Aren't there 2 forces at play though? The -200c liquid oxygen will insta-freeze whatever is burning coating it with ice and some solidified C02, which along with the massive cooling will inhibit combustion. If there isn't much fuel to burn, it'll quickly go out quickly. At least play the devil's advocate. A lit match dropped into liquid oxygen would burn very well, for a very short period of time then go out. There would be no explosion. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-1kLsNRPiqco.html
@@JRemy-rz4rr you've got a good point but i'd argue that it actually depends on the size of the fire in that video you linked there is more liquid oxigen than wood to burn so the cold oxigen overcomes the matche's heat in a big fire there is a lot more wood and therefore more fire so throwing a cup of liquid oxigen in a fire would result in the oxigen boiling making it expand rapidly or what you would call an explosion
Clearly, even as you point out, there is an interesting discussion to be had there. Instead, the question was dismissed frivolously with one word. If it were that frivolous, it wouldn't have been asked.
1. So funny to see a celebration of 500K followers when you're sitting north of 9M. 2. A short description of the expansion of the universe that brings it all home for me. So many thanks.
Re: The blue sky, you're right, but you also need to take into account human photoreceptors which are quite insensitive to violet (and wholly insensitive to ultraviolet thanks to our lenses), while being very green/yellow sensitive, biasing the long wavelengths even further in our perception. For animals like birds with UV receptors, the sky would look pale indigo, and for insects that lack red receptors, it'd be downright violet. [Source: me, a visual ecologist]
@@ritwikbasak4960 Correcting the previous comment, the short wavelength, "blue" is the one that is scattered more than red light. At sunsets you see more red because you have a direct line of sight, which in part means a bigger trayectory for light, and in the longer trip, blue light is scattered more, so you perceive light with less blue, hence, red. It is a little more complicated than that but I hope to have helped.
Watching this again in 2021 is pretty funny. You have a luscious black mane, you have 20 times less subscribers and you have no idea how successful this channel will become! Keep up the sterling work!
Here's a movie idea. the year 3042, young Theodore C. Columbus sets off on a journey to prove that the universe is round. When he arrives at his destination, he finds himself on Earth 1550 years earlier due to space-time navigating errors. Now how does he get back home?
@Stewart I watched Leonard Susskind's course on cosmology (it's on RU-vid) And in Lecture 3, you examine the 3 possible shapes of the universe: flat, spherical, and hyperbolic. The only way to explain it is General Relativity, so I hope you know the general idea. Since we live in flat space, if you have a shape, a triangle for example, it's edges would be straight. But if you that triangle in curved space, the geometry itself is curved. Flat doesn't mean 2-dimensional: it means no curvature. The universe did expand in a sphere, but the space is flat.
500 000 four years ago, Thank you for not going away for all those years.. I have been watching your videos for years and I really appreciated you for all this time. Do not stop being amazing and infinitely interesting and fascinating! I think it is amazing that you went through so much and you still make those great videos. Love from Bulgaria!
I have probably a very stupid question... why does water doesn't burn? it's molecule is H2O meaning it is made from hidrogen that is very flamable and Oxigen needed in order to make fire. What is the diference between combustion and the process of evaporation. Do water at very very high temperatures becomes flamable? like saying throwing water to the sun?
there aren't stupid questions, just questions that make us feel stupid. Fire is the exothermic(to give off heat) result of a chemical reaction called (rapid) oxidation, which basically means to add an oxidizer (it is more complicated than that but it could take a while to explain that too) the most common being oxygen. I believe (I may be wrong) water simply would not accept more oxygen as its intramolecular bonds (the way the individual hydrogen and oxygens connect) are too strong to be broken by fire to create the 'opening' for more oxygen, to do that you would need a lot of energy... which is just what our sun has!! So to answer that question the sun will split the water to hydrogen and oxygen then burn the hydrogen, but the water itself is not flammable. water is kind of like burnt hydrogen and you can't burn things that have already been burnt hence back burning. (hope i did not lose you with the science)
not quite... combustion is a form of oxidation but the rest is wrong. its not that you need free atoms (which i cant comprehend how a molecule can have free atoms, did you mean electrons?) but the molecule needs to accept the oxygen atom. its really quite complicated after years of chemistry your question made me think. maybe Veritasium could do a video on it
innocentfir3 Yeah I mean electrons sorry. And that was a way better answer that some people have given me "because is wet, duh" and then i give my suggestion that they should bath in gasoline
lol. it is very interesting i would definitely like a video on this. i have asked everyone the same question now, no one can comprehend it i had a response "water doesn't burn because it is water, like water can't burn it is obvious"
Veritasium. I love your videos! Though, I feel I must remind you that there exist interpretations of Quantum Mechanics which are deterministic, so they don't include randomness. I'm specifically referring to The Many Worlds Interpretation and Bohm's Interpretations. These interpretations are much more epidemiologically satisfying because they do not invoke bizarre wave-function collapse scenarios and don't make reference to vague "observation" processes. In these interpretations, the role of randomness is replaced by self-locating uncertainties and uncertainty in initial conditions. Great Video. Best of luck.
+Bryon Pavlacka True, the theories are out there, and until we can devise an experiment to test which one it is, we will never know. But the many worlds interpretation still is non-deterministic because you can't predict in which universe you'll end up, even if you knew everything. And the hidden variables hypothesis is contradicted by the Bell's inequalities.
I did a detailed video about why is the sky blue on my channel. While I was watching it, this video came up in suggestion. So I thought to leave a comment about the same. And this one has a superb ending! A wild Michael appears haha :)
I think you completely missed the question of the blackhole. We all know it's imposible to escape a blackhole, even the commenter who asked the question. What he really meant was if you could find a way to travel faster than light speed (say invent an alcubierre drive) let yourself fall past the event horizon of a supermassive blackhole (so as to have enough time to escape before being torn apart) and the turn on your engine and win over the escape velocity of the blackhole and escape the event horizon. what would such event look like to you and to an outside observer.
From what i understand, for you: you would, as he said in the video, be sucked in faster because your time slows down, and you would instantly be sucked into the singularity. If you could somehow survive, the black hole would instantly evaporate, witch in reality would be a long, long time, as your time is extremely slow. For the observer, he would never see you enter, rather see you red-shift out until you are no longer visible, then would have to wait for the black holes inevitable demise to see you again.
An observer wouldnt notice because by the time u have been there a few seconds, the universe is pretty much over, the black hole has already evaporated by hawking radiation and the observer died 1x10^75 years ago... Moral of the story? Stay away from black holes...
Well, we also know that you can't divide by zero... But what if we could find a way to divide numbers by zero - what would be the result of dividing one by zero? I guess it would be THE SAME result you get by escaping a black hole (because ... can you prove otherwise?). In my opinion the scientific answer for this question is this: if you're asking a "what if" question, you're looking for a conclusion for the implication for which you provide the premise - but if the premise is well known to be untrue (impossible), then the evaluation of such an implication is always true - regardless of the conclusion. So whatever answer you can imagine is true. And scientifically useless.
Even if you were able to actually build an Alcubierre drive (which while the maths are working out remains to be proven; nothing in our known universe can generate the necessary negative energy potential, but that may change in the future...), it would be impossible to escape the black hole once you passed the event horizon, because the tidal forces would have torn you and your ship to an extremely long string of charged particles long before you actually reached the event horizon. Eventually even what we know as baryonic matter would cease to exist, as the tidal forces would eventually surpass the atomic force, splitting atoms into elementary particles, and then what comes next we have no idea, as it would be described by a theory of quantum gravity that does not exist at the moment. Theoretically, if you were heading into an extremely large (the larger the black hole the lesser the gravitational gradient, and the tidal forces) and rapidly spinning black hole, your Alcubierre drive in theory COULD get you out of it, provided you were still able to fire it up inside the event horizon and provided you were able to generate enough energy to surpass the gravitational field of the singularity. The trick to the Alcubierre drive is that it does not actually generate thrust, or move you through space. Instead it deforms the space around you by compressing space in front and expanding space behind. It doesn't move you, it moves the entire patch of space contained in the field, including your own gravity, kind of like a cut and paste. Inside an Alcubierre field you are always in free-fall, the only actual relativistic effect occurs at the boundary of the bubble, and is by definition a zero-sum (the contracting field has to balance the expanding field). This is what confuses a lot of people, arguing that it breaks causality, while it really doesn't. The Lorentz transforms don't apply because the ship is at rest in relation to the spacetime within the bubble. Using the Alcubierre metric, it has been determined that Alpha Centauri could be reached in 14 days of ship travel time with a field equivalent to 188G. The main problem is that it requires negative energy from either "exotic" matter (matter we have not yet discovered, if it exists), or derived from the Casimir vacuum effect in an arrangement of parallel plates. NASA has done some experiments in this regard but results were inconclusive and the idea was shelved for now at least. There is a page about it on the NASA website. You would need to generate a warp field in G's higher than the gravity the black hole exerts on you at your current location. If you were able to generate the necessary energy potentials, and if physics predictions hold true inside a black hole, then YES, you could escape from a black hole with an Alcubierre drive. But let's just say that is a lot of ifs, and for the time being it is more of the realm of science fiction. We haven't even ever directly observed a black hole as of yet, we only know they exist because the maths tell us they do, and because we can observe the gravity they generate, and the ionization of gas matter swirling into it.
Killer97 Oh, if only there were... reminds me of the author Terry Pratchette a bit...now there's a man who created gods who are a whole lot of fun to believe in
chargecloud How can you know? My friend, I believe you're miles off the point. Even the Bible reminds us multiple times of how our extremely inferior intellect cannot even hope to understand what he does. According to the Bible, for all we know, God might just say "YOLO!!!".
martijn van weele So GOD says yolo sometimes in shaping the universe? that's the dumbest thing I've ever heard...at that moment, god is no longer god...for there is somethings he has no control over... in creating his own creation. -think...
2:00 The liquid oxygen would actually put out the fire. In a liquid state, the O2 is so cool, that it would extinguish most ignition points. And the density of the O2 would actually starve the combustion of its oxidizer, as it requires being in gaseous form to react with the hydrocarbons. It would be like pouring mud or clay on the fire. Smothering it and starving it of (gaseous) O2. This is like asking "if I placed a block of frozen hydrogen next to a solid block of oxygen ice, what would happen?" The answer is: "They would melt and dissipate without igniting."
Hey bro your video about the interference pattern in water was absolutely sweet watch and I too will try it in a larger scale at least once before i complete my school days
He means flat as in not connected to itself, space is 3 dimensional but on no side does it touch another side.. if that makes sense. Regardless we can only observe what we estimate to be a tiny fraction of the universe so we could be wrong. Space time is curved as it molds around gravity in a sense, which is why as you leave earths gravity (eg ISS) time actually slows - thats how gps works actually. Cosmic Background radiation exists everywhere as it originated from the big bang which is why it exists (and is observable) in every direction. We arnt in the center of a sphere only that what we can currently observe of the universe is limited by the speed of light - universe is 4ish billion years old so we have yet to see any of the universe further that 4ish billion light years away.
Ariel Lazovic It's not literally flat. A spherical universe would mean that if you went in one direction through the universe forever then you would eventually wind up where you started, just like you would on Earth. They say it's flat because if you went in one direction forever, you would never come back to where you started, LIKE on a flat, 2 dimensional plane. Its more like the universe has the spatial characteristics of something flat (without edges, spatially infinite), instead of having spatial characteristics of a sphere. I understand the confusion. When scientists say that space is flat, they never really explain what they mean which results in much confusion.
Clarke Grieve The universe is 13.8 billion years old and we can see 46 billion light years away because of the expansion of the universe. That gives the observable universe a diameter of 92 billion light years. Just thought I'd clear that up. :)Also, the issue of time dilation on the ISS has more to do with general relativity than the curvature of space.However, you could still say that the curvature of space is responsible for time dilation because of gravity's affect on light and how light is a universal constant and time is just another variable.
Well, as far as i know, the sky emits more violet and NOT blue. But we are not so good at looking at violet as we are at blue. So sky appears more blue than violet.
i think i simplified your explanation of lightspeed and galaxies so light gets emitted but there is double lightspeed for it to travel because both the sending and receiving galaxies are moving away
therandomofrandom well actually... the sun will of gone red giant, and of consumed the earth in a fiery blaze of glory. after this the sun will go brown dwarf and do whatever the heck it wants
Wait was that sarcasm? there would be an explosion if you pour liquid oxygen on a fire? I thought fire needed heat, oxygen and fuel to form, liquid oxygen is very cold, and as rule the triangle would not be complete, hence no fire. So how is this possible? As what I know, oxygen doesn't conduct heat very well so should the surface temperature be cold enough to put the fire out before the surface of the liquid oxygen can heat up and react. Perhaps it's because the oxygen prevents heat from spreading under the surface and as the surface doesn't cool enough and will start a chain reaction that would consume the oxygen into an explosion?
+John Lukeward WHY ARE THERE NOT MORE PEOPLE CONTESTING THIS! - I'm super duper shocked that Derek even got away with such a short, (no offense, but science) idiotic answer.
+E231986 I suppose people are just contented with a short answer these days. People likes to be spoon-fed with facts (and sometimes false opinions) and doesn't bother asking or find out themselves the accuracy of the said fact. If Derek (or someone else notable) says the moon is made of cheese, some people just trust the information is credible because some RU-vidr/celebrity just said so.
+John Lukeward The problem is that it isn't a very specific question. It leaves too many variables. For starters, lets assume the fire is on earth. This seems to be a given but follow me here. Earth is a (generally) warm place, and most places on earth are very far from the temperature of liquid oxygen. This is amplified by the fact that the hypothetical oxygen is being thrown on a hypothetical fire, which are (usually) very hot. According to the laws of thermodynamics, these factors would cause the oxygen to warm up very fast, possibly evaporating before it hit the fire (still explosive though). Take this for example: If a drop of liquid oxygen fell onto your arm, it would evaporate very quickly without much damage to the surrounding tissue. This is because you are large and warm and the oxygen is minuscule and cold, causing very fast heat exchange. There are a lot of other unspecified variables that could change the outcome, however. How big and how hot is the fire? We talking match head or forest inferno? What material is being burned? These factors could produce a massive range of radiated heat given off by the fire. How much liquid oxygen is there? What *specific* temperature is the liquid oxygen? For example, *liquid* water could be anywhere from 1 degree to 99 degrees Celsius. This could mean the difference between a temperatures that are life-sustaining and inhospitable. What is the spread of the liquid oxygen when it was thrown? Hypothetically, it is possible that with a *small* fire and *a lot* of cold liquid oxygen, the fire would be put out. However, in the majority of these cases, it would likely happen as Derek explained, *kaboom*. So there's your answer, if you want it.
A Strange Tree Thank you for a well-explained answer. I figured it it has something to do with the amount of liquid oxygen being put onto a small or large fire. Also, if it was done on earth at normal room temperature, the rate it is poured would affect the outcome, if it is poured too fast, it wouldn't react just in time to sustain the heat. If it is too slow it would just combust steadily. I suppose I realized that when you blow air onto a piece of blazing charcoal it would blaze even more, but if you blow too much air that it would become too cold to burn, then the fire goes out.
Does a telescope look into the past or future? And which ever it is, what happens if you put a huge mirror in the space and look at it using a really powerful telescope?
If you mean in space really far from Earth, the mirror would be receiving and reflecting light from the past (which is what you would see). How "old" the light is would depend on the distance of the mirror from the Earth.
Messedup Birdie No because the light has to travel from Earth to the very far away mirror, then it is reflected from the very far mirror all the way back to Earth. The light you are seeing has taken a long time to reach the mirror and be reflected (assuming that the mirror is lightyears away), therefore you will be seeing "old" light (images) from Earth's past. I hope this exaplanation is good enough
***** You're talking about the green flash. It's not rare and it's a common phenomena. You'd have to time it just right and look at the Sun when its exactly about to set on the horizon.
LMFAO omg 7:15 - 7:36 made me laugh so hard! love vsauce and you guys are amazing too ^^ (just started to watch you guys, and its very interesting, im loving it ^^)
"But he, like every other Atheist, has no respect for Christian beliefs." How hypocritical, weren't you complaining about generalization and discrimination. I'm an Atheist, I have lots of Christian friends, but you are just rediculous.
I suspect that Buzz is one of those christians that consider it a severe disrespectful insult to hold beliefs other than theirs and not proclaim the unwavering truth of christianity which is undermined by its own book. He's is so intolerant of Zoroastrianism, like all christians, that I'm afraid I cannot allow myself to be besmirched by his presence and other such arrogant holier-than-thou nonsense ;)
Hey Ver, I just wanted to point out that you said that the speed of space expanding, when it passes the speed of light, we will not be able to see anything non - local. Well, you disproved this in Misconceptions About the Universe and I think you should put an annotation or something on this video so people know it's different than what you say in this video.
No, he didn't disprove this. In Misconceptions Derek said [citation]: "If it (sphere) gets bigger faster than that light gets away, it once get into subluminal region of space". The key here is "IF". As the expansion keeps accelerating, it will eventually reach velocity, so much faster than light, that any object, more distant than our local cluster, will become invisible (not only invisible, but also inaccessible).
I think you gave a wrong answer to the question at 3:30. It's not only galaxies that are accelerating from each other. Everything is. If you reach the point where you can't see the light of other galaxies because they're moving faster than light, then you won't be able to see the light of your house as well.
LMAO... I love it when people say things about what happens on the inside of a black hole beyond the event horizon as if they know what happens when that's impossible to know. You're adorable!
WOW!!!!!! got as far as 0.03 sec. I have a 2014W 7.2Ch Sound system at home that can shake windows till they brake < Fact < I left it with the volume up ( Oooops ) from yesterday, I clicked on your video and well........ I think the most of Melbourne think i'm having a Party when in fact i'm going to : check my pulse / clean the shit out of my pants / shower / go for a hearing test / replace window and a kangaroo. Still love your video's LOL Your the best. Peace.
i remember when you released this video.. dude you are at 6.86M now.. amazing.. always enjoyed your videos. also smarter every day. two of my favorite channels.
If the universe is constantly expanding it must be getting larger and encompassing more area so there must be an area that isn't a part of the universe so what is the area outside of the universe like?
2:30 Technically the time until you reach the singularity from the event horizon depends on the size of the black hole. So if you wanna enjoy the inside of the black hole a bit longer, jump into a big one rather than a small one.
I don't think scientists should get Nobel prize but educators like you should... Making some complex theories simple and understandable, sharing the knowledge so that everyone can understand is a greatest part of humanity
lol yooooo Derek the way you just holler at Michael was awesome and the way he responded back like I got your back bro lol that Mr. fantastic topic didn't know that you and Michael or In cahoots
Great video! I feel that you are the only science RU-vidr that can thoroughly explain science phenomenon, probably because of you Ph.D and also because of the variety in your videos. Keep it up!
Even in art, painters going for a 'realistic' daytime blue sky don't use a supersaturated blue. I know from experience that the sky contains a lot of white, and the bright blue we see is actually a light shade of blue. :)
Can you explain WHY hot metal is glowing with red, orange, yellow, white and even blue, when hot, but NEVER with green, although red and blue seem to lay on the opposite sides of the spectra? Or maybe there is green, but is masked and just we do not see it?
Okay, the black hole question ...I have one too. After you entered the black hole and managed to get out. WHEN is it? How does time behave. Could it be possible, to enter a black hole today and leav it yesterday, cause of some randome time fluctuations happening behind the event horizon.
lol i was about to "nominate" you for vsauce4 but at the end of the video it looks like you guys already work together in someway, maybe the v in vsauce is for veritasium.... wait a second.... screw vsauce4, make a channel called "the v in vsauce". i love these kind of videos, im addicted to learning. best vice ever
Basically, inside a black hole's event horizon, it isn't just that the singularity's escape velocity exceeds c, it's that the singularity warps space in such a way that all possible paths in spacetime lead closer to the singularity.
Please make a video on string theory. Your videos are really good and simple to understand. If you uploaded these 15 year before I would have continued physical science in my graduation.
I know this is a very old video, but do you have an email or some sort of communication channel where I can ask some questions? I love your videos and it really makes me think. I have random questions, crazy questions, but just not sure who to even ask!
It's crazy to see this video for the first time now, when you have 9.56 million subscribers and you were celebrating 500 thousand at the time. Well done Derek!
In cosmology, when people say the universe is expanding at an accelerated rate, is that the same as saying that (galaxies, etc) aren't slowing each other down as much due to an increasing distance from one another? That is to say, does an object that is at escape velocity from another object have 0 effect on the first object? Is Dark Matter/Dark Energy necessary to explain the lessening influence matter exerts on other matter at an increasing distance? Is "Things aren't slowing each other down as much as they once did" a more accurate explanation of what's going on? Or is the speed of "acceleration" we observe more than you would calculate as being the result of a "letting up on the brakes"?
If you were to say fly faster than light would everything be frozen as you were flying or would you see everything go much faster, or would it be normal movement? I think it is the former. Thanks.
Regarding that thing you said about how at some point we wouldn't be able to detect certain things that we do now in space: how do we know that there isn't more to what we see now, we just can't see it because of those same reasons?
Within the limits of our telescopes, we can now see the entire timeline of the big bang expansion back to the earliest feature of the universe that can be seen in light.......the "Surface of Last Scattering" of the Cosmic Microwave Background radiation. That's the earliest thing we can see in light, and it's opaque to light. So even with improved telescopes, we can never see through the Scattering Surface to any earlier time in the big bang expansion. There's just no earlier time to see in light. Although in the future we'll be able to see closer objects with better telescopes than we can see now, we'll never see any more of the timeline of the universe. Light photons which are beyond the Hubble Sphere (in transluminal space) cannot ever get to the earth to be observed. Even now, the Surface of Last Scattering is at a distance of about 46 billion light years, and is far beyond the Hubble Sphere. So the light it's emitting today can never be seen at earth any time in the future. (The reason we can see the Scattering Surface in our telescopes today is because we're seeing photons which were emitted about 13.4 billion years ago when the universe was much smaller, and it was much closer to the earth.) In addition, as the expansion rate of the universe accelerates and the Hubble Constant increases, the size of the Hubble Sphere will contract, and more and more of today's observable universe will recede behind the light horizon.
