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The Bizarre Behavior of Rotating Bodies, Explained

  • The Bizarre Behavior of Rotating Bodies, Explained


    Spinning objects have strange instabilities known as The Dzhanibekov Effect or Tennis Racket Theorem - this video offers an intuitive explanation.
    Part of this video was sponsored by LastPass, click here to find out more:

    Prof. Terry Tao's Math Overflow Explanation:

    The Twisting Tennis Racket
    Ashbaugh, M.S., Chicone, C.C. & Cushman, R.H. J Dyn Diff Equat (1991) 3: 67.

    Janibekov’s effect and the laws of mechanics
    Petrov, A.G. & Volodin, S.E. Dokl. Phys. (2013) 58: 349.

    Tumbling Asteroids
    Prave et al.

    The Exact Computation of the Free Rigid Body Motion and Its Use in Splitting Methods
    SIAM J. Sci. Comput., 30(4), 2084–2112
    E. Celledoni, F. Fassò, N. Säfström, and A. Zanna

    Animations by Iván Tello and Isaac Frame

    Special thanks to people who discussed this video with me:
    Astronaut Don Pettit
    Henry Reich of MinutePhysics
    Grant Sanderson of 3blue1brown
    Vert Dider (Russian YouTube channel)

    Below is a further discussion by Henry Reich that I think helps summarize why axes 1 and 3 are generally stable while axis 2 is not:

    In general, you might imagine that because the object can rotate in a bunch of different directions, the components of energy and momentum could be free to change while keeping the total momentum constant.

    However, in the case of axis 1, the kinetic energy is the highest possible for a given angular momentum, and in the case of axis 3, the kinetic energy is the lowest possible for a given angular momentum (which can be easily shown from conservation of energy and momentum equations, and is also fairly intuitive from the fact that kinetic energy is proportional to velocity squared, while momentum is proportional to velocity - so in the case of axis 1, the smaller masses will have to be spinning faster for a given momentum, and will thus have more energy, and vice versa for axis 3 where all the masses are spinning: the energy will be lowest). In fact, this is a strict inequality - if the energy is highest possible, there are no other possible combinations of momenta other than L2=L3=0, and vice versa for if the energy is the lowest possible.

    Because of this, in the case of axis 1 the energy is so high that there simply aren't any other possible combinations of angular momentum components L1, L2 and L3 - the object would have to lose energy in order to spin differently. And in the case of axis 3, the energy is so low that there likewise is no way for the object to be rotating other than purely around axis 3 - it would have to gain energy. However, there's no such constraint for axis 2, since the energy is somewhere in between the min and max possible. This, together with the centrifugal effects, means that the components of momentum DO change.

  • Anti-Gravity Wheel?


    Explanation of gyro precession:
    Less Than:
    Equal To:

    Huge thanks to A/Prof Emeritus Rod Cross, Helen Georgiou for filming, Alex Yeung, and Chris Stewart, the University of Sydney Mechanical Engineering shop, Duncan and co. Ralph and the School of Physics.

    In this video I attempt to lift a 19kg (42 lbs) wheel over my head one-handed while it's spinning at a few thousand RPM. This replicates an earlier experiment by Professor Eric Laithwaite. He claimed the wheel was 'light as a feather' and could not be explained by Newton's Laws. I wanted to find out for myself what I really felt like.

    Music By Kevin MacLeod Tempting Secrets

  • Explained: 5 Fun Physics Phenomena


    Explanations for
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    For more on deflecting polar streams with electric fields, see:

    I'm in Hobart for a live show on Friday at UTAS followed by gigs in Sydney and Canberra next weekend.

  • Spinning Black Holes


    A pulsing black hole in the centre of a distant galaxy sheds light on black hole and galaxy formation. How fast are black holes rotating and how does that rotation change over its life-span?

    Huge thanks to Prof. Geraint Lewis and study author Dr. Dheeraj Pasham.

    A loud quasi-periodic oscillation after a star is disrupted
    by a massive black hole

    Special thanks to Patreon supporters:
    Donal Botkin, James M Nicholson, Michael Krugman, Nathan Hansen, Ron Neal, Stan Presolski, Terrance Shepherd

    Music from Colorful animation 4 serene story 2 To the stars 01 Black Vortex

    Animations by Alan Chamberlain and courtesy of NASA

  • Can Humans Sense Magnetic Fields?


    Research has found some human brains can pick up on rotations of geomagnetic-strength fields as evidenced by drops in alpha wave power following stimulus. For more, see

    Huge thanks to:
    Prof. Shinsuke Shimojo, Connie Wang, and Isaac Hilburn, plus Prof. Joe Kirschvink. Their lab:

    Special thanks to Patreon supporters:
    Donal Botkin, James M Nicholson, Michael Krugman, Nathan Hansen, Ron Neal, Stan Presolski, Terrance Shepherd

    Additional filming by Whitney Clavin

  • The 6 SECRETS To Completely HEAL YOUR BODY & MIND | Marisa Peer & Lewis Howes


    Marisa Peer was listed in Tatler’s Guide to Britain’s 250 Best Practitioners and was the only woman on the Men’s Health’s list “Best of British.” She has spent 25+ years working with an extensive client list, including royalty, rock stars, actors, professionals, Olympic athletes, CEOs, and media personalities. She has developed her own style that is frequently referred to as “life changing.”

    Marisa also studied hypnotherapy at the Hypnotism Training Institute of Los Angeles, known as the best hypnotherapy training establishment in the world. She developed her own brand of treatment, Rapid Transformational Therapy, which is a combination of hypnosis, neuro-linguistic programming, and cognitive behavioral therapy. By guiding her patients into a state of relaxation and hypnosis, Marisa Peer is better able to find the root of psychological distress and provide suggestions in order to heal that distress.

    Marisa Peer also started the radical #iamenough movement. By just saying those three words repeatedly – I am enough – you can change your brain’s thought patterns and come to a place of self-love.

    Marisa is the bestselling author of several books, including I Am Enough: Mark Your Mirror and Change Your Life, and makes frequent appearances on TV and radio. She’s helped thousands of people overcome a variety of issues, and is motivated to train others to do the same. I was honored to have Marisa Peer speak on my podcast.

    The way we feel really comes down to the pictures we have in our head and the words that we say. It’s as simple as that.



    I wanted to compare these bench vises my way. I put these 12 vises through 3 different tests to identify their weak points. The first test is a maximum clamping force with just the handle. This is important because this is how well it will hold your work. The next test is a shock load test. You see all the weak points when you hit it with a big hammer. Then finally a maximum clamping force with a 4 foot cheater bar. The only way to find the weak spot is to break it. This was a really fun video to make. Thank you for watching and I can't wait to show you whats next.

    US Store:

    EU Store:

    16 Vise Build:

    Here are the links to some of the vises we tested in this episode provided for your reference. We may receive compensation from Amazon if you purchase using these links. These links are not an endorsement of the products.

    Yost Vises ADI-5, 5 Inch 130,000 PSI Austempered Ductile Iron Bench Vise with 360-Degree
    Swivel Base

    Yost Vises 750-DI 5 Heavy-Duty Multi-Jaw Rotating Combination Pipe and Bench Vise with
    360-Degree Swivel Base and Head

    Wilton Tools 28810 845M Mechanics Pro Vise with 4-1/2 Jaw Width

    JET 10025 ATV All-Terrain Vise, 5

    Wilton 11127 675 5-1/2-Inch Jaw Width by 5-Inch Opening Utility Workshop Vise

    Dewalt DXCMQRV5 Heavy-Duty Quick Release Bench Vise, 5”

    Yost Vises 905-AS 5 Heavy Duty Steel Bench Vise

    Heuer Vise

    Harbor Freight Vise

  • Why Your Brain Thinks These Strawberries Are Red | Science Of Illusions | WIRED


    What is color constancy and how does it trick our brain into seeing colors that aren't really there? WIRED's Robbie Gonzalez and neuroscientist David Eagleman use ambiguous photographs and giant props to explain light, color and the science of illusions.

    Want to try switching the colors you see on the shoe illusion?

    Follow this link if you see the shoes as grey and teal:

    Follow this link if you see the shoes as pink and white:

    Still haven’t subscribed to WIRED on YouTube? ►►
    Get more incredible stories on science and tech with our daily newsletter:

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    WIRED is where tomorrow is realized. Through thought-provoking stories and videos, WIRED explores the future of business, innovation, and culture.

    Why Your Brain Thinks These Strawberries Are Red | Science Of Illusions | WIRED

  • Boarding a US NAVY NUCLEAR SUBMARINE in the Arctic - Smarter Every Day 240


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    Upcoming videos will explore what life on a submarine is like. Click here if you want to sub ????:
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    Note: The US Navy put no restrictions on me about what I should say or how I should present what I learned on this trip. Other than making sure my footage was cleared for Operational Security, I am free to say whatever I want about this experience.

    Another note: The Navy did not ask me to provide a link to their website (or do anything for that matter), but I’m going to provide a link because I want smart people to become submariners. The US Navy continues to provide stability and security in ways no other organization on earth does. If you are interested to find out how you can join the Navy you can visit the website here:

    There are tons of interesting career opportunities out there that I never knew about:

    The US Navy has several options such as engineer, pilot, submariner, logistics, accountant, medical doctor, and even Public Affairs specialist. I continue to be impressed by people that I meed who spent time in the Navy. I worked with various people during the course of filming this video and they were all top notch.

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  • Parallel Worlds Probably Exist. Here’s Why


    The most elegant interpretation of quantum mechanics is the universe is constantly splitting
    A portion of this video was sponsored by Norton. Get up to 60% off the first year (annually billed) here: or use promo code VERITASIUM

    Special thanks to:
    Prof. Sean Carroll
    His book, a major source for this video is 'Something Deeply Hidden: Quantum Worlds and The Emergence of Spacetime'

    Code for solving the Schrödinger equation by Jonny Hyman available here:

    I learned quantum mechanics the traditional 'Copenhagen Interpretation' way. We can use the Schrödinger equation to solve for and evolve wave functions. Then we invoke wave-particle duality, in essence things we detect as particles can behave as waves when they aren't interacting with anything. But when there is a measurement, the wave function collapses leaving us with a definite particle detection. If we repeat the experiment many times, we find the statistics of these results mirror the amplitude of the wave function squared. Hence the Born rule came into being, saying the wave function should be interpreted statistically, that our universe at the most fundamental scale is probabilistic rather than deterministic. This did not sit well with scientists like Einstein and Schrödinger who believed there must be more going on, perhaps 'hidden variables'.

    In the 1950's Hugh Everett proposed the Many Worlds interpretation of quantum mechanics. It is so logical in hindsight but with a bias towards the classical world, experiments and measurements to guide their thinking, it's understandable why the founders of quantum theory didn't come up with it. Rather than proposing different dynamics for measurement, Everett suggests that measurement is something that happens naturally in the course of quantum particles interacting with each other. The conclusion is inescapable. There is nothing special about measurement, it is just the observer becoming entangled with a wave function in a superposition. Since one observer can experience only their own branch, it appears as if the other possibilities have disappeared but in reality there is no reason why they could not still exist and just fail to interact with the other branches. This is caused by environmental decoherence.

    Schrodinger's cat animation by Iván Tello
    Wave functions, double slit and entanglement animation by Jonny Hyman
    Filming of opening sequence by Casey Rentz

    Special thanks to Mithuna Y, Raquel Nuno and Dianna Cowern for feedback on the script

    Music from Experimental 1 Serene Story 2 Seaweed Colorful Animation 4

  • Laws & Causes


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  • The Science Behind the Butterfly Effect


    Chaos theory means deterministic systems can be unpredictable. Thanks to LastPass for sponsoring this video. Click here to start using LastPass:
    Animations by Prof. Robert Ghrist:

    Want to know more about chaos theory and non-linear dynamical systems? Check out:

    Butterfly footage courtesy of Phil Torres and The Jungle Diaries:
    Solar system, 3-body and printout animations by Jonny Hyman
    Some animations made with Universe Sandbox:
    Special thanks to Prof. Mason Porter at UCLA who I interviewed for this video.

    I have long wanted to make a video about chaos, ever since reading James Gleick's fantastic book, Chaos. I hope this video gives an idea of phase space - a picture of dynamical systems in which each point completely represents the state of the system. For a pendulum, phase space is only 2-dimensional and you can get orbits (in the case of an undamped pendulum) or an inward spiral (in the case of a pendulum with friction). For the Lorenz equations we need three dimensions to show the phase space. The attractor you find for these equations is said to be strange and chaotic because there is no loop, only infinite curves that never intersect. This explains why the motion is so unpredictable - two different initial conditions that are very close together can end up arbitrarily far apart.

    Music from The Longest Rest A Sound Foundation Seaweed

  • The Launch of Perseverance to Mars


    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

  • Which Way Will the Water Go? - Smarter Every Day 226


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    Steve Mould's Channel:

    Click here if you're interested in subscribing:
    ⇊ Click below for more links! ⇊

    Someone made an interactive model of this!


    (If I did this right these should be working Amazon affiliate links to purchase the stuff I like to use. When people purchase from these links it will support Smarter Every Day.)

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    Travel Tripod:
    My Backpack:
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    Favorite Bidet:
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    Favorite Shoes:
    Everyone needs a snatchblock:
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    Tweet Ideas to me at:

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    Ambiance, audio and musicy things by: Gordon McGladdery

    If you feel like this video was worth your time and added value to your life, please SHARE THE VIDEO!

    If you REALLY liked it, feel free to pitch a few dollars Smarter Every Day by becoming a Patron.

    Warm Regards,


  • Do we need a Theory of Everything?


    I get constantly asked if I could please comment on other people’s theories of everything. That could be Garrett Lisi’s E8 theory or Eric Weinstein’s geometric unity or Stephen Wolfram’s idea that the universe is but a big graph, and so on. First I explain what physicists mean by a theory of everything and by grand unification (or a grand unified theory, respectively). Then I explain why the current approaches are no very promising but why, forgive me, I nevertheless think it's good to have them.

    You can help finance my videos by donating here:

  • The Story Of Energy With Professor Jim Al-Khalili | Order and Disorder | Spark


    The great 19th-century Austrian physicist, Ludwig Boltzmann was one of the most important proponents of the idea that all matter is made of atoms.

    Today no one doubts this is true but in Boltzmann's day it was a controversial idea and many of his contemporaries disagreed with him. But Boltzmann used brilliant mathematical arguments to show that many aspects of the world we observe, like the behaviour of heat, can be explained if one accepts that atoms are real.

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    Any queries, please contact us at:

    #JimAlKhalili #Energy #Thermodynamics #spark #sparkdocumentary #sciencedocumentary

  • The Four Fundamental Forces of nature - Origin & Function


    • Signup for your FREE trial to The Great Courses Plus here:
    if you took a notebook, a plastic bottle, a toaster, and a glass container and burned them in a fire hot enough, around 10^31 degrees Celsius, all the particles and forces, would become one entity. This is what is believed to have existed at the moment of the big bang.

    All matter is composed of 6 quarks and 6 leptons and their 12 antiparticle pairs. But matter is subject to 4 fundamental forces that result in every action in the universe. These 4 forces are the strong force which binds the nuclei of atoms together, the weak force which is responsible for some kinds of radioactivity, electromagnetism responsible for the root cause of chemistry, and gravity which binds us to the earth.

    The best way to understand this and how these forces emerged is to visualize what happened at the big bang, when everything was one. Time began at the smallest time, Planck time, 10^-43 seconds. We are ignorant of anything that might have occurred prior to this 1st epoch of existence, called the Planck Epoch.

    All the forces and particles were in a point smaller than the size of a proton. Gravity separated from everything else, as it was the first force to separate out from the other 3 forces. The temperatures at this stage were 10^31 degrees Celsius, and the energies were in the range of 10^19 giga electron volts. The strings of string theory and the loops of loop quantum gravity, if those theories are correct, come into existence here.

    The next era, called the Grand Unified epoch lasts from the first Planck second up to about 10^-35 seconds. The Strong and weak force and electromagnetism were all unified. But shortly after this period, the strong force separated from the other two - electromagnetism and the weak force, which were united as one force called the electroweak force. Temperatures were now around 10^26 degrees Celsius. Cosmic inflation occurred. The universe which went from tinier than the size of a proton to the size of a grapefruit.

    At 10^-12 seconds, called the quark epoch, the electroweak force split into the weak force and electromagnetism. So at this point, all the 4 forces became distinct. The temperature of the universe cooled to 10^15 degrees Celcius, and energies are about 100 GeV. We know a lot about the universe up to this era because such energy levels can be modeled in particle accelerators. The Higgs field exists at this stage.

    That brings us to today, 13.8 billion years later, where the average temperature of the universe is -270 degrees C, and energy is 0.25 eV

    Gravity and electromagnetism are similar in that their mathematical formulas look nearly identical. Newtons law of universal gravitation is F= G Mm/r^2 . were G is Newton’s gravitational constant. Coulomb’s law of electric force between charged bodies is F = k Qq/r^2 where k is Coulomb’s constant.

    This means that the earth has a gravitational effect not just on the moon, but also some effect on every other massive object in the universe. This is a very small effect, but it is non zero. And since gravity effects all masses, this effect is the most influential force on a cosmic scale.

    But the electrostatic force between charges also extends infinitely far away. And this force is much greater than the force of gravity - 10^36 times greater. So why isn’t electromagnetism the most dominant force in the universe? ...because on large scales electric charges of most objects tend to cancel each other out. Large objects tend to be neutral. If large things were not electrically neutral, this force would completely dominate the universe. But Electromagnetism still has a big influence. It is the basis of all chemistry.

    So if electromagnetism is so strong, then what keeps multiple protons bound in the nucleus of atoms? They are kept glued together with a force one hundred times stronger, the strong nuclear force. However, it extends only as far as the width of a proton. This force is not simply the opposite of electromagnetism because it also holds electrically neutral atoms in the center of atoms.

    The release of this force is the energy behind nuclear bombs. The fission and fusion of atoms releases huge amounts of binding energy from the nucleus, which results from the strong force. It is also responsible for most of the mass of any object, not the Higgs Field.
    The weak force is responsible for beta radiation, which is the emission of electrons or positrons. One of the most important processes in nature is the beta decay of a neutron. If this decay did not occur, then the universe would have been full of neutrons, and no atoms would have ever formed. And we would not have life. But it’s effective length is only about one thousandth the diameter of a proton.

  • Why People are Always Fighting Over the Thermostat


    Negotiating thermostat settings can be really frustrating, but your officemate isn't trying to freeze you out on purpose. Stefan explains the science behind why people experience temperatures differently.
    Fun fact: Stefan wears a jacket inside year round.

    Hosted by: Stefan Chin

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  • Simulating the Evolution of Aggression


    Try Brilliant's Computational Biology course:
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    Books that inspired this video and have more information:
    - The Selfish Gene, Richard Dawkins,
    - An Introduction to Behavioral Ecology,
    (If you decide to buy one of these books, doing so through one of these links helps support the channel)

    Thanks to supporters on Patreon, especially:
    Vladimir Duchenchuk, Victor Anne, Noah Healy, Zachariah Richard Fournier, Patrick Gorrell, Jordan Scales, Jacob Maes, Kairui Wang, Josh Levent,, Marcial Abrahantes, Feimeng Zheng, Eric Helps, Sean Barker, Leonardo Kluppel, Tamas Gombkoto, Ben Kamens, Ben Komalo, Victor Moisescu, Alexander Mahone, Bjarke, Aurélien Géron, Daniel Giavedoni, Jeff, Jason Prado, Ryan Mahuron, Laura Picard, Anselm Eickhoff, Christy Serbus, 3blue1brown, Paul Straw, Roy Steves, Max Kaye, Elliot Press, ThePotatoGuy, Kevin Holesh, Talon Howitt, Mitchell Douglass, Sam Van Cise, Rikard Eide, Garrett F, Brian, Daniel Schramm, Wyatt Nelson, Mr_Chimick

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    Made with Blender and python.
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    Several other inputs into the graphics are from public domain contributions to

  • World’s Largest Camera Lens


    The world's largest digital camera is currently being assembled at a warehouse in California.
    PBS Survey: 

    We caught the short window of time to see the camera's massive lens. 

    If you liked this video check out these:
    Giant Truck Camera Obscura 
    Could you replace your eye with a camera? 

    Thanks to the LSST team and everyone at SLAC!

    Creator/Host: Dianna Cowern
    Editor: Levi Butner
    Research: Tamia Williams
    Research & Writing: Dianna & Imogen Ashford


  • Ellipsoids and The Bizarre Behaviour of Rotating Bodies


    Derek's video: The Bizarre Behavior of Rotating Bodies, Explained

    Based on this amazing footage: Dancing T-handle in zero-g

    Terence Tao's original answer, with update.

    Support me on Patreon and I can make more video like this!

    We are sat so close because we filmed this in the “before times” of late 2019.

    Huge thanks to Helen Czerski for spinning a book in zero-G for us.

    Cosmic Shambles (who convinced ESA to launch Helen) also have a Patreon:

    Ben Sparks made the ellipsoid animations for me. Check out their GeoGebra files here:

    Rotating 3D book was thanks to Tim Waskett of Stone Baked Games.

    There are plenty more Matt and Hugh videos to learn about moments of inertia and suchlike.

    Hugh Hunt is the Cambridge University Reader in Engineering Dynamics and Vibration. I know!

    Zero G footage courtesy The Cosmic Shambles Network working in association with the European Space Agency. In flight footage shot by Melanie Cowan. External plane footage courtesy Novespace.

    - At 11:00 and 14:23 I say the axes correspond to the axes of rotation but technically they represent the three different directions of spin. Which is why they are labelled with omegas representing the angular velocities in those directions.
    - At 05:52 the ellipsoid equation should be “volume” not “area”. First pointed out by Ihsan Khairir. My fault for not paying attention editing the text after copying the previous equations.
    - Oh my goodness. At 11:50 we missed an “L” in ellipsoid. First pointed out by Daniel Burger. I’m so embarrassed.
    - Let me know if you spot any other mistakes. Or, you know, make a whole video about it.

    As always: thanks to Jane Street who support my channel. They're amazing.

    Filming and editing by Trunkman Productions
    Additional filming by Melanie Cowan
    Audio by Peter Doggart
    Music by Howard Carter
    Design by Simon Wright and Adam Robinson

    MATT PARKER: Stand-up Mathematician
    US book:
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  • Intermediate Axis Theorem - Explained


    A demonstration of the Intermediate Axis Theorem (also known as the Tennis Racket Theorem or the Dzhanibekov effect). Visuals provided by Kerbal Space Program.

    Physics vs KSP:

    Stopping Spinning Rockets:

    Orbital Mechanics:

    Drafting Rockets:

    Dance, Don't Delay by Twin Musicom is licensed under a Creative Commons Attribution license (

  • BIZARRE spinning toys


    Spinning toys and tops have unusual behaviors. The famous tippe top flips itself over and spins on its stem. The PhiTOP stands up on its end, which you can also do with a hard-boiled egg. These behaviors all have to do with torque and angular momentum, like a bicycle wheel precessing around a rope due to gyroscopic behavior.

    Defining Gravity with Tim Blais:

    A Cappella Science:

    Crash Course Physics:

    Help us translate our videos!

    Creator: Dianna Cowern
    Writer: Sophia Chen
    Editor: Jabril Ashe
    Animator: Kyle Norby


    More resources:

    Music: APM

  • Rotating Solid Bodies in Microgravity


    Saturday Morning Science

  • Dancing T-handle in zero-g, HD


    HD video of the installation handle on Space-DRUMS in free floating rotation showing a bi-stable state due to intermediate moments of inertia.

  • Spinning Disk Trick Solution


    ZoggFromBetelgeuse's solution:
    This is a preliminary solution to the spinning disk trick based on the commonly cited tippe top explanation. I have my doubts that it tells the whole story because the disk seems to tilt, so the argument about constant angular velocity is in doubt. I wonder if the weight of the disk plays a more important role in making it flip. Plus, I think the disk appears to roll without slipping while the lighter side is moving down. This violates one of the assumptions of the tippe top explanation. So why am I publishing this now? I feel bad it has been two weeks and I haven't posted the answer yet so let's consider this a starting point for a work in progress...

  • Rotation in Space


  • Rotating bodies in microgravity and cat flip!!!


    Spinning objects have strange instabilities known as the Dzhanibekov effect or tennis racket Theorem. Also i show video rotating rigid and solid bodies in space. At last you can see how cat flip on earth!

  • El Extraño Comportamiento de los Objetos en Rotación | EXPLICADO


    Los objetos giratorios tienen inestabilidades extrañas conocidas como el efecto Dzhanibekov o el teorema de la raqueta de tenis: este video ofrece una explicación intuitiva.????SUSCRÍBETE para ver todos nuestros videos:

    Video en Inglés del canal @Veritasium : The Bizarre Behavior of Rotating Bodies, Explained

    Explicación profesor Terry Tao:

    La raqueta de tenis en rotación
    Ashbaugh, M.S., Chicone, C.C. & Cushman, R.H. J Dyn Diff Equat (1991) 3: 67.

    El efecto de Janibekov y las leyes de la mecánica.
    Petrov, A.G. y Volodin, S.E. Dokl Phys. (2013) 58: 349.

    Asteroides que caen
    Prave y col.

    El cálculo exacto del movimiento del cuerpo rígido libre y su uso en métodos de división
    SIAM J. Sci. Comput., 30 (4), 2084–2112
    E. Celledoni, F. Fassò, N. Säfström y A. Zanna

    Animaciones de Iván Tello e Isaac Frame

    Un agradecimiento especial a las personas que discutieron este video conmigo:
    Astronauta Don Pettit
    Henry Reich de MinutePhysics
    Grant Sanderson de 3blue1brown
    Vert Dider (canal ruso de YouTube)

    Servicios de doblaje:
    Twitter: @Unilingo_HQ
    Traductora: Paula Salomone
    Voz de doblaje: Pato Lago, Diego Rivas,
    Ingeniero de sonido: Gastón Adriel Álvarez
    Edición y post-producción de video: Juan Caille Tornquist

  • Simulation of the Dzhanibekov Effect


    This is an AstroGrav video that shows a simulation of the Dzhanibekov Effect, in which a rotating body (such a wingnut on a space station) periodically 'flips' through 180 degrees, counter to intuition.

    The rigid body is simulated with seven spheres that are held together by their mutual gravitational attraction. At the center is a small white sphere whose purpose is just to prevent the other spheres from collapsing towards each other. The remaining six spheres are arranged in opposing pairs with masses in the ratio 4 : 2 : 1, with the pair of intermediate masses colored blue. They are in different shades so as to make the 'flipping' clearer.

    If the simulation is run within AstroGrav, the masses and velocities of the balls can easily be changed to see what effect it has. Since different computers run at different speeds, you may need to edit the evolution time step to get the simulation to evolve at an acceptable rate.

  • International Toys in Space: Spinning Top


    Astronaut Peggy Whitson investigates how a traditional spinning top performs in a microgravity environment. Whitson narrates the video.

  • Tennis racket theorem


    FreeCAD + MBDyn tennis racket theorem simulation

    Explanation here:

  • Dzhanibekov effect demonstration in microgravity, NASA.


    Principal axes of a tennis racket.
    The tennis racket theorem or intermediate axis theorem is a result in classical mechanics describing the movement of a rigid body with three distinct principal moments of inertia. It is also dubbed the Dzhanibekov effect, after Russian cosmonaut Vladimir Dzhanibekov who rediscovered one of the theorem's consequences while in space in 1985

  • Axes of Rotation Demo: Wood Block


    This is a demonstration of the principal axes of rotation, and the instability of the axis with the intermediate value of the moment of inertia, using a wood block.

    This demonstration was created at Utah State University by Professor Boyd F. Edwards, assisted by James Coburn (demonstration specialist), David Evans (videography), and Rebecca Whitney (closed captions), with support from Jan Sojka, Physics Department Head, and Robert Wagner, Executive Vice Provost and Dean of Academic and Instructional Services.

  • The Dzhanibekov Effect : É bom saber disso em 4:60 com Zmaro


    Para colaborar acesse:
    Conheça o conceito: The Dzhanibekov Effect ou Tennis Racket Theorem, ou seja: Teoria da raquete de tenis, também chamado de comportamento bizarro dos corpos em rotação (the Bizarre Behavior of Rotating Bodies, Explained).
    Parece algo para físicos, mas não é aula de física não e sim um conceito interessando que é bom sabermos e que serve para nos alertar das leis da natureza que podemos desconhecer quando voamos com nossos drones.

    vídeo que citei:

    Esta em inglês, mas assista o vídeo que ensino como traduzir para português legendado

    Confira os Cupons de Desconto, produtos em promoção, Promoções da china, coisas baratas, coisas legais, e afins na banggood e ainda ajude o Zmaro a ganhar moral com eles. Veja o link

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    Grupos do Zmaro no Whatsapp e amigos:
    Fico a disposição: fone/whatsapp: 16 99116 6498

    Aprenda a comprar da china, veja o vídeo

    se for comprar algo use o link acima para ajudar o Zmaro

    humor inteligente de forma descontraída
    assista os vídeos do Programa Zmaro de tv/webtv em

    Escute o Zmaro em formato podcast no seu player, veja o link
    ou adicione o link:


  • The Intermediate Moment of Inertia - A Short Story


    From the director of Cyberkiller comes a new but informative tale of one man who travels on a thrilling journey across multiple dimensions. Join Seth Chin, Garrett Miller and Davis Lenover in The Intermediate Moment of Inertia!

    Just kidding! This video is a take on a physics magic trick involving, the intermediate moment of inertia (Tennis Racket Theorem)!

    --------------------Reference Links--------------------
    Intermediate Axis Theorem - Explained, YouTube,

    The Bizarre Behavior of Rotating Bodies, Explained, YouTube,

    Tennis Racket Theorem, YouTube,

    Dancing T-handle in zero-g, HD, YouTube,

    Chapter 1, Centres of Mass, University of Victoria,

    Chapter 2, Moment of Inertia, University of Victoria,

    Chapter 3, Systems of Particles, University of Victoria,

    Chapter 4, Rigid Body Rotation, University of Victoria,

    Special thanks to Ewan, Pablo, Alisher and Cameron for being our interviewees during this presentation!
    Also a huge thanks to Devon Miller-Junk and Cameron Orr for helping us bring the explanation of this content down to earth!

    All audio played in this video is subject to fair use terms and credit goes to their respective owners.

  • The Unstable Spin Mystery, Part 1


    This is the part 1 of my series explaining my theory of the Intermediate Axis Theorem in a non-mathematical way. In this video, I go over the reason why the rotational axis of maximum moment of inertia is stable. Subscribe for part 2, where I explain the other two axes of rotation.
    Computer website sources:

  • Partida N°37 ????????!!


  • AppDynSys : Intermediate Axis Theorem : Perturbations


    The Euler equations for the rotation of a solid asymmetric body about its three principal axes have some interesting features. The Medial Axis Theorem says that rotation about the middle axis is unstable, in constrast to rotatin about the shortest and longest axes. Illustrated here is a solid body rotated about the three axes. From left-to-right, a small angular perturbation in initial conditions is introduced. Rotation about the longest and shortest axes is roughly the same, even with the small perturbation; however, the middle-axis rotation experiences wild swings where it completely flips over. That is the instability.

  • Spinning



    Jake unboxing the latest Curiosity Box (SPOILERS):

    Other great videos on this topic:

    The gyro effect explained, without math from Matthias Wandel

    also see

    Gyroscopic precession -- An intuitive explanation from TheHue's SciTech

    Gyroscopic Precession from Veritasium

    Anti-Gravity Wheel? from Veritasium

    Bizarre spinning toys from Physics Girl

    Can a satellite do a yo-yo trick? from Practical Engineering

    wiki pages about gyroscopes and circular motion:

    centripetal force:

    xkcd on Centrifugal Force:

    Eötvös effect:

    Music by and

    Good-lookin' 3D graphics by Eric Langlay:

    mid-tier 2D animations by me.


  • The Intermediate Axis Theorem /// Breakthrough Junior Challenge Finalist 2017


    A nice little tid bit on a phenomenon explained by the Intermediate Axis Theorem.


    Marty Gots a Plan Kevin MacLeod (
    Licensed under Creative Commons: By Attribution 3.0 License

  • The Unstable Spin Mystery, Part 2


    This video explains my theory of the intermediate axis theorem, which is a non-mathematical logical explanation of why two of the axes of rotation are stable, but the third one is unstable. This video explains why the axis of rotation that goes through the longest dimension of an object is unstable. Subscribe for part 3! Dictionary web page source:

  • Spinning Tube Trick Explained


    When a tube spins with an X and an O labelled at either end, why do we see only one letter during the rotation?

  • Bizarre behavior - Intro to Psychology


    This video is part of an online course, Intro to Psychology. Check out the course here:

  • Dzhanibekov Effect


    A simulation in Simbody showing the non-intuitive rigid body behavior known as the Dzhanibekov Effect. It is best seen in zero gravity; see space station video: This was integrated with accuracy 1e-5. Total energy is displayed in the video and is conserved to about 5 decimal places as it should be. The integrator was Runge Kutta Merson (4th order).

  • AppDynSys : Intermediate Axis Theorem : Flow


    Why is rotation about the middle axis unstable? If you examine a surface of fixed energy and look at the dynamics, you get six equilibria in three pairs -- rotation about each axis CW and CCW. These equilibria are centers for the longest and shortest axes. But for the middle axis -- the equilibria are saddles! The flipping seen in the previous video corresponds to travelling close to a heteroclinic cycle between saddle points.

  • Tennis Racket Theorem


    (sorry about the misspelling of principal as principle - oops!) This demonstration shows a fascinating observation about the rotation of a tennis racket (or ping-pong paddle) is that the racket flips over if rotated freely about one of its primary axes. This is a result of Euler's Equations of Motion and the moments of inertia about the various axes being time-independent. The so-called Tennis Racket Theorem applies to the case where the moments of inertia about the principal axes are spaced: I1 ≪ I2 ≪ I3. The theorem states that rotations about axes #l and #3 are much more stable than about axis #2, even though I2 may be very close to I3 in value.

  • The CED: No really, it coulda made sense!


    You can support this channel on Patreon! Link below
    It’s seriously not that crazy of an idea. RCA might have pulled this off in a couple of ways, and in this video we explore those new angles.

    First of all, here’s part one;

    Here are a few videos that show what goes on inside the later players:

    The first link is a quick view, the second link includes more explanation of the player itself.

    And where there are some links, you’ll find more links!

    Technology Connections on Twitter:

    The TC Subreddit

    Technology Connections 2 (the channel where I sometimes talk about stuff and generally don’t prepare for anything):

    You can support this channel on Patreon! It has been amazing what Patreon has done for this channel, but also for me (your dorky host) personally. Through the support of people just like you, Technology Connections has become my job and I am so excited and thankful for it! If you’d like to join the fine folks in a pledge to help the channel stay as weird as it is (and maybe, just maybe, get even weirder!), please check out my Patreon page. Thank you for your consideration!

    And thank you to the following patrons!
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  • Bullet Block Explained!


    Watch the bullet block experiment first:
    Click for a free audiobook from Audible:
    An interactive vignette of the bullet block

    Can you figure out the spinning disk?

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

    Web comic:
    Wired Blog:
    Science Blogs:
    Scientific American:
    Le's Blog:

    Video responses from which I borrowed:

    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






    Arguably the best mathematician alive Soviet era secrets and the end of the world so in cosmonaut Vladimir Jana Bekoff was tasked with saving the Soviet space station Salyut 7 which had completely shut down the mission was so dramatic that the Russians made a movie out of it in 2017 and after rescuing the space station Jana back off unpacked supplies sent up from Earth which were locked down with a wing nut and as the wing nut spun off the bolt he noticed something strange the wing nut maintained its orientation for a short time and then it flipped 180 degrees and as he kept watching it flipped back a few seconds later and it continued flipping back and forth at regular intervals.

    This motion wasn't caused by forces or torque supplied to the wing nut there were none and yet it kept flipping it was a strange and counter intuitive phenomenon one that the Russians kept secret for 10 years.




    Navodno najboljI živi matematičar iz sovjetske tajne ere je objavio tajnu, pa je kosmonaut Vladimira Jana Bekoff dobio zadatak da spasi sovjetsku svemirsku stanicu Saljut 7, koja se je u potpunosti isključilai i ugrozila misiju. Bilo toliko dramatična da su Rusi od nje snimili film. 2017. i nakon spašavanja svemirske stanice Jana vratila je neraspakovane potrepštine poslane sa Zemlje, koje su bile zaključane sa krilatom maticom.

    I kad je krilata matica odletila sa vijka, primijetio je nešto neobično da je krilata matica kratko zadržala orijentaciju, a zatim se okrenula za 180 stepeni i dok je neprestano gledao krilata matica se je okrenula nazad a nekoliko sekundi kasnije i nastavila je da se kreće unazad i nazad, u pravilnim intervalima.

    To kretanje nije bilo uzrokovano silama ili obrtnim momentom koji je dolazio do krilate matice, ali nije ih bilo, a ipak je neprestano se okretala, to je bila čudna i kontra aktivna pojava koju su Rusi držali u tajnosti 10 godina.