles

Hall, N. (2021). Rocket Thrust Equation. NASA. — https://ve42.co/RocketEqn

Benson, T. (2021). Rocket Thrust. NASA. — https://ve42.co/RocketThrust

Regenerative Cooling — https://ve42.co/RegenCooling

How A Gold Bullet Almost Destroyed A Space Shuttle by Scott Manley — https://ve42.co/ManleyEngine

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Special thanks to Patreon supporters: Burt Humburg, Blake Byers, Dumky, Mike Tung, Evgeny Skvortsov, Meekay, Ismail Öncü Usta, 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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Written by Derek Muller, Petr Lebedev, and Emily Zhang
Animation by Mike Radjabov
Filmed by Derek Muller, Raquel Nuno, Trenton Oliver, and Emily Zhang
Edited by Trenton Oliver
SFX by Shaun Clifford
Additional video supplied by Getty Images & Pond5
Produced by Derek Muller, Petr Lebedev, and Emily Zhang

Scientists have recently discovered nanodiamonds in the flames of ordinary candles. They are produced at a rate of about 1.5 million per second. Unfortunately they are also burned up at this rate and released into the atmosphere as carbon dioxide. Still this finding may prove useful in the ongoing search for economical ways to produce diamonds.

Vitamins are 13 molecules essential for life that our bodies can't make themselves.
Watch Vitamania here: https://ve42.co/vita

Now available worldwide, except France and Germany where it will be broadcast on ARTE soon. Subscribe on the Vitamania website for updates.

Use #vitamania to join the conversation on Twitter and Facebook.

Vitamania is a Genepool Productions feature documentary for SBS Australia, CuriosityStream, and ARTE France. Principal production investment from Screen Australia, in association with Film Victoria.

This is a #robot that walks, flies, #skateboards, #slacklines, and might do much more one day. A portion of this video was sponsored by Bluehost. Start building a website with Bluehost today. Use my link to receive more than 65% off: https://bluehost.com/track/veritasium #Bluehost #BHcreator

Thanks to Prof. Soon-Jo Chung and everyone at the Aerospace Robotics and Control Lab at Caltech for the tour!
https://aerospacerobotics.caltech.edu/

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References:
Kim, K., Spieler, P., Lupu, S., Ramezani, A., Chung, S. (2021). A bipedal walking robot that can fly, slackline, and skateboard. Science Robotics. — https://www.science.org/doi/10.....1126/scirobotics.ab

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Special thanks to Patreon supporters: S S, Andrew, Benedikt Heinen, Diffbot, Micah Mangione, MJP, Gnare, Dave Kircher, Edward Larsen, Burt Humburg, Blake Byers, Dumky, Evgeny Skvortsov, Meekay, Bill Linder, Paul Peijzel, Mac Malkawi, Michael Schneider, Big Badaboom, Ludovic Robillard, jim buckmaster, Juan Benet, Ruslan Khroma, Robert Blum, Richard Sundvall, Lee Redden, Vincent, Marinus Kuivenhoven, Alfred Wallace, Clayton Greenwell, Michael Krugman, Cy 'kkm' K'Nelson, Sam Lutfi, Ron Neal

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Written by Derek Muller
Filmed by Derek Muller, Trenton Oliver, and Emily Zhang
Edited by Trenton Oliver
Produced by Derek Muller, Petr Lebedev, and Emily Zhang

Standing waves of fire!
Check out Audible: http://bit.ly/AudibleVe
Fysikshow: http://bit.ly/Fysikshow - I'm hosting Michio Kaku in Melbourne ONLY: http://bit.ly/VeKakuTickets

Rubens' Tube is an awesome demo and here we take it to the next level with a two-dimensional 'Pyro Board'. This shows unique standing wave patters of sound in the box.

The pressure variations due to the sound waves affect the flow rate of flammable gas from the holes in the Pyro Board and therefore affect the height and colour of flames. This is interesting for visualizing standing wave patterns and simply awesome to watch when put to music. Thank you to Sune Nielsen and everyone at Aarhus for sharing this demonstration with me! And thanks for having me at your conference.

Music by Kevin MacLeod, www.Incompetech.com "Ice Flow"

This robot has applications to archaeology, space exploration, and search and rescue — with a simple elegant design inspired by a plant. Sign up to Morning Brew for free today: https://ve42.co/mb

Make your own Vine Robot! — https://www.vinerobots.org
Special thanks to A/Prof. Elliot Hawkes, Nicholas Naclerio, Margaret Coad, David Haggerty for appearing in this video and showing off your amazing robots. For more info on vine (and other types of) robots check out https://ve42.co/HawkesLab, and https://ve42.co/CHARM

Research at UCSB supported in part by the National Science Foundation grant 1944816, by an Early Career Faculty grant from NASA’s Space Technology Research Grants Program, and by the Packard Foundation.

B-roll footage of robots from the supplementary materials of (Hawkes et al., 2017) https://ve42.co/VineVideos, and from Stanford University https://ve42.co/StanfordVideo

Additional info on the intubation vine robot here: https://www.wardenchem.com/vine

References: Hawkes, E. W., Blumenschein, L. H., Greer, J. D., & Okamura, A. M. (2017). A soft robot that navigates its environment through growth. Science Robotics, 2(8). — https://ve42.co/Hawkes2017

N. D. Naclerio, A. Karsai, M. Murray-Cooper, Y. Ozkan-Aydin, E. Aydin, D. I. Goldman, E. W. Hawkes, Controlling subterranean forces enables a fast, steerable, burrowing soft robot. Sci. Robot. 6, eabe2922 (2021).
https://robotics.sciencemag.or....g/content/6/55/eabe2

Coad, M. M., Blumenschein, L. H., Cutler, S., Zepeda, J. A. R., Naclerio, N. D., El-Hussieny, H., ... & Okamura, A. M. (2019). Vine robots: Design, teleoperation, and deployment for navigation and exploration. IEEE Robotics & Automation Magazine, 27(3), 120-132. — https://ve42.co/Coad2019

Blumenschein, L. H., Coad, M. M., Haggerty, D. A., Okamura, A. M., & Hawkes, E. W. (2020). Design, modeling, control, and application of everting vine robots. Frontiers in Robotics and AI, 7. — https://ve42.co/Blumenschein2020

Haggerty, D. A., Naclerio, N. D., & Hawkes, E. W. (2019, November). Characterizing environmental interactions for soft growing robots. In 2019 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) (pp. 3335-3342). IEEE. — https://ve42.co/Haggerty2019

Naclerio, N. D., Hubicki, C. M., Aydin, Y. O., Goldman, D. I., & Hawkes, E. W. (2018, October). Soft robotic burrowing device with tip-extension and granular fluidization. In 2018 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) (pp. 5918-5923). IEEE. — https://ve42.co/Naclerio19

Special thanks to Patreon supporters: 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


Edited by Trenton Oliver
Animation by Ivy Tello
Filmed by Derek Muller
Thumbnail by Ignat Berbeci
Music by Jonny Hyman and from Epidemic Sound https://epidemicsound.com

Watch the bullet block experiment first: http://bit.ly/bulletblock
Click for a free audiobook from Audible: http://bit.ly/ZJ5Q6z
An interactive vignette of the bullet block http://ivv.rit.edu/bby/

Can you figure out the spinning disk? http://bit.ly/spinningdisk

Thank you all for the awesome video responses and comments!!

Simulation: http://bit.ly/19SCVnl
Web comic: http://bit.ly/17o8HrR
Wired Blog: http://bit.ly/17o9Dwu
Science Blogs: http://bit.ly/17o9au3
Scientific American: http://bit.ly/19SDoWC
Le's Blog: http://bit.ly/18q1m8a

Video responses from which I borrowed:
http://www.youtube.com/watch?v=hup-l4_Qt_U
http://www.youtube.com/watch?v=uwZ1Mhy0BS0
http://www.youtube.com/watch?v=SgylTbknFdM

Thanks to everyone at RIT and Dickinson College who helped with the making of this video:
Rochester Institute of Technology
Robert Teese, Katelyn Wilkerson, Andrew Gillie, Andrew Stidwill

Dickinson College
This experiment was the brainchild of David Jackson based on a demo at Princeton.
Priscilla Laws, Catrina Hamilton-Drager, Maxine Willis

High-speed camera support:
Charles Zwemer and Bria Antoine

Music: Temper Trap "Love Lost (Instrumental)" and Lights & Motion "Epilogue" licensed from CueSongs.com

Veritasium second channel: http://bit.ly/2Veritasium
Rodney Fox Shark Attack Story: http://bit.ly/1frAwlI
Check out Audible: http://bit.ly/AudibleVe

For this video I went off the coast of South Australia to an island frequented by great white sharks. Here they hunt seals and fish. I've never been scuba diving before but I got into a cage and filmed the sharks under water. It was an incredible experience. Then we came back on the surface to tag the sharks.

Grant Thompson - the King of Random - teaches me how to start a fire with a Sandwich bag. And we tried to melt glass in my backyard: https://goo.gl/zb0uE0
Check out his channel: http://ve42.co/KoR

The intensity of sunlight on Earth is about 1300 Watts per square meter. When you focus the sun's rays using a magnifying glass (or in this case sphere of water) you can increase the intensity roughly ten thousand fold. This increases the temperature of wood to its autoignition point starting the reaction with oxygen in the atmosphere. By protecting the hot embers and adding more energy and fuel, you can get these hot coals to start a roaring fire.

Special thanks to Patreon Supporters:
Tony Fadell, Donal Botkin, Jeff Straathof, Zach Mueller, Ron Neal, Nathan Hansen

Support Veritasium on Patreon: http://ve42.co/patreon

Thank you to Rodney Fox for sharing his story. He was attacked by a shark 50 years ago - Dec. 8 1963. If you're interested in his book or in going shark cage diving in South Australia, check out: http://bit.ly/rodneyfox

This was a pretty extraordinary experience - thanks to NASA for inviting me! The Atlas V 541 rocket took off carrying the Perseverance rover and Ingenuity the Mars helicopter at 7:50 am July 30, 2020. They should arrive in about seven months on February 18, 2021

Thumbnail by Fictionalhead https://www.youtube.com/fictionalhead