The truth, with photons.
I hope I've articulated everything clearly in this video. If not, I'll clarify in comments. Thanks to everyone who appears in this video and thanks to everyone who watches this video!

Veritasium is of course a combination of the latin 'veritas' meaning truth, and the common element ending 'ium'. I guess this is my version of the 'draw my life' craze that rolled through YouTube many years ago. Except I wanted to tell my story with the actual moments, the photons, the stored magnetic states. There's something about that which is so important to me (because I think the alternative involves fooling yourself) which is why I'm so fascinated by film and video.

One of my inspirations for the name Veritasium came from the end of the poem Ode on a Grecian Urn by John Keats, in which he writes:
"Beauty is truth, truth beauty,—that is all
Ye know on earth, and all ye need to know."

Special thanks to Patreon supporters:
Tony Fadell, Donal Botkin, Michael Krugman, Jeff Straathof, Zach Mueller, Ron Neal, Nathan Hansen, Yildiz Kabaran,
Terrance Snow, Stan Presolski

Music from http://epidemicsound.com
Magnified X1 - Gunnar Johnsen
Fluorescent Lights - Martin Gauffin
Dissolving Patterns - Ebb & Flod
Luna - Ebb & Flod

Additional music by Kevin MacLeod: http://incompetech.com
Sneaky Snitch

How an unlikely physics paradox controls these counterintuitive structures. Sponsored by Incogni - Use code veritasium at https://incogni.com/veritasium to get an exclusive 60% off.

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

Sign up to the Veritasium newsletter for weekly science updates - https://ve42.co/Newsletter

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A huge thank you to Paul Ducarme and Bas Overvelde at AMOLF for showing us around.
Check out their research on counter-snapping structures here - https://ve42.co/CounterSnapping

For more on Braess’s Paradox, check out these great videos by Up and Atom (https://youtu.be/cALezV_Fwi0) and Steve Mould (https://www.youtube.com/watch?v=Cg73j3QYRJc)

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0:00 What happens if you cut this rope?
1:41 The Spring Paradox
4:59 New York’s Perplexing Discovery
6:29 Road Networks and Traffic Flow
8:40 Braess’s Paradox
14:29 Snapping
17:16 This object shrinks when you stretch it

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References:

Ducarme, P., Weber, B., Hecke, M. van, & Johannes. (2025). Exotic mechanical properties enabled by countersnapping instabilities. Proceedings of the National Academy of Sciences - https://ve42.co/CounterSnapping
Braess's Paradox via Wikipedia - https://ve42.co/BraessWiki
Braess, D., Nagurney, A., & Wakolbinger, T. (2005). On a Paradox of Traffic Planning. Transportation Science - https://ve42.co/Braess2005
Schäfer, B., Pesch, T., Manik, D., Gollenstede, J., Lin, G., Beck, H.-P., … Timme, M. (2022). Understanding Braess’ Paradox in power grids. Nature Communications - https://ve42.co/Schafer2022
Kolata, G. (1990). What if They Closed 42d Street and Nobody Noticed? New York Times - https://ve42.co/Kolata1990
Youn, H., Gastner, M. T., & Jeong, H. (2008). Price of Anarchy in Transportation Networks: Efficiency and Optimality Control. Physical Review Letters - https://ve42.co/Youn2008
Nicolaou, Z. G., & Motter, A. E. (2012). Mechanical metamaterials with negative compressibility transitions. Nature Materials - https://ve42.co/Nicolaou2012
Counter-Snapping replication package - https://ve42.co/CSPackage

Images & Video:

Earth Day Festivities via VHS Music Rarities - https://www.youtube.com/watch?v=0awPgHjn2nY
Earth Day Speeches - https://www.youtube.com/watch?v=RMDI3kXpeQ8
1990s New York via NYC Nostalgia - https://www.youtube.com/watch?v=0YaFxTw0VqM
42nd Street Closure via Trainluvr - https://www.youtube.com/watch?v=gELde63Fzio
42nd Street Traffic Operator - https://ve42.co/NYCTraffic
Dietrich Braess via opc.mfo.de - https://ve42.co/BraessOPC
Dietrich Braess via Wikipedia - https://ve42.co/BraessWikiPic
Belt Buckle via Mingda Hardware - https://ve42.co/BeltBuckle

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Special thanks to our Patreon supporters:
Adam Foreman, Albert Wenger, Alex Porter, Alexander Tamas, Anton Ragin, armedtoe, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Charles Ian Norman Venn, Dave Kircher, David Johnston, David Tseng, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, Jeromy Johnson, Jon Jamison, JT, Juan Benet, Keith England, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Matthias Wrobel, Meekay, meg noah, Michael Krugman, Orlando Bassotto, Paul Peijzel, Richard Sundvall, Robert Oliveira, Sam Lutfi, Tj Steyn, TTST, Ubiquity Ventures, and wolfee

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Writers: Gregor Čavlović & Derek Muller
Producer & Director: Gregor Čavlović
Editors: James Stuart & Trenton Oliver
Camera Operators: Sander Mook, Dylan Meanwell, Fabio Albertelli, Casper Mebius & Gregor Čavlović
Animator: Fabio Albertelli
Illustrator: Jakub Misiek
Additional Editor: Peter Nelson & James Horsley
Researchers: Darius Garewal & Gabe Strong
Thumbnail Designers: Ren Hurley & Ben Powell
Production Team: Rob Beasley Spence, Tori Brittain & Matthew Cavanagh
Executive Producers: Derek Muller & Casper Mebius

Additional video/photos supplied by Getty Images, Pond5.
Music from Epidemic Sound

Even some physics professors 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 https://www.kiwico.com/Veritasium50

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

Gene Nagata made the shoot possible. If you’re a video nerd like me, check out his channel, Potato Jet: https://www.youtube.com/c/PotatoJet/featured.

Xyla Foxlin for made the model cart used in this video. Xyla builds amazing things like rockets and canoes, check it out! https://www.youtube.com/c/xylafoxlin/

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

Gaunaa, M., Øye, S., & 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 Ivy Tello
Filmed by Gene Nagata, Derek Muller, Trenton Oliver, AJ Fillo and Emily Zhang
Edited by Trenton Oliver
Music from Epidemic Sound https://epidemicsound.com
Additional video supplied by Getty Images
Produced by AJ Fillo

NASA have made a wheel capable of withstanding tough Martian terrain, but just how indestructible is it? Head to https://hensonshaving.com/veritasium and enter code 'Veritasium' for 100 free blades with the purchase of a razor. Make sure to add both the razor and the blades to your cart for the code to take effect.

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A huge thanks to everyone at NASA Glenn Research Center for having us at the SLOPE Lab, showing their work on this indestructible tire, and helping with the science and animation.
A huge thanks to everyone at Smart Tire Co for showing us around their facility, teaching us about nitinol, and letting us flatten their tires.

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References:

Steel Rod Footage - https://ve42.co/SteelRod

H. Föll. 8.4.1 - Martensite. University of Kiel, Faculty of Engineering - https://ve42.co/Foell

Bhattacharya, K. (1998). Theory of martensitic microstructure and the shape-memory effect - https://ve42.co/Bhattacharya1998

Bhattacharya, K. (2003). Microstructure of martensite: why it forms and how it gives rise to the shape-memory effect (Vol. 2). Oxford University Press. - https://ve42.co/MartensiteBook

Shaw, J. A. (2008). Tips and tricks for characterizing shape memory alloy wire: part 1—differential scanning calorimetry and basic phenomena. Experimental Techniques - https://ve42.co/Shaw2008

Buehler, W. J., Gilfrich, J. V., & Wiley, R. C. (1963). Effect of low‐temperature phase changes on the mechanical properties of alloys near composition TiNi. Journal of applied physics, 34(5), 1475-1477.

Kauffman, G. B., & Mayo, I. (1997). The story of nitinol: the serendipitous discovery of the memory metal and its applications. The chemical educator, 2, 1-21. - https://ve42.co/Kauffman1997

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Special thanks to our Patreon supporters:
Emil Abu Milad, Tj Steyn, meg noah, Bernard McGee, KeyWestr, Amadeo Bee, TTST, Balkrishna Heroor, John H. Austin, Jr., john kiehl, Anton Ragin, Benedikt Heinen, Diffbot, Gnare, Dave Kircher, Burt Humburg, Blake Byers, Evgeny Skvortsov, Meekay, Bill Linder, Paul Peijzel, Josh Hibschman, Mac Malkawi, Juan Benet, Ubiquity Ventures, Richard Sundvall, Lee Redden, Stephen Wilcox, Marinus Kuivenhoven, Michael Krugman, Cy ‘kkm’ K’Nelson, Sam Lutfi.

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Written by Derek Muller, Katie Barnshaw, & Emily Zhang
Edited by Trenton Oliver
Animated by Mike Radjabov & Ivy Tello
Coordinated by Emily Zhang
Filmed by Derek Muller, Emily Zhang & Raquel Nuno
Additional video/photos supplied by Getty Images & Pond5
Music from Epidemic Sound
Produced by Derek Muller, Petr Lebedev, & Emily Zhang
Thumbnail by Ignat Berbeci

Negative Pressure Exists! http://bit.ly/TFilQ8
Vsauce's Space Straw: http://bit.ly/XubIm3
Smarter Every Day's Prince Rupert's Drop: http://bit.ly/10VQBGW
ViHart's Optimal Potatoes: http://bit.ly/14egJoe

Thanks to Questacon for filming! Check out their slow-mo playlist: http://bit.ly/ZoWFGR
Science Alert brings science to your news feed: http://on.fb.me/14ehuxA

Music by Kevin Mcleod (http://incompetech.com): Pale Rider & The Cannery

One scientist caused two environmental disasters and the deaths of millions. A part of this video is sponsored by Wren. Offset your carbon footprint on Wren: ​https://www.wren.co/start/veritasium. For the first 100 people who sign up, I will personally pay for the first month of your subscription!

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

Massive thanks to Prof. Francois Tissot for suggesting we make a video on the topic of isotope geochemistry. Huge thanks to Prof. Bruce Lanphear for consulting with us on lead and cardiovascular diseases. Thanks to Rayner Moss for the help with the fire-piston.

Patterson’s 1995 interview audio courtesy of the Archives, California Institute of Technology.

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Other great resources you should check out:
Bill Bryson has a chapter in his fantastic “A Short History of Nearly Everything”
Radiolab have a wonderful podcast: https://www.wnycstudios.org/podcasts/...
Cosmos: A Spacetime Odyssey has a wonderful episode – S1E7 which does a great job of telling the story of Clair Patterson
A fantastic Mental floss article – https://www.mentalfloss.com/article/9...

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References:

Much of the lead-crime hypothesis data is from Rick Nevin’s work – https://ricknevin.com/

WHO factsheet on lead poisoning – https://www.who.int/news-room/fact-sh...

WHO press release about the end of leaded gasoline https://news.un.org/en/story/2021/08/...

UNICEF report – https://ve42.co/UNICEF

Needleman, H. (2004). Lead poisoning. Annu. Rev. Med., 55, 209-222. https://ve42.co/Needleman1

Needleman, H. L. (1991). Human lead exposure. CRC Press. https://ve42.co/Needleman2

Needleman, H. L. et al. (1979). Deficits in psychologic and classroom performance of children with elevated dentine lead levels. New England journal of medicine, 300(13), 689-695. – https://ve42.co/Needleman3

Needleman, H. L. et al. (1996). Bone lead levels and delinquent behavior. Jama, 275(5), 363-369. https://ve42.co/Needleman4

Kovarik, W. J. (1993). The ethyl controversy: the news media and the public health debate over leaded gasoline, 1924-1926 https://ve42.co/Kovarik2

Edelmann, F. T. (2016). The life and legacy of Thomas Midgley Jr. In Papers and Proceedings of the Royal Society of Tasmania https://ve42.co/Edelmann

More, A. F. et al. (2017). Next‐generation ice core technology reveals true minimum natural levels of lead (Pb) in the atmosphere: Insights from the Black Death. GeoHealth, 1(4), 211-219. https://ve42.co/More1

McFarland, M. J., et al. (2022). PNAS 119(11), e2118631119. https://ve42.co/McFarland

Kovarik, W. (2005). Ethyl-leaded gasoline. International Journal of Occupational and Environmental Health, 11(4), 384-397. https://ve42.co/Kovarik3

Nevin, R. (2007). Understanding international crime trends: the legacy of preschool lead exposure. Environmental research, 104(3), 315-336. – https://ve42.co/Nevin2007

Ericson, J. E., et al. (1979). Skeletal concentrations of lead in ancient Peruvians. New England Journal of Medicine, 300(17), 946-951. – https://ve42.co/Ericson1

Patterson, Claire. The Isotopic Composition of Trace Quantities of Lead and Calcium https://ve42.co/Patterson1

Boutron, C. F., & Patterson, C. C. (1986). Lead concentration changes in Antarctic ice during the Wisconsin/Holocene transition. Nature, 323(6085), 222-225. – https://ve42.co/Boulton1

Patterson, C. (1956). Age of meteorites and the earth. Geochimica et Cosmochimica Acta, 10(4), 230-237. – https://ve42.co/Patterson2

Lanphear, B. P. et al (2018). Low-level lead exposure and mortality in US adults: a population-based cohort study. The Lancet Public Health, 3(4), e177-e184. – https://ve42.co/Lanphear1

Schaule, B. K., & Patterson, C. C. (1981). Lead concentrations in the northeast Pacific: evidence for global anthropogenic perturbations. Earth and Planetary Science Letters, 54(1), 97-116. – https://ve42.co/Schaule1

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Special thanks to Patreon supporters: Inconcision, Kelly Snook, TTST, Ross McCawley, Balkrishna Heroor, Chris LaClair, Avi Yashchin, John H. Austin, Jr., OnlineBookClub.org, Dmitry Kuzmichev, Matthew Gonzalez, Eric Sexton, john kiehl, Anton Ragin, Diffbot, Micah Mangione, MJP, Gnare, Dave Kircher, Burt Humburg, Blake Byers, Dumky, Evgeny Skvortsov, Meekay, Bill Linder, Paul Peijzel, Josh Hibschman, Mac Malkawi, Michael Schneider, jim buckmaster, Juan Benet, Ruslan Khroma, Robert Blum, Richard Sundvall, Lee Redden, Vincent, Stephen Wilcox, Marinus Kuivenhoven, Clayton Greenwell, Michael Krugman, Cy 'kkm' K'Nelson, Sam Lutfi, Ron Neal

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Written by Derek Muller, Petr Lebedev, Chris Stewart, and Katie Barnshaw
Edited by Trenton Oliver
Filmed by Petr Lebedev
Animation by Fabio Albertelli, Jakub Misiek, Ivy Tello, Mike Radjabov, and Caleb Worcester
SFX by Shaun Clifford
Additional video/photos supplied by Getty Images
Music from Epidemic Sound
Produced by Derek Muller, Petr Lebedev, and Emily Zhang

How does Japan prepare for its devastating earthquakes? With this giant simulator. For a free trial to Shopify go to https://www.shopify.com/veritasium.

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

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A massive thank you to everyone at NIED for allowing access to their facility. Massive thanks to Okouchi-san for arranging this shoot.

A huge thank you to Dr. Yohsuke Kawamata for the tour of E-defense and for sharing his deep expertise.

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References:
Nakashima, M., et al. (2018). Experiences, accomplishments, lessons, and challenges of E‐defense. Tests using world's largest shaking table. Japan Architectural Review, 1(1), 4-17. - https://ve42.co/Nakashima
Suganuma, K. (2005). 3-D Full-Scale Earthquake Testing Facility (E-Defense). NISTEP Science & Technology Foresight Center. - https://ve42.co/Suganuma
Ohtani, K., et al. (2004). Construction of E-Defense (3-D full-scale earthquake testing facility). In Thirteenth World Conference on Earthquake Engineering (Vol. 189). - https://ve42.co/Ohtani
Horiuchi, T., et al. (2022). Contributions of E-Defense Shaking Table to Earthquake Engineering and its Future. Journal of Disaster Research, 17(6), 985-999. - https://ve42.co/Horiuchi
Nakamura, I., et al. (2008). E-Defense experiments on full-scale wooden houses. In Proceedings of the 14th World conference on earthquake engineering, Beijing, China (pp. 12-17). - https://ve42.co/Nakamura
Japan: The Next Big Quake. Financial Times. - https://ve42.co/BigQuake


Images & Video:
Kobe earthquake compilation - https://ve42.co/Kobe


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Special thanks to our Patreon supporters:
carrotcypher, Chris Harper, Max Paladino, Balkrishna Heroor, Adam Foreman, Orlando Bassotto, Tj Steyn, meg noah, KeyWestr, TTST, John H. Austin, Jr., john kiehl, Anton Ragin, Diffbot, Gnare, Dave Kircher, Burt Humburg, Blake Byers, Evgeny Skvortsov, Meekay, Bill Linder, Paul Peijzel, Josh Hibschman, Juan Benet, David Johnston, Ubiquity Ventures, Richard Sundvall, Lee Redden, Stephen Wilcox, Marinus Kuivenhoven, Michael Krugman, Sam Lutfi.

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Directed by Will Wood and Petr Lebedev
Written by Will Wood, Petr Lebedev and Derek Muller
Edited by Jack Saxon and Trenton Oliver
Animated by Fabio Albertelli, Ivy Tello, Leigh Williamson, David Szakaly
Filmed by Petr Lebedev, Lui Kimishima and Derek Muller
Produced by Will Wood, Petr Lebedev, Han Evans and Derek Muller
Thumbnail by Ren Hurley

Additional video/photos supplied by Getty Images and NIED (E-defense)
Music from Epidemic Sound

How Thermite turned the clickety-clack of railroads into seamless, silent tracks. Get an exclusive 15% discount on Saily data plans! Use code veritasium at checkout. Download Saily app or go to https://saily.com/veritasium
A massive thank you to everyone at Goldschmidt for making this possible. With special thanks to Dr. Axel Hoeschen, Christof Gassmann and Claudia Koch.

If you want to learn all the details about why we don’t need expansion joints anymore, check out Grady’s excellent video here: youtu.be/zqmOSMAtadc

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

Sign up to the Veritasium newsletter for weekly science updates - https://ve42.co/Newsletter

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00:00 The problem with continuous welded rail
03:33 How to weld two rails together
10:16 Why is rapidly cooled steel brittle?
11:40 Thermite reaction and a see-through mould
16:30 Clean up
19:11 Metallurgy
22:15 How strong is the weld?
24:26 Why don’t the rails buckle?

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References:
Practical Engineering. Why Railroads Don't Need Expansion Joints youtu.be/zqmOSMAtadc
Stress–strain curve In Wikipedia - https://ve42.co/stressstrain
The Efficient Engineer. Understanding Metals via Youtube https://youtu.be/PaGJwOPg2kU
moodlemech. Properties and Grain Structure via Youtube - youtu.be/uG35D_euM-0

Images & Video:
bhadeshi123. Martensitic transformation via Youtube youtu.be/OQ5lVjYssko
Stratford Works In Wikipedia - https://ve42.co/stratford
Electric Tram 1881 In Wikipedia - https://ve42.co/tram
Water Quenched Steel In Wikipedia - https://ve42.co/quench
Synagoge 1922 In Wikipedia - https://ve42.co/synagoge

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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

Alexander Tamas, Autodidactic Studios, Farbod Mansorian, Gnare, Juan Benet, Lee Redden, Meekay, Orlando Bassotto, Paul Peijzel, Richard Sundvall, Sam Lutfi, Ubiquity Ventures, Adam Foreman, Albert Wenger, Anton Ragin, Bertrand Serlet, Blake Byers, Bruce, Dave Kircher, David Johnston, Evgeny Skvortsov, Garrett Mueller, gpoly, Greg Scopel, I. H., KeyWestr, Kyi, Marinus Kuivenhoven, Matthias Wrobel, meg noah, Michael Krugman, Spilmann Reed, Tj Steyn, TTST, wolfee.

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Directed by Derek Muller and Casper Mebius
Written by Derek Muller and Casper Mebius
Edited by Trenton Oliver
Animated by Mike Radjabov, Rokas Vikšraitis and Fabio Albertelli
Filmed by Derek Muller, David Bochmann, Casper Mebius, Luise Dietert, Henning Fischer and Harald Schweiger
Additional research by Geeta Thakur
Produced by Derek Muller, Casper Mebius, Gregor Čavlović, Geeta Thakur, Rob Beasley Spence, Emily Lazard and Tori Brittain
Thumbnail contributions by Peter Sheppard and Ren Hurley
Additional video/photos supplied by Getty Images and Story Blocks
Music from Epidemic Sound

The Event Horizon Telescope Collaboration observed the supermassive black hole at the center of M87, finding the dark central shadow in accordance with General Relativity, further demonstrating the power of this 100 year-old theory.

To understand more about why the shadows look the way they do, check out: https://www.youtube.com/watch?v=zUyH3XhpLTo

I will continue updating this description with more links.

Event Horizon Telescope collaboration: https://ve42.co/EHT

Animations and simulations with English text:
L. R. Weih & L. Rezzolla (Goethe University Frankfurt)
https://youtu.be/jvftAadCFRI

Video of observation of M87 courtesy of:
C. M. Fromm, Y. Mizuno & L. Rezzolla (Goethe University Frankfurt)
https://youtu.be/meOKmzhTcIY

Video of observation of SgrA* courtesy of
C. M. Fromm, Y. Mizuno & L. Rezzolla (Goethe University Frankfurt)
Z. Younsi (University College London)
https://youtu.be/VnsZj9RvhFU

Video of telescopes in the array 2017:
C. M. Fromm & L. Rezzolla (Goethe University Frankfurt)
https://youtu.be/Ame7fzBuFnk

Animations and simulations (no text):
L. R. Weih & L. Rezzolla (Goethe University Frankfurt)
https://youtu.be/XmvpKFSvB7A

Special thanks to Patreon supporters:
Donal Botkin, Michael Krugman, Ron Neal, Stan Presolski, Terrance Shepherd, Penward Rhyme

Scale animation by Maria Raykova

The US Navy has an indoor ocean that can simulate any wave in the world. This video is sponsored by Brilliant. You can get started for free, or the first 200 people to sign up via https://brilliant.org/veritasium get 20% off a yearly subscription.

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

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Thanks to Kelley Stirling and the Naval Surface Warfare Center, Carderock Division for the visit.
Thanks to Miguel Quintero and Capt. Todd E. Hutchison for talking to us about the important work going on in the Maneuvering and Seakeeping Basin.
Thanks to Dr. Georgy Manucharyan at the University of Washington for his help in understanding ocean waves.

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References:

Webb, P. (2017). Introduction to Oceanography. Chapter 10: Waves. Online OER textbook. – https://ve42.co/Webb2017
Stewart, R. (2008). Introduction to Physical Oceanography. – https://ve42.co/Stewart2008
van den Bremer, T. S. & Breivik, Ø. (2018). Stokes drift. Phil. Trans. R. Soc. A. – https://ve42.co/Bremer2017
Monismith, S. (2020). Stokes drift: Theory and experiments. Journal of Fluid Mechanics, 884, F1. – https://ve42.co/Monismith2020
Young, I. R. (1999). Wind Generated Ocean Waves. Elsevier. p. 83. – https://ve42.co/Young1999
Wright, P. Island Physics. 4.2 Formation of Waves – https://ve42.co/IslandPhysics
American Bureau of Shipping. (2016). Guidance Notes on Selecting Design Wave by Long Term Stochastic Method. – https://ve42.co/ABS2016
James, S. & Stull, R. (2019). Wave Characteristics. UBC ATSC 113 - Weather for Sailing, Flying & Snow Sports. – https://ve42.co/James2019
Garrison, T. (2009). Oceanography: An Invitation to Marine Science (7th ed). – https://ve42.co/Garrison2009

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Special thanks to our Patreon supporters:
James Sanger, Louis Lebbos, Elliot Miller, Brian Busbee, Jerome Barakos M.D., Amadeo Bee, TTST, Balkrishna Heroor, Chris LaClair, John H. Austin Jr., OnlineBookClub.org, Matthew Gonzalez, Eric Sexton, John Kiehl, Diffbot, Gnare, Dave Kircher, Burt Humburg, Blake Byers, Evgeny Skvortsov, Meekay, Bill Linder, Paul Peijzel, Josh Hibschman, Mac Malkawi, Mike Schneider, John Bauer, Jim Buckmaster, Juan Benet, Sunil Nagaraj, Richard Sundvall, Lee Redden, Stephen Wilcox, Marinus Kuivenhoven, Michael Krugman, Cy 'kkm' K'Nelson, Sam Lutfi

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Written by Derek Muller & Emily Zhang
Edited by Fabio Albertelli
Animation by Ivy Tello & Mike Radjabov
Filmed by Derek Muller & Emily Zhang
Additional video/photos supplied by Pond5 & Getty Images
Music from Epidemic Sound
Produced by Derek Muller, Petr Lebedev, and Emily Zhang

The title and thumbnail play a huge role in a video's success or failure.
Check out http://kiwico.com/Veritasium50 for 50% off your first month of any subscription!

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Special thanks to Patreon supporters: Alvaro Naranjo, 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
Animation by Ivy Tello
Filmed by Derek Muller and Emily Zhang
Additional video supplied by Getty Images
Produced by Derek Muller, Emily Zhang and Petr Lebedev

If you spin a raw egg and then stop it, it will start spinning again without you having to touch it. A boiled egg, on the other hand, stops and stays stopped. Why is this? Well a raw egg contains a yolk that moves inside the egg independently of the shell. If you stop the shell, the yolk inside continues to move due to its inertia and it therefore gets the egg spinning again.

I always wanted to know why film looked better than video. Moving electronic images have as long a history but were invented for a different purpose. This video was sponsored by B&H Photo: https://www.bhphotovideo.com

Huge thanks to:

Richard Diehl, Video Labguy https://www.youtube.com/user/videolabguy
https://www.labguysworld.com

Branch Education for awesome animations
https://ve42.co/BranchEd

Minutephysics for mechanical TV animations
https://www.youtube.com/minutephysics

Mark Schubin
Engineer and explainer, SMPTE Life Fellow
https://www.smpte.org

This is a video I've long wanted to make, about what makes video look like video and, up until 10 years ago or so, not as appealing as film. I grew up with the two technologies (film and video) in parallel and to me they always seemed like two ways of achieving the same ends: recording and replaying moving images. But their histories are quite distinct. Film was always a way to capture moving images for later replaying. Video started out as a way to transfer images from one place to another instantaneously. This dates back to the first fax machine, mechanical TV, live broadcast tv and ultimately videotapes. This history focuses on the early decades of video and not the more recent switches to chip cameras and solid state storage. Maybe that's a story for another day.

Additional resources and references:

The Dawn of Tape: Transmission Device as Preservation Medium
https://ve42.co/dawnoftape

What Sparked Video Research in 1877? The Overlooked Role of the Siemens Artificial Eye
https://ve42.co/sparkvideo

Video Preservation Website:
http://videopreservation.conservation-us.org

Image Orthicon Tube:
http://interiorcommunicationse....lectrician.tpub.com/

Film vs Digital
https://stephenfollows.com/film-vs-digital/

Eyes of a Generation:
http://eyesofageneration.com

Television in the US:
http://www3.northern.edu/wild/th100/tv.htm

http://www.classictvinfo.com

Music from https://www.epidemicsound.com "Seaweed" "Capture a Picture 1" "Colorful Animation 4"

The biggest chemical cover up in history. PFAS has polluted the entire global water system. Now, potentially dangerous forever chemicals are being found in the entire US population. Go to https://groundnews.com/Ve to get all sides of every story. Subscribe to save 40% off the unlimited Vantage Plan through our link.

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

Sign up to the Veritasium newsletter for weekly science updates - https://ve42.co/Newsletter

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0:00 Killed by Fridges
5:27 Teflon and The Manhattan Project
7:59 Teflon is Tricky
11:37 The Teflon Revolution
13:27 Earl Tennant's Farm
17:34 Inside DuPont
20:28 Fluoride In Drinking Water
25:00 It's bigger than that
29:23 What is PFAS?
35:56 How much PFAS is in Derek’s blood?
37:56 How forever chemicals get into your blood
46:18 Removing PFAS from drinking water
49:30 Can you lower your PFAS levels?

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A huge thank you to Rob Bilott for his time and expertise. Check out his fantastic book: Bilott, R. (2019). Exposure. Simon and Schuster - https://ve42.co/7R

Rob's story also inspired the 2019 film: Dark Waters.

Thank you to Doctor Mike for giving us a medical perspective on PFAS! Check him out at @DoctorMike

Thank you to Henrik Haggeman and the Puraffinity team, as well as Andrew Patterson and Eurofins, for doing the PFAS testing.

Thank you to Leslie Hamilton, Johns Hopkins APL, Alex Conrad, Imperial College London, Jana Avgustini, and Matija Krvavica for their help on the project.

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PFAS Tools:
PFAS Blood Test - https://ve42.co/PFASTest
What's My Exposure? via www-pfas.pfas-exchange.org - https://ve42.co/myexposure
Serum PFAS Calculator via ics.uci.edu - https://ve42.co/pfascalculator
Interactive Map: PFAS Contamination Crisis via www.ewg.org - https://ve42.co/pfasmapinteractive
The Map of Forever Pollution via foreverpollution.eu - https://ve42.co/foreverpollutionmap
Australian PFAS Chemicals Map via pfas.australianmap.net - https://ve42.co/australianpfasmap

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References:

References can be found here - https://ve42.co/PFASReferences

Images & Video:

Image and video references can be found here - https://ve42.co/PFASVisuals

3D Models:

"Low Poly Base Mesh-530 Tri" (https://skfb.ly/onsxE) by Huge_Man
"Blood Vessel" (https://skfb.ly/owHJX) by IMU University
“Generic Factory” (https://skfb.ly/onQpR) by assetfactory
"Lowpoly People + Waldo" (https://skfb.ly/6zqCE) by Loïc Norgeot
PFOA Molecule via PubChem - https://pubchem.ncbi.nlm.nih.g....ov/compound/Perfluor

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Special thanks to our Patreon supporters:
Adam Foreman, Albert Wenger, Alex Porter, Alexander Tamas, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Dave Kircher, David Johnston, David Tseng, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, iRick, Jon Jamison, Juan Benet, Keith England, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Matthias Wrobel, Meekay, meg noah, Michael Krugman, Orlando Bassotto, Paul Peijzel, Richard Sundvall, Sam Lutfi, Samuel White, TTST, Tj Steyn, Ubiquity Ventures, wolfee

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Writers: Gregor Čavlović & Derek Muller
Producer & Director: Gregor Čavlović
Editors: Peter Nelson & Jack Saxon
Camera Operators: Tas Underwood, Emilia Gyles, Gregor Čavlović & Derek Muller
Animators: Andrew Neet, Emma Wright & Fabio Albertelli
Illustrators: Caine Esperanza, Jakub Misiek & Maria Gusakovich
Assistant Editor: James Stuart
Additional Editor: James Horsley
Researchers: Geeta Thakur, Darius Garewal, Gabe Strong & Emilia Gyles
Thumbnail Designers: Ren Hurley & Ben Powell
Production Team: Rob Beasley Spence, Tori Brittain, Casper Mebius, Sulli Yost & Matthew Cavanagh
Executive Producers: Derek Muller & Zoe Heron

Additional video/photos supplied by Getty Images, Pond5.
Music from Epidemic Sound

The logistic map connects fluid convection, neuron firing, the Mandelbrot set and so much more. Fasthosts Techie Test competition is now closed! Learn more about Fasthosts here: https://www.fasthosts.co.uk/veritasium Code for interactives is available below...

Animations, coding, interactives in this video by Jonny Hyman 🙌
Try the code yourself: https://github.com/jonnyhyman/Chaos

References:
James Gleick, Chaos
Steven Strogatz, Nonlinear Dynamics and Chaos

May, R. Simple mathematical models with very complicated dynamics. Nature 261, 459–467 (1976). https://doi.org/10.1038/261459a0

Robert Shaw, The Dripping Faucet as a Model Chaotic System
https://archive.org/details/Sh....awRobertDrippingFauc

Crevier DW, Meister M. Synchronous period-doubling in flicker vision of salamander and man.
J Neurophysiol. 1998 Apr;79(4):1869-78.

Bing Jia, Huaguang Gu, Li Li, Xiaoyan Zhao. Dynamics of period-doubling bifurcation to chaos in the spontaneous neural firing patterns Cogn Neurodyn (2012) 6:89–106 DOI 10.1007/s11571-011-9184-7

A Garfinkel, ML Spano, WL Ditto, JN Weiss. Controlling cardiac chaos
Science 28 Aug 1992: Vol. 257, Issue 5074, pp. 1230-1235 DOI: 10.1126/science.1519060

R. M. May, D. M. G. Wishart, J. Bray and R. L. Smith Chaos and the Dynamics of Biological Populations
Source: Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences, Vol. 413, No. 1844, Dynamical Chaos (Sep. 8, 1987), pp. 27-44

Chialvo, D., Gilmour Jr, R. & Jalife, J. Low dimensional chaos in cardiac tissue. Nature 343, 653–657 (1990). https://doi.org/10.1038/343653a0

Xujun Ye, Kenshi Sakai. A new modified resource budget model for nonlinear dynamics in citrus production. Chaos, Solitons and Fractals 87 (2016) 51–60

Libchaber, A. & Laroche, C. & Fauve, Stephan. (1982). Period doubling cascade in mercury, a quantitative measurement. http://dx.doi.org/10.1051/jphy....slet:019820043070211 43. 10.1051/jphyslet:01982004307021100.

Special thanks to Patreon Supporters:
Alfred Wallace, Arjun Chakroborty, Bryan Baker, DALE HORNE, Donal Botkin, halyoav, James Knight, Jasper Xin, Joar Wandborg, Lee Redden, Lyvann Ferrusca, Michael Krugman, Pindex, Ron Neal, Sam Lutfi, Tige Thorman, Vincent

Special thanks to:
Henry Reich for feedback on earlier versions of this video
Raquel Nuno for enduring many earlier iterations (including parts she filmed that were replaced)
Dianna Cowern for title suggestions and saying earlier versions weren't good
Heather Zinn Brooks for feedback on an earlier version.


Music from:
https://epidemicsound.com "What We Discovered" "A Sound Foundation 1" "Seaweed" "Colored Spirals 4"

https://ve42.co/Artlist "Busy World" "Children of Mystery"

Can you trust your phone? Head to https://brilliant.org/veritasium to start your free 30-day trial and get 20% off an annual premium subscription.

A huge thank you to Linus Sebastian and the team at Linus Tech Tips - check them out at @LinusTechTips

A massive thank you to Alexandre De Oliveira and Karsten Nohl (aka @hackingmatters) for making this demo possible. Karsten has made a great follow-up video on the subject, which you can watch here: https://www.youtube.com/watch?v=miXRoy-5LLo

A special thanks to Crofton Black at Lighthouse Reports, Cathal Mc Daid at Enea, and James Hobson at @hacksmith

00:00 I hacked Linus!
00:59 How Steve Jobs and Steve Wozniak hacked the telephone network
02:22 Early history of the telephone
07:08 The kidnapping of Sheikha Latifa
08:41 How Signalling System No. 7 works
11:03 Why SS7 is vulnerable to hacking
12:15 How hackers gain access to phones
16:17 How I was able to spy on Linus’ phone
18:09 How hackers can intercept text messages
21:04 How your location can be tracked via SS7
29:03 How to protect your phone from hacking

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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, Albert Wenger, 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., Jack Cuprill, John H. Austin, Jr., john kiehl, Juan Benet, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Matthias Wrobel, Meekay, meg noah, Michael Krugman, Orlando Bassotto, Paul Peijzel, Richard Sundvall, Sam Lutfi, Tj Steyn, TTST, Ubiquity Ventures and wolfee

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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References:
Black, C. (2020). Spy companies using Channel Islands to track phones around the world. The Bureau of Investigative Journalism - https://ve42.co/SpyTBIJ
It is dangerously easy to hack the world’s phones via The Economist - https://ve42.co/EconHack
Blake, H. (2023). The Fugitive Princesses of Dubai. The New Yorker - https://ve42.co/DubaiNY
McDaid, C. (2021). How Surveillance Companies Track You Using Mobile Networks. media.ccc.de - https://ve42.co/McDaid2021
Engel, T. (2014). SS7: Locate. Track. Manipulate. media.ccc.de - https://ve42.co/Engel2014
Nohl, K. (2014). Mobile self-defense. media.ccc.de - https://ve42.co/Nohl2014
How Cell Service Actually Works via WendoverProductions - https://ve42.co/CellWendover
How Telephone Phreaking Worked via The 8-Bit Guy - https://ve42.co/8BitGuy
Transmission Lines: Part 1 An Introduction via TheSiGuy - https://ve42.co/TheSiGuy
The Step-By-Step Switch via AT&T Tech Channel - https://ve42.co/SwitchATNT
Hacking Your Phone via 60 Minutes - https://ve42.co/60minHack
Rosenbaum, R. (1971). Secrets of the Little Blue Box. The Esquire Magazine - https://ve42.co/Rosenbaum1971
Black, C. et. al. (2023). Ghost in the network. Lighthouse Reports - https://ve42.co/Black2023
Kerr, D. (2019). The step-by-step telephone switching system. dougkerr.net - https://ve42.co/Kerr2019
Ecall and 2G/3G Network Obsolescence via PFA Plateforme Automobile - https://ve42.co/PFAAuto2021


Images & Video:
All references can be found here: https://ve42.co/PhoneSpyingImageVideo

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Directed by Henry van Dyck
Written by Henry van Dyck
Edited by Laura Mills
Animated by Fabio Albertelli, Ivy Tello, David Szakaly, and Jakub Misiek
Filmed by Derek Muller and Linus Media Group Team
Additional research by Gabe Strong
Produced by Derek Muller, Henry van Dyck, Rob Beasley Spence, Tori Brittain, Emily Lazard, Luke Lewis, Gregor Čavlović, and Emily Zhang
Thumbnail contributions by Ren Hurley and Peter Sheppard

Additional video/photos supplied by Getty Images and Storyblocks
Music from Epidemic Sound

What was the procedure to launch a nuclear missile?
Uranium premieres: July 28 & 29 on PBS at 10pm ET/ 9pm Central
France and Germany: July 31 at 10pm on ZDF/arte
Norway: August 5 & 6 at 21:30 on NRK2
Australia: August 9, 16, 23 at 8:30pm on SBS
Sweden: TBD
Middle East: TBD

For more information on other screenings go to
https://www.facebook.com/uraniumtwistingthedragon
www.genepoolproductions.com

A big thank you to The Titan Missile Museum, Yvonne and Chuck.
http://www.titanmissilemuseum.org/

Space footage courtesy of NASA

A recent survey of scientific literacy in Australia found 30% believe it takes one day for the Earth to go around the sun. This video provides qualitative evidence for the finding from Sydney's Eastern beaches.

An engineer came up with a plan to drop tungsten telephone poles from space - the idea has been seriously considered on multiple occasions, so we tested it. Head to https://brilliant.org/Veritasium to start your free trial. The first 200 will get 20% off Brilliant's annual premium subscription.

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

Massive thanks to Archisand for building such a beautiful sandcastle. https://www.youtube.com/@GregLeBon

Huge thanks to John and Angie Miller for helping us with securing the shooting location and going above and beyond to make this shoot happen – http://highdesertlocations.com/

Thanks to Inland Empire Film Services and the San Bernardino County Film Office for portions of the video shot in the County of San Bernardino.

Massive thanks to Dr David Wright for the interview and providing invaluable guidance during the research for this video.

Here’s a great video about space-based missile defense – https://www.ucsusa.org/resourc....es/space-based-missi

Massive thanks to Adam Savage for being part of this video.

Additional photos from NASA and ESA.

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References:
USAF. (2003). The US Air Force transformation flight plan.

Preston, R., Johnson, D. J., Edwards, S. J., Miller, M. D., & Shipbaugh, C. (2002). Space weapons earth wars. Rand Corporation.

Wright, D., Grego, L., & Gronlund, L. (2005). The physics of space security. A Reference Manual, Cambridge.

DeBlois, B. M., Garwin, R. L., Kemp, R. S., & Marwell, J. C. (2004). Space weapons: crossing the US Rubicon. International Security, 50-84.

Baucom, D. R. (2017). The Rise and Fall of Brilliant Pebbles 1. In United States Military History 1865 to the Present Day (pp. 329-376). Routledge.

Hitchens, T., & Samson, V. (2004). Space-based interceptors: still not a good idea. Georgetown journal of international affairs, 21-29.

National Research Council. (2012). Making sense of ballistic missile defense: An assessment of concepts and systems for US boost-phase missile defense in comparison to other alternatives. National Academies Press.

Borger, J. (2005). Bush likely to back weapons in space. The Guardian, 19.

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Special thanks to: Bernard McGee, James Sanger, Elliot Miller, Brian Busbee, Jerome Barakos M.D., Amadeo Bee, TTST, Balkrishna Heroor, Chris LaClair, John H. Austin Jr., OnlineBookClub.org, Eric Sexton, John Kiehl, Diffbot, Gnare, Dave Kircher, Burt Humburg, Blake Byers, Evgeny Skvortsov, Meekay, Bill Linder, Paul Peijzel, Josh Hibschman, Mac Malkawi, Mike Schneider, John Bauer, Jim Buckmaster, Juan Benet, Sunil Nagaraj, Richard Sundvall, Lee Redden, Stephen Wilcox, Marinus Kuivenhoven, Michael Krugman, Cy 'kkm' K'Nelson, Sam Lutfi

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Written by Petr Lebedev, Derek Muller, and Emily Zhang
Filmed by Trenton Oliver, Derek Muller, Petr Lebedev, Emily Zhang, Raquel Nuno, and Eddie Lopez
Animation by Mike Radjabov, Fabio Albertelli, and Jonny Hyman
Edited by Trenton Oliver
Slow Motion Camera: Shawn Sanders and Anthony Corrales
Sandcastle Timelapse by Greg LeBon and Archisand
Phantom rental from Panny Hire LA
Helicopter Pilots: Rick Shuster and Cliff Fleming
Helicopter Safety Officer: Ryan Hosking
FPV Drone Pilots: Sammie Saing and Josh Ewalt
Production Assistants: Roman Bacvic and Eddie Lopez
Intern: Katie Barnshaw
Additional video/photos supplied by Pond5 and Getty Images
Music from Epidemic Sound
Thumbnail by Ignat Berbeci
Produced by Derek Muller, Petr Lebedev, and Emily Zhang

A basketball and a 5kg medicine ball are dropped simultaneously. Which one hits the ground first? It seems obvious that the heavy one should accelerate at a greater rate and therefore land first because the force pulling it down is greater. But this is forgetting inertia - the tendency of mass to resist changes in motion. Therefore, although the force on the medicine ball is greater, it takes this larger force to accelerate the ball at the same rate as the basketball.