How far would a basketball with backspin go? Rotor wing experimental aircraft: E-ship 1: Corner kick by Kyle: How Ridiculous World Record Basket:
For more on spin, check out: This video was supported by TechNYou: A quantum computer works in a totally different way from a classical computer. Quantum bits or 'qubits' can exist in a superposition state of both zero and one simultaneously. This means that a set of two qubits can be in a superposition of four states, which therefore require four numbers to uniquely identify the state. So the amount of information stored in N qubits is two to the power of N classical bits. Thank you to Andrea Morello and UNSW. For more info, check out:
MinutePhysics on permanent magnets: Subscribe to Veritasium: Support Veritasium- get a t-shirt: Subscribe to MinutePhysics: Magnetism seems like a pretty magical phenomenon. Rocks that attract or repel each other at a distance - that's really cool - and electric current in a wire interacts in the same way. What's even more amazing is how it works. We normally think of special relativity as having little bearing on our lives because everything happens at such low speeds that relativistic effects are negligible. But when you consider the large number of charges in a wire and the strength of the electric interaction, you can see that electromagnets function thanks to the special relativistic effect of length contraction. In a frame of reference moving with the charges, there is an electric field that creates a force on the charges. But in the lab frame, there is no electric field so it must be a magnetic field creating the force. Hence we see that a magnetic field is what an electric field becomes when an electrically charged object starts moving. I was inspired to make this video by Prof. Eric Mazur Huge thank you to Ralph at the School of Physics, University of Sydney for helping us out with all this magnetic gear. Thanks also to geology for loaning the rocks. This video was filmed in the studio at the University of New South Wales - thanks to all the staff there for their time and support. Music: Firefly in a Fairytale, Nathaniel Schroeder, and Love Lost (Instrumental) by Temper Trap licensed from CueSongs.com
Increasing entropy is NOT the only process that's asymmetric in time. Check out the book: This video was co-written by Daniel Whiteson and Jorge Cham You can also check out PhD Comics: Special thanks to Patreon supporters: Tony Fadell, Donal Botkin, Michael Krugman, Jeff Straathof, Zach Mueller, Ron Neal, Nathan Hansen, Joshua Abenir Support Veritasium on Patreon: Original paper on parity violation by the weak force by Lee and Yang: More on B-meson oscillations and time reversal violation: Physics World Article: Original paper: Physics consultant: Prof. Stephen Bartlett Studio filming by Raquel Nuno
How does a transistor work? Our lives depend on this device. Support Veritasium on Patreon: Subscribe to Veritasium - it's FREE! When I mentioned to people that I was doing a video on transistors, they would say as in a transistor radio? Yes! That's exactly what I mean, but it goes so much deeper than that. After the transistor was invented in 1947 one of the first available consumer technologies it was applied to was radios, so they could be made portable and higher quality. Hence the line in 'Brown-eyed Girl' - going down to the old mine with a transistor radio. But more important to our lives today, the transistor made possible the microcomputer revolution, and hence the Internet, and also TVs, mobile phones, fancy washing machines, dishwashers, calculators, satellites, projectors etc. etc. A transistor is based on semiconductor material, usually silicon, which is 'doped' with impurities to carefully change its electrical properties. These n and p-type semiconductors are then put together in different configurations to achieve a desired electrical result. And in the case of the transistor, this is to make a tiny electrical switch. These switches are then connected together to perform computations, store information, and basically make everything electrical work intelligently. Special thanks to PhD Comics for awesome animations: And thanks to Henry Reich and Vanessa Hill for reviews of earlier drafts of this video. Music: Kevin MacLeod (incompetech.com) Decisions
A head-vaporizing laser with a perfect wavelength detecting sub-proton space-time ripples. Huge thanks to Prof Rana Adhikari and LIGO: Here's how he felt when he learned about the first ever detection: Thanks to Patreon supporters: Nathan Hansen, Donal Botkin, Tony Fadell, Saeed Alghamdi, Zach Mueller, Ron Neal Support Veritasium on Patreon: A lot of videos have covered the general overview of the discovery of gravitational waves, what they are, the history of the search, when they were found but I wanted to delve into the absurd science that made the detection possible. When scientists want one megawatt of laser power, it's not just for fun (though I'm sure it's that too), it's because the fluctuations in the number of photons is proportional to their square root, making more powerful beams less noisy (as a fraction of their total). The smoothest mirrors were created not for aesthetic joy but because when you're trying to measure wiggles that are a fraction the width of a proton, a rough mirror surface simply won't do. Filmed by Daniel Joseph Files Music by Kevin MacLeod, Black Vortex (appropriately named) Music licensed from Epidemic Sound Observations 2 (also appropriately named)
Einstein's classic thought experiment involves sitting on a train travelling at the speed of light. If you hold a mirror in front of your face, will you see your reflection in a mirror? How could light from your face reach the mirror if the mirror is travelling away from you? But it would be a pretty spooky train if you couldn't see your reflection so Einstein felt this solution wasn't realistic. On the other hand if you could see your reflection, it would mean light was travelling at the speed of light inside the train. But that meant the same light observed from outside the train would be going twice the speed of light. This again seems inconsistent. So Einstein resolved that you must see your reflection but that light must travel at the same speed inside and outside the train. The only way this is possible is if space and time are perceived differently by observers inside and outside the train.
Does quantum entanglement make faster-than-light communication possible? What is NOT random? First, I know this video is not easy to understand. Thank you for taking the time to attempt to understand it. I've been working on this for over six months over which time my understanding has improved. Quantum entanglement and spooky action at a distance are still debated by professors of quantum physics (I know because I discussed this topic with two of them). Does hidden information (called hidden variables by physicists) exist? If it does, the experiment violating Bell inequalities indicates that hidden variables must update faster than light - they would be considered 'non-local'. On the other hand if you don't consider the spins before you make the measurement then you could simply say hidden variables don't exist and whenever you measure spins in the same direction you always get opposite results, which makes sense since angular momentum must be conserved in the universe. Everyone agrees that quantum entanglement does not allow information to be transmitted faster that light. There is no action either detector operator could take to signal the other one - regardless of the choice of measurement direction, the measured spins are random with 50/50 probability of up/down. Special thanks to: Prof. Stephen Bartlett, University of Sydney: Prof. John Preskill, Caltech: Looking Glass Universe: Physics Girl: MinutePhysics: Community Channel: Nigel, Helen, Luke, and Simon for comments on earlier drafts of this video. Filmed in part by Scott Lewis: Music by Amarante One Last Time :
Смотреть: "The First Meeting of EDUtubers! ft. CGPGrey, Vsauce, Smarter Every Day, Numberphile +more" онлайн.
Back in 2012, we all met for the first time at BrainSTEM - a conference of science YouTubers, instigated by Henry of MinutePhysics (Thank You Henry!!!) bringing together the most awesome STEM personalities from around the world. People like Vsauce, John Green, Vihart, Destin from Smarter Every Day, CGP Grey, Brady Haran of Numberphile et al. I had an awesome three days hanging out with all the cool people in this video and hopefully this is only the start of many fruitful collaborations to come. Thanks everyone!!! Now this happens to be video 100 for me. It's not really about science, but I think it's pretty awesome because it features all of my YouTube heroes.
My entry to the techNyou Science Ambassadors competition, visit and to find out more about these guys.
It's a little shaky but if you average out the oscillations I think the result is clear. Again, huge thank you's to A/Prof Emeritus Rod Cross, Helen Georgiou, Alex Yeung, and Chris Stewart, Tom Gordon, the University of Sydney Mechanical Engineering shop, Duncan and co. Ralph and the School of Physics.
NOTE: This video will appear in a playlist on Smarter Every Day hence the references to Veritasium. Destin does lots of cool science stuff - check out his channel if you haven't already We have been collaborating on rotational motion, which is timely for some of the videos I've been doing lately. In this video I talk about gyroscopic precession - the wobbling of a spinning top around its axis. This is caused by the torque due to the object's weight. The big idea is that the torque vector increases angular momentum in the direction of torque. So if there is no angular momentum initially, it will cause the system to swing in such a direction that it is rotating with new angular momentum in the direction of the torque. However, if there was angular momentum to begin with, the torque will change the direction of that angular momentum by causing precession.
The Higgs Boson is awesome but it's NOT responsible for most of your mass! Thanks to audible.com for supporting this episode: The Higgs mechanism is meant to account for the mass of everything, right? Well no, only the fundamental particles, which means that electrons derive their mass entirely from the Higgs interaction but protons and neutrons, made of quarks, do not. In fact the quark masses are so small that they only make up about 1% of the mass of the proton (and a similar fraction of the neutron). The rest of the mass comes from the energy in the gluon field. Gluons are massless, but there is so much energy in the field that by E=mc^2 there is a significant amount of mass there. This is where most of your mass comes from and the mass of virtually everything around you. Thanks to Professor Derek Leinweber for his great images, animations and explanations. Check out his site to find out more:
We have just seen the first image of a black hole, the supermassive black hole in the galaxy M87 with a mass 6.5 billion times that of our sun. But what is that image really showing us? This is an awesome paper on the topic by J.P. Luminet: Image of a spherical black hole with thin accretion disk Astronomy and Astrophysics, vol. 75, no. 1-2, May 1979, p. 228-235 Using my every day intuition I wondered: will we see the shadow of the black hole even if we're looking edge on at the accretion disk? The answer is yes because the black hole warps space-time, so even if we wouldn't normally be able to see the back of the accretion disk, we can in this case because its light is bent up and over the black hole. Similarly we can see light from the bottom of the back of the accretion disk because it's bent under the bottom of the black hole. Plus there are additional images from light that does a half turn around the black hole leading to the inner rings. What about the black hole shadow itself? Well initially I thought it can't be an image of the event horizon because it's so much bigger (2.6 times bigger). But if you trace back the rays, you find that for every point in the shadow, there is a corresponding ray that traces back to the event horizon. So in fact from our one observing location, we see all sides of the event horizon simultaneously! In fact infinitely many of these images, accounting for the virtually infinite number of times a photon can orbit the black hole before falling in. The edge of the shadow is due to the photon sphere - the radius at which light goes around in closed orbits. If a light ray coming in at an oblique angle just skims the photon sphere and then travels on to our telescopes, that is the closest 'impact parameter' possible, and it occurs at sqrt(27)/2*r_s Huge thanks to: Prof. Geraint Lewis University of Sydney Like him, I'm hoping (predicting?) we'll see some moving images of black holes tomorrow Prof. Rana Adhikari Caltech Riccardo Antonelli - for excellent images of black holes, simulations and ray-tracing code, check out: The Event Horizon Telescope Collaboration Check out their resources and get your local link for the livestream here: Special thanks to Patreon supporters: Donal Botkin, Michael Krugman, Ron Neal, Stan Presolski, Terrance Shepherd, Penward Rhyme Filming by Raquel Nuno Animation by Maria Raykova
Heisenberg's uncertainty principle tells us that it is impossible to simultaneously measure the position and momentum of a particle with infinite precision. In our everyday lives we virtually never come up against this limit, hence why it seems peculiar. In this experiment a laser is shone through a narrow slit onto a screen. As the slit is made narrower, the spot on the screen also becomes narrower. But at a certain point, the spot starts becoming wider. This is because the photons of light have been so localised at the slit that their horizontal momentum must become less well defined in order to satisfy Heisenberg's uncertainty principle. I based this video on one by Prof. Walter Lewin of MIT: Henry (MinutePhysics) has previously made a video about Heisenberg's Uncertainty Principle where he treats it as less spooky and more a consequence of waves: Sixty Symbols has a great video on Planck's constant: Thanks to the University of Sydney for hosting this experiment, especially to Tom and Ralph for their assistance getting it working. Music: Kevin McLeod (Incompetech.com) Mirage and Danse Macabre
How does a transistor work? Silicon-28 sphere: This episode supported by audible.com: We have looked at how a transistor works, the fundamental unit of classical computers, and how a quantum computer works in theory, taking advantage of quantum superposition to hold exponentially more information than classical computers. Now we look at the practical side of making a quantum bit, or qubit. How do you put it in a state where it is stable? How do you read and write information on it? These processes are described for a solid state qubit - a phosphorous atom in a silicon crystal substrate. Both the electron and the nucleus of the phosphorous atom can be used as qubits. Thanks to A/Prof. Andrea Morello: Thanks to Henry Reich (MinutePhysics) for pushing me to make the explanations and visualizations clearer.
At the Palais de la Decouverte in Paris, they showed me this experiment where a 1kg aluminium plate is levitated above a large coil of wire that is being supplied with 800A of alternating current at 900Hz. This is by far the best demonstration of electromagnetic induction I have ever seen. Back in London, I visited the magnetic lab of Michael Faraday in the basement of the Royal Institution. It was here that he did his groundbreaking work on induction. People had previously observed that current in a wire causes a compass needle to deflect, but more exciting was the prospect of using a magnetic field to generate current. Faraday created his famous induction ring by winding two coils of insulated wire onto an iron ring. When he connected a battery to one coil, a small pulse of current was induced in the other. When the battery was disconnected, current was induced in the other direction. This led Faraday to the conclusion that current was induced in the second coil only when the magnetic field through it was changing. And if they hadn't been wrapped on the same ring, Faraday may have noticed that the two coils repel each other when the current is induced due to the interaction of their magnetic fields. This is the same thing that is happening with the aluminium plate, except we're using alternating current to create a continually changing magnetic field. This induces an alternating current in the plate, producing an opposing magnetic field which levitates the disk.
An atom is mostly empty space, but empty space is mostly not empty. The reason it looks empty is because electrons and photons don't interact with the stuff that is there, quark and gluon field fluctuations. It actually takes energy to clear out space and make a true 'empty' vacuum. This seems incredibly counter-intuitive but we can make an analogy to a permanent magnet. When at low energies, like at room temperature, there is a magnetic field around the magnet due to the alignment of all the magnetic moments of the atoms. But if you add some energy to it by heating it, the particles gain thermal energy, which above the Curie temperature makes their magnetic moments randomly oriented and hence destroying the magnetic field. So in this case energy is needed to clear out the field, just as in the quantum vacuum. Special thanks to Professor Derek Leinweber, find out more about his research here:
The physics behind Kelvin's Thunderstorm explained. No, it is not a practical way of generating electricity, which is why we use turbines at hydro stations. This video goes into more detail about the phenomenon demonstrated in this Hunger Games collab video:
Is the future of the universe already determined? Vsauce tackles What is Random? : Special Thanks to: Prof Stephen Bartlett, Prof Phil Moriarty, Prof Andrea Morello, Prof Tim Bedding, Prof Michio Kaku, A/Prof Alex Argyros, Henry Reich, Vanessa Hill, Dianna Cowern, George Ruiz and Mystery Cat. Views expressed in this video are not necessarily those of the amazing experts listed above but their advice was invaluable in making this video. Quantum simulation by PhET: Music by Jake Chudnow: Amarante Music: DNA animations by Space animations by NASA Topic inspired by The Information - a history, a theory, a flood by James Gleick Filmed on location at the University of Sydney, Washington DC and LA
Stained glass is thicker at the bottom - so is it a liquid? Earth's mantle enables plate tectonics, so is it a liquid? Check out Audible: Sign up for the mailing list: Pitch drop experiment: Thanks to Meg Rosenburg for scripting and animation, Raquel Nuno for filming and Aaron White for script consultation.
When pressure is applied to ice, its melting point is reduced so it turns to water. When the pressure is removed, however, it turns back into ice. This process is called 'regelation.' Big thanks to Art of Ice Sculptures who donated the beautiful block of ice.
Raw interviews: The question has arisen often enough that I thought I'd answer it. If you hold views that are consistent with the majority of the population, does that make you stupid? I don't think so. Science has uncovered a lot of counterintuitive things about the universe, so it's unsurprising that non-scientists hold beliefs inconsistent with science. But when we teach, we must take into account what the learners know, including their incorrect knowledge. That is the reason a lot of Veritasium videos start with the misconceptions. Want to read my PhD? You can download the full text here: .pdf
Microwave grape plasma: Northern Lights: Nanodiamonds in candle flames: Relight Candle Trick: Is a flame really a plasma? Well it depends on your definition of plasma, but there are certainly ions in a flame, formed as molecules collide with each other at high speed, sometimes knocking electrons off of their atoms. Special thanks to the Palais de la Decouverte for helping me perform this experiment. Using tens of thousands of volts on two metal plates, we created a strong electric field around the plasma. This pulled positive ions in one direction and negative ions in the other direction elongating the flame horizontally and causing it to flicker like a papillon (butterfly). Then we showed that much longer sparks can be made through the flame than through air since the ions increase the conductivity.
Huge thanks to the Royal Institution, Professor Frank James, and Katie Atmore for filming. For the Sixty Symbols version of this experiment click Michael Faraday created the first electric generator in 1831 using a coil of wire and a permanent magnet. When the magnet was moved relative to the coil, current was induced in the coil. A similar experiment can be performed with a copper tube and a magnet. Although copper is not magnetic, it is a conductor. As the magnet falls through the pipe, the magnetic field changes over different sections of the pipe. This induces swirling currents (called eddy currents), which create a magetic field that opposes the motion of the magnet. This means work must be done to move the magnet through the pipe. This work generates the electrical energy, which is then dissipated as thermal energy in the pipe. The same basic principle is used to generate electricity throughout the world: moving a magnet inside copper coils. Experiments A Cappella Where Did The Earth Come From The Coastline Paradox Microwave Grape Plasma Music by Kevin McLeod () Sneaky Snitch and Danse Macabre
Complete unedited interviews: Trees can weigh hundreds or even thousands of tons, but where do they get this mass from? A few common answers are: the soil, water, and sunlight. But the truth is the vast majority of a dry tree's mass comes from the air - it originated as carbon dioxide
Is punishment or reward more effective as feedback? Do new medical treatments really work? What about streaks in sport? Without considering regression to the mean, we are prone to making significant errors. Check out Audible.com: Filmed at Perimeter Institute: Is punishment or reward more effective for helping people learn. A lot of people would say different incentives motivate different people, or in different circumstances, but in psychology there is a sizable body of evidence that in order to learn skills, positive feedback is more effective. This fining has been verified not just with humans, but also with other species. It was strange then that after Daniel Kahneman discussed this research with Israeli fighter pilot instructors that he was met with resistance. They found the opposite was true: when they reprimanded a cadet for performing poorly, he invariably improved, but if they praised a cadet for an excellent performance, the next attempt was not as good. In order to solve this apparent contradiction we first need to understand regression to the mean. Teacher study: Rugby player study:
Epigenetics means women have different active x-chromosomes in different cells. Animation courtesy of Music by Amarante: Animation: Etsuko Uno Art and Technical Direction: Drew Berry Sound Design: Francois Tetaz & Emma Bortignon Scientific Consultation: Marnie Blewitt Courtesy of Walter and Eliza Hall Institute of Medical Research: When a female embryo is four days old it consists of just 100 cells. At this point the x-chromosome from Mom and the one from Dad are both active. But in order for proper development to occur, one of the x chromosomes must be switched off. Through a tiny molecular battle within each cell, one of the x-chromosomes wins and remains active while the loser is deactivated. This is done by wrapping the DNA tighter around proteins, modifying histone tails, and DNA methylation - molecular markers to indicate this DNA should not be read. What's surprising is that it's pretty random which x chromosome wins - sometimes it's Mom's and sometimes it's Dad's. So when a female is just 100 cells big, her cells have a mix of active x-chromosomes, some from Mom and some from Dad.
The Salton Sea is the largest body of water in California, home to the second most diverse group of birds in America and it exists by accident. Another great video on the Salton Sea: I used archive from this video. Music by Kevin MacLeod, ‘Mirage’, ‘Hyperfun’, ‘Marty Gots a Plan’, ‘Past the Edge’
Many videos on YouTube show water freezing almost instantaneously. This video shows you how to replicate the experiment and it explains how the phenomenon works. Molecular illustrations are courtesy of: PhET Interactive Simulations University of Colorado .
Who on Earth is exposed to the most ionizing radiation? Check out Audible: I'm filming a documentary for TV about how Uranium and radioactivity have shaped the modern world. It will be broadcast in mid-2015, details to come. The filming took me to the most radioactive places on Earth (and some places, which surprisingly aren't as radioactive as you'd think). Chernobyl and Fukushima were incredible to see as they present post-apocalyptic landscapes. I also visited nuclear power plants, research reactors, Marie Curie's institute, Einstein's apartment, nuclear medicine areas of hospitals, uranium mines, nuclear bomb sites, and interviewed numerous experts. Notes about measuring radiation: Sieverts are a measure of 'effective dose' - that means they measure the biological impact of the energy transferred to tissues from radiation. Obviously I owe a debt to the fantastic chart made by xkcd, which inspired my visual approach to this video. DOSES MAY VARY The level of radiation varies widely around the world depending mainly on altitude and geology (excluding nuclear accidents). Estimates of particular doses also vary. All numbers reported in this video should be taken as order of magnitude only. The most contentious claim may be that smokers receive the highest dose of ionizing radiation. This is not a whole body dose, but a dose to the lungs as specified in the video. References are here: Special thanks to: Physics Girl: MinutePhysics: Natalie Tran: Bionerd23: Nigel and Helen for feedback on earlier drafts of this video. Music is Stale Mate
Can we see things travelling faster than light? Check out Audible: Music by Amarante One Last Thing Awesome animations by Thanks to Prof. Geraint Lewis for input on earlier drafts of this video. The expanding universe is a complicated place. During inflation the universe expanded faster than light, but that's something that actually happens all the time, it's happening right now. This doesn't violate Einstein's theory of relativity since nothing is moving through space faster than light, it's just that space itself is expanding such that far away objects are receding rapidly from each other. Common sense would dictate that objects moving away from us faster than light should be invisible, but they aren't. This is because light can travel from regions of space which are superluminal relative to us into regions that are subluminal. So our observable universe is bigger than our Hubble sphere - it's limited by the particle horizon, the distance light could travel to us since the beginning of time as we know it.
Lift is an important concept, not only in flying but also in sailing. This week I'm talking to Olympic Sailor, Hunter Lowden. But before I get to the physics of sailing I thought I would explain lift since it's generally poorly understood. minutephysics 1veritasium efit30 appchat erikaanear whoisjimmy numberphile Music by Nathaniel Schroeder youtube: myspace:
Silicone oil droplets provide a physical realization of pilot wave theories. Check out Smarter Every Day: Support Veritasium on Patreon: Huge thanks to: Dr. Stephane Perrard, Dr Matthieu Labousse, Pr Emmanuel Fort, Pr Yves Couder and their group site Prof. John Bush: Dr. Daniel Harris Prof. Stephen Bartlett Looking Glass Universe: Workgroup Bohemian Mechanics: Filmed by Raquel Nuno Thanks to Patreon supporters: Nathan Hansen, Bryan Baker, Donal Botkin, Tony Fadell, Saeed Alghamdi Thanks to Google Making and Science for helping me pursue my sciencegoals. If you want to try this experiment, instructions are here: link.springer.com/article/10.1007/s12650-016-0383-5 The standard theory of quantum mechanics leaves a bit to be desired. As Richard Feynman put it, I think I can safely say that no one understands quantum mechanics. This is because observations of experiments have led us to a theory that contradicts common sense. The wave function contains all the information that is knowable about a particle, yet it can only be used to calculate probabilities of where a particle will likely turn up. It can't give us an actual account of where the particle went or where it will be at some later time. Some have suggested that this theory is incomplete. Maybe something is going on beneath the radar of standard quantum theory and somehow producing the appearance of randomness and uncertainty without actually being random or uncertain. Theories of this sort are called hidden variable theories because they propose entities that aren't observable. One such theory is pilot wave theory, first proposed by de Broglie, but later developed by Bohm. The idea here is that a particle oscillates, creating a wave. It then interacts with the wave and this complex interaction determines its motion. Experiments using silicone oil droplets on a vibrating bath provide a remarkable physical realization of pilot wave theories. They give us a physical picture of what the quantum world might look like if this is what's going on - and this theory is still deterministic. The particle is never in two places at once and there is no randomness. Edited by Robert Dahlem Sound design by A Shell in the Pit
Why is there a bright spot behind spherical objects? Be the first to find out about new projects: Filmed by Nathan Watkins and Raquel Nuno, animation by Meg Rosenburg. Music by Kevin MacLeod, 'Scissors' 'Mirage' ' Marty Gots a Plan'. Special thanks to Laura Vican for helping with the experiment. References: Why Toast Lands Jelly-side Down: Zen and the Art of Physics Demonstrations By Robert Ehrlich
Whenever an object spins through the air it experiences a 'Magnus Force' due to friction between the air and the object's surface. This force was originally identified while studying the trajectories of cannon balls (though earlier observations of this effect exist). The Magnus force is essential in most ball sports including golf, cricket, tennis, and baseball. At the end the ball demonstrations were conducted with a 100 mm diam polystyrene ball and the launcher was made by bending a long, thin, aluminum rod and bolting the ends to a block of wood as a handle. Music was provided by Kevin McLeod (incompetech.com) Scissors and a stock clip from FCP.
What happens when you decrease the pressure around a liquid? It boils. Water boils at room temperature once the pressure is low enough. What is interesting is that this decreases the temperature of the liquid. The fastest molecules escape, leaving the slower ones behind. Using this trick with liquid nitrogen, it is possible to create solid nitrogen at a temperature of -210C. We then poured the solid and liquid nitrogen mixture onto a tray of water. The surface of the water became so cold that CO2 solidified out of the atmosphere on its surface. Then, since CO2 does not pass through the liquid phase at atmospheric pressure, it was propelled on the water surface by jets of gas as it sublimed. Huge thanks to the Palais de la Decouverte. Music by Kevin MacLeod of Incompetech.com (Mirage)
There seems to be confusion about what radiation is and where it comes from. Many people believe it is the radiation that comes directly from nuclear power plants that poses a threat to public safety. In fact it is the radioactive atoms, which can escape in the event of an explosion, that pose a safety risk. They can be scattered by the wind over hundreds of kilometres. Then they may be ingested or breathed in. If they release radiation at this point, it is damaging to the body's molecules and cells because the radiation is delivered directly to tissues.
Hope this was worth the wait! So many people helped with this video: Prof John Sperry, Hank Green, Henry Reich, CGP Grey, Prof Poliakoff, my mum filmed for me in beautiful Stanley Park and Jen S helped with the fourth version of the script. Prof John Sperry Hank Green (SciShow) Henry Reich (minutephysics) CGP Grey Prof Poliakoff (Periodic Videos) Also thanks to the Palais de la Decouverte - they helped me with the whole vacuum pump setup in Paris. No, I could not actually suck water up 10m - I did about 4m, but the vacuum pump was easily able to do it and I saw spontaneous boiling on all of our various trials. Footage from this may end up on 2Veritasium. Trees create immense negative pressures of 10's of atmospheres by evaporating water from nanoscale pores, sucking water up 100m in a state where it should be boiling but can't because the perfect xylem tubes contain no air bubbles, just so that most of it can evaporate in the process of absorbing a couple molecules of carbon dioxide. Now I didn't mention the cohesion of water (that it sticks to itself well) but this is implicit in the description of negative pressure, strong surface tension etc.
Are you heaviest at night before you go to bed and lightest in the morning? I tried to tease out the factors to figure out what really causes weight gain and loss during the day, and what causes daily weight fluctuations.
Check out the original double slit experiment: - oh, and for the sun to be seen as single photons, you would have to be ~1000 light years away, so well past Pluto. For clarification on this video, please see: What would you see if you were drifting through space, looking back at the sun? Well its light intensity would decrease as the inverse square of distance from the sun. And you would imagine the intensity would decrease smoothly, asymptotically approaching zero. But this is not what happens. If you had sensitive enough eyes, like frogs' eyes, you would find that at some point the sun would start to flicker. You would see flashes of light separated by complete darkness. And as you drift further from the sun, what's strange is that these flashes do not decrease in brightness, but they do become less frequent. That's because light comes in lumps, called quanta or photons, which are indivisible. So if you try to spread light out very thinly, you reach a point where there are only single bits of light reaching an observer's eye at any given time. I should acknowledge the book The Fabric of Reality by David Deutsch, which contains a similar story about a frog and a torch. It inspired me to make this film. Thanks also to MinutePhysics for reviewing earlier drafts and suggesting I make it more ridiculous.
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
Explanations for Follow me on twitter: or Instagram: or Facebook: 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.
Used in everything from bullet-proof vests to the walls of the Pentagon, polyurea's strength comes from its long-chain molecules. Check out How Ridiculous: Snatoms magnetic molecules: Veritasium on Patreon: Special thanks to South Bay Line-X: Thanks to Patreon supporters: Nathan Hansen, Bryan Baker, Donal Botkin, Tony Fadell, Saeed Alghamdi Filmed by Prashanth Venkataramanujam SFX by A Shell in the Pit
Why does time appear to speed up as we get older? Can we slow it down? Thanks to the National Geographic Channel for sponsoring this video! The new season of Brain Games starts Sunday, February 14th at 9/8c - Brain Games is an Emmy-nominated TV series that explores the inner workings of the human mind through experiments and interactive games. Did you know it's estimated that you have more than a dozen senses in addition to the standard five? One of those is a sense of time or chronoception. Tune in to the new season of Brain Games to learn about all of your senses, and more, starting Sunday, February 14 at 9/8c References: Ageing and duration judgement: Nerve conduction velocity slowing with age: Experiments with rats suggest time perception is distributed across brain: Time perception with repeated stimuli: Energy usage in brain with age: Time perception in moments of fear / danger: Attention’s relation to time perception and recollection of perceived time:
Learned helplessness can prevent people from achieving their goals, something I've experienced first hand. Check out Audible: More walk and talk videos:
On a stream of water you can levitate light balls of all sizes and even disks and cylinders. The mechanism is not the Bernoulli effect. Want to make this at home? My friend Blake from InnoVinci emailed me with a cool idea for a video and footage of levitating balls in water streams. Initially it was tough to explain the physics of what was going on. The standard Bernoulli effect relies on the object being completely immersed in the upward-flowing fluid. But in this case the water seems to form a single stream around the object and it's deflected away and down from the stream. By Newton's third law, the force on the water by the ball is equal and opposite to the force of the water back on the ball, pushing it up into the stream. There is a stable equilibrium position because if the ball moves into the stream, it cuts off the water going over the ball so it drifts out. If it drifts out too far, then lots of water passes over the ball, pushing it back into the stream. Special thanks to Patreon Supporters: Tony Fadell, Donal Botkin, Jeff Straathof, Zach Mueller, Ron Neal, Nathan Hansen Support Veritasium on Patreon: Filmed by Raquel Nuno Slow motion by Hollywood Special Ops Music from Epidemic Sound Colored Spirals 3 Magnified X 3 In Orbit 2 ExperiMental 1