Added: 3 years ago
From: ASKaPHYSICIST
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  • And what if there is a slightly large amount of mass on one side of the tunnel

  • Also you would be accelerating at approximately 9.8 m/s^2 you would be moving at extremely high speeds therefore possibly making you capable of "time travel"

  • @AllianceLeader1 no, there is no force that can accelerate you beyond the speed of light as your mass increases as you approach it

  • Ok so since heat is cause by molecular motion and there by having friction wouldnt you also heat up s you went just like space shuttles do when reentering the atmosphere?

  • @AllianceLeader1 probably You might also feel sick. Clearly I haven't considered everything here

  • Comment removed

  • Wait 4000 km an hour wouldn't that launch you into space like u jump in and ur going so fast that u shoot in to space

  • @MrWowman21 it would, if gravity wouldn't slow you down again. 

  • Your very nice at your videos, you make them simple, yet very educating. I was asking the same question one day before! And hope your doing fine :)

  • @yorkchr123 thanks, glad you like them :)

  • Like 2 ground portals

  • You don't look like a physicist. At least you know what your talking about.

  • @AluminumTiki I don't? How come?

  • Awesome video! One question though, assuming you have air in the tunnel wouldn't the pressure be enough to kill you at that depth?

  • @TorchonFire let me think ... yes, yes it would. And that would probably also mean that the friction isn't constant. Not sure what sort of oscillation that would give. It's not simple harmonic. Oh, dear.

  • by saying that there is no gravity in the center of the Earth is like violating Newton's inverse square law of gravity which states that g = m1 m2 G / d^2, when d^2 is zero, the gravity tends to infinity.

  • @ASSHOLELA Not really. What I am saying is that you have essentially equal gravitational attraction from both sides, which cancel each other out and you don't experience a force.

  • If this where a real scenario wouldn't you reach velocities that would kill you? Meaning just like entering the atmosphere you are moving so fast that the air would burn you up.

  • @DrShpilev well, no because from the start the air friction would slow you down and you would reach your terminal velocity. In entering the atmosphere, you're actually moving faster than your terminal velocity, because in space there is no air friction.

  • @ASKaPHYSICIST

    Good point. Thanks.

  • @DrShpilev You're welcome :)

  • OMG YOU ARE SUCH A NERD

  • Do you you think that harnessing that same effect in some way would enable ufo type travel?

  • @gabesolis89 you're asking me if throwing things through a hole in a planet could potentially fuel Unidentified Flying Objects? 8-[

  • @ASKaPHYSICIST If you had an object inside of a gravity cancelling field for instance the center of the earth, therefore floating, and manipulating the direction of travel through weakening or strengthing the cancelation effect on different sides. And if it where possible what would be the maximum velocity one would travel in that scenario?

  • P.S. I'm not being mean or trying to say you don't know what you are talking about. I think you are very knowledgeable and I like your videos! I'm just pointing out a slight discrepancy in fact. Keep making videos!

    Also, cheers from the U.S.

  • Also, interesting video. Thanks for taking the time to educate people!

  • You said one would be weightless because there were no forces acting upon you, but that's wrong. Forces in ALL directions are still acting upon the body, but are equalizing, hence the weightlessness. They don't actually "cancel out", the just are equal in their action upon the body. The forces still exist.

  • @planetrob555 I don't think that's what I said. Also thanks.

  • @ASKaPHYSICIST At 3:06, you say "there are no forces pulling you in any direction." That is false. The forces are still pulling you in their respective directions, but since they are pulling you in equal directions in supposed equal amounts, you reach equilibrium. The forces are still there, and they are still acting upon you. They don't disappear just because you reach an equilibrium point.

    Right?

  • @planetrob555 I appreciate the politeness of your objection and I see where you're coming from. However, if you really look into it, this is but a point about semantics. I could argue that it's actually the 'gravitational fields' that cancel out and thus that there are in deed no resulting 'gravitational forces' acting on him. In any case, both ways of putting it are wrong since the explanation of gravity lies in the curvature of space-time and the force explanation is but a simplified model

  • @ASKaPHYSICIST OK, I see what you mean. And yes, it's mostly semantics.

    Thanks for engaging in learned conversation! I appreciate the responses. Again, cheers from the U.S., Kentucky to be exact. Where do you call home?

    Looking forward to more videos.

    ....rob

  • @planetrob555 The pleasure was all mine :) I live in the UK, Wales to be precise

  • what is erath

  • @law23haha huh, someone actually read the description. Thanks.

  • If you go into that hole, you will be arrested for being a pedophile.

  • @1emanres Is there a reason for that or are you talking from experience?

  • Surely the air resistance (I'm assuming there would be some at the extremal points at least) would lead to retardation. This damping effect would lead to the person eventually ending at rest in the middle of the earth. I also believe that unless the person is a particle which sits directly in the centre of the tunnel, the person would end up resting against one of the walls (assuming the earth to be a perfectly uniform geoid)

    .

  • @rincewind869 did you watch the whole video??? Yes to your first question, No to the second. You only get to rest at the centre and there you'd have essentially zero gravity. The attraction to any wall would be minimal. Tipping you're toe against it would repel you ... unless your tunnel is very wide.

  • @ASKaPHYSICIST My bad, I did stop watching before the end. Nice conclusion. I do, however, still believe there would be attraction to a wall if the path followed was not perfectly centred.

  • @rincewind869 well, quite right, but the closer you get to a tunnel that goes straight through the centre, the less attraction you'd feel.

  • stickman abit dizzie?

  • @dudelolwot he'll be fine. 

  • Entropically, the novel idea from Jules Verne will never be possible or even feasible. If you mined a hole down 30 miles to the Mohorovicic discontinuity, two things would happen. First, you would die from the extreme temperatures and pressure, and no super-cooled machine could withstand these variables. Second, the pressure difference between the mantle and the hole you dug would cause the mantle to punch out and up. You would essentially create a man-made volcano.

  • @cagce3888 thanks for the warning.

  • You would actually be crushed by air pressure:p Much like being deep under water.

  • @fcdog555 you done the maths?

  • @ASKaPHYSICIST Well think about it. PV=nRT. The temp and the moles will increase dramatically will they not?

    with that, pressure will easily exceed 1atm. But I suppose it depends on the volume doesn't it.

    I'm still going to side with it crushing you, but if I find time, I shall do the math and I'll report back to you:)

  • @ASKaPHYSICIST the pressure doesn't really matter: 3000 kilometers free fall through atmopshere... Even guys from NASA would shit their pants about this kind of friction :D

  • I'm still going to JUMP in it!

  • I CAME UP WITH THIS BY MYSELF BEFORE I HEARD IT WOOOOOOH

  • @101796bg well done!

  • I've also heard that the earth's spin would actually make you ricochet from side to side in the hole. Would this be true?

  • @alderusdmc If the hole didn't go through the centre of rotation, yes, then you'd hit a wall. that is because the inside of the earth moves less quickly then the outside.

  • I used gauss' law for gravity to get an equation for the acceleration inside the earth, then solved the differential equation you get by setting it equal to R'' (second derivative of distance from center with respect to time). I solving this I got a cosine function. Solving for the period of oscillation I got:

    T = √( 3π / (Gρ))

    Where G is the gravitational constant and rho is the density.

    Your thoughts?

  • @elfmotat If you send me your derivations, I'm happy to include them in the description and/or on an additional post on my website (if they are correct), giving yo credit of course.

  • @ASKaPHYSICIST I just sent you a PM.

  • @elfmotat thanks, I'm looking into it

  • You talk like a pilot.

  • small point on the side, because air resistance is a function of velocity and the gravitational force is slowing as shown, your speed would be significantly less than free fall speed (like a parachutist out of an airplane) once you reached the center. Your distance covered after reaching the center will be damped considerably more than shown in this video. I am sure it was an aesthetic choice, so count this as an aside. How far would you get from the center assuming STP? No more than 100 miles

  • foreign people  would appreciate more if you could speak a little bit slowlier...

  • @Robmick06 I'll try

  • If Asteroth were to throw a whales testicle at an old woman climbing out of a volcano, would that be considered a feasible cosmic phenomenon?

  • @DerFauxRitter I guess it's feasible, but a cosmic phenomenon it is not.

  • Is that how you really talk?

  • @ZZMann33 I'm afraid so.

  • My brother always told me that you would be crushed, now i can rub it in his face

  • @aprecon2012 well, he would be right in assuming that the air pressure would be greater at the centre of the tunnel. hmm, i kinda neglected that. Let me do a little calculation and get back to you before you rub it in. he might have a point.

  • @ASKaPHYSICIST Ok will do, thanks

  • Is it possible to do on moon ?

  • @StefanAxelWels Not sure, I don't know about it's interior. Practically speaking though, the answer is probably 'no' anyways'. It would take far too much energy to make a whole that deep.

  • @ASKaPHYSICIST Yep, you're probably right about the forces it takes but, one can in end send something happening to a counterattack previously on the other side and vice versa that is not hindered by the matter and it exists as infrared.

    Or will it not change at all, it do change it wawe link on earth upp and down and back in artifeciell clouds and back again through earth out to space ...Specially to sun (i think) about thunnels in all case then)

  • Ah. I change my question little, if the other was to strange. Do infrared wawes change the length wen it pass matter or wen do it change wawelength, this is what I really wanna know.

  • Could the earth really be hollow???

  • @kimcheolho probably not, no

  • You would starve before even getting to the center if you think about it.

  • because gravity is equal to zero in the middle of earth abd the earth spins why is not the earth hollow?

  • @datzfast and if it is hollow why is the earth not then growing larger with time?

  • @datzfast because earth started as a small rock (the center) which attracted other little rocks to create earth lol if it was hollow. there would be little gravity

  • @Lensk15 little gravity, ah that explanes hoe i can overcomr thr tiny forceof earths gravity by jumping

  • Super Genius.

  • How does it work to split an atom? Like they do in bombs. I would like to see a demonstration like this about it

  • nice webshow!

  • I heard that there's a 5th state of matter. Plasma, gas, liquid, solid, and the 5th one is (I don't know the name). But it brings and object behind solidification, which can only happen in areas of the Universe which go below Abolsute Zero temperature. Can anybody shed some light?

  • best. accent. ever.

  • The harmonic motion will not exactly be "simple". The accelerating force would not be linearly proportional to displacement: due to inverse square law (hmm.. but that's for point masses) and complications due to densities.

    SHM might be a close enough approximation, however. Comment?

  • @roshanram While he is within the surface of the earth, the force on the jumper actually would be linearly depended on his distance to to the centre, tending to zero as he reaches the centre and reaching a maximum as he reaches the surface. This is due to the forces in opposite directions cancelling out.

    If he goes further than the surface, the inverse square law would in deed kick in. I should have made this clearer.

  • Great video, learned a lot. Thank you!

  • hey man, i just recently ran into your videos after researching about a recent ufo siting in western canada 2 days ago, i journed thru all sorts of alien/cosmology related videos to learn what i can, and came across this and so i have this one question related to this video. very random tho lol. go to pretend mode and help me determine, theoretically,if we attached a durable elsatic source like a miracle bungee-chord lol, and

  • .. and were arguably able to make it with no interferance such as bumping into walls or anything, how would that effect the physics both ways during gravitational pull? would we bump some where on the other side of the earth's crust before dragged at a certain velocity back toward the hole? feel free to take it into as much detail as you want if you decide to make a video for this question, i do have a very open mind and LOVE learning anything i can. :)

  • Great video and series.

    What would happen if as he was falling he repeatedly farted out the expanding gases caused by the bacteria munching on the 4 burritos he ate at lunch... in exactly the opposite direction to his travel?

    Would these extra impulses be sufficient to enable him to reach the other side plus a bit, re-orient his buttocks to either the left or right after escaping the tunnel, and then land safely?

  • @PencilsAreAwesome it would help. But I think he would have to fart pretty hard to make up for all the friction from the air. That would be a lot of burritos.

  • gravit is a weak force.. ( so weak jedi can control it too ).:p

  • could a real tunnel be used to be the worlds fastest way to travel through the earth if we had the machines to do it and a elevator was made and the first time u did it u pop out the other side cuz Ur going so fast so it stops u there for no energy is used so its now the fastest way and cheapest way . also would the air on earth be pulled into it since all thing have mass there for gravity pulls mass so the air would be held in the center of the earth ????

  • Everything (and I mean everything) is trying to do simple harmonic motion around the center of the Earth. Takes about an hour and a half to get back. The problem: there is a massive traffic jam of particles all trying to do exactly the same darn thing.

    I don't recall seeing solutions in general relativity being discussed as simple harmonic oscillator solutions. Guess I have a bad education.

  • I got a question. With some of the deepest holes in the earth already the wind or air on the surface falls down into the hole almost creating sort of like a wind tunnel. If a tunnel were to be dug all the way through the earth wouldn't the air on eaither end be sucked into it creating the openings of the tunnel almost like a suction. And if so wouldn't air be sucked into the tunnel at tremendous speeds?

  • "Don't jump in"

    But it looks SOOO fun!

  • I dont think he would reach the surface on the other side as shown in the video. Wouldnt he decelerate and stop before reaching the surface and start falling back in again?

  • well, I commented on the friction.

  • Does it just depend on the velocity minus the friction?

  • I think you mean acceleration minus friction

    As you fall you accelerate due to gravitational force, but the force of friction opposes that force and reduces the acceleration.

    If you were in a vacuum, you'd fly all the way to the other side.

  • Since the current theory of gravity and our sciences in general seem to be somewhat infantile, I believe there are many flaws which would lead to misconceptions. In my opinion gravity is mass attracting mass, and gravity itself is something that attracts and repels quite evenly.

  • I really liked tthis video!!

  • when you come out the other side.. would you feel upside down?

  • Not any more upside down than a guy who got to the other side of the earth by plane.

  • haha

  • I read somewhere that there is a lot of nuclear radiation contained within the centre of the Earth too, and that if we dug a hole there, it would release this radiation into the atmosphere on the Earth's surface. Is this true?

  • That would be news to me. But as I said, it would be as good as impossible to actually get anywhere near to the centre of the earth so I wouldn't worry about that.

  • ASKaPHYSICIST: I have a question regarding this video. I now completely understand what would happen if you jump in a hole going through the center of the earth. My question is: what if on your drawing of the hole going through the earth, you moved the hole over to the left or right a bit, so the hole is not going through the center of the earth, but still to another point on the earth. What would happen then since there is none of the zero gravity stuff happening in the middle? Any ideas?

  • well, if you would picture standing infornt of such a hole you would see that it's not going straight down from your perspective. So I'd imagine if you jumped in, you would roll down towards the centre of the tunnel.

    However, if you'd find a way to eliminate all the friction between you and the tunnel wall, the same principles would apply.

  • We wouldn't see it but it is the way to go. Great subject.

  • I am thinking along the way of shipping containers in the future. It would save tons of fuel. Even if there where some risistance, to make it the rest of the way would be minimum energy. Let's say tunnel is on an angle even, at least the first half of the trip would be a free ride, but of course more than half the ride would be free. Much could be discussed on this subject, extract heating sources and lots more. :)

  • You have a point, but I think we're talking about a very distant future here. To date the holes we have dug in the earth are really quite insignificant in regards to it's overall size.

  • What you have just discussed may be perpetual motion I would think. If we made a tunnel and put a rocket shaped device carrying cargo fuel cost would be zero. Even a tunnel on an angle would do the same I would think, as long as the angle was tilted enough to get ya rolling?

  • Well, that is ignoring wind resistance as he said. It is not perpetual as friction is slowing you down and you do not move the same distance each time.

  • quite right ivnuzi, but if you've already made a tunnel through the earth, I guess you might as well seal it up and pump a vacuum in it.

  • Can I hire you for partys?

  • I'm flattered, but I've given up on being a stripper a long time ago.

  • what would happen if you traveled faster that the speed of light out side of the earths atmosphere would u start to get younger or stay the same age untill u reached the end of the universe or the beginning of the universe. :)

  • well, according to special relativity, we will never find out... it predicts that faster than light travle is impossible. More specifically it says that the speed of light is constant regardless how fast the light source is moving relative to you. This has effects such as time dilation, which causes time to slow down for you if you move near the speed of light relative to someone else. well, who knows maybe einsteinwas wrong.

  • @dannybong55567 (You wouldn't get younger. You would age exactly the same as if you were not travelling at the speed of light. However, because you are travelling at the speed of light, your frame of reference is different to that of a person standing still, therefore what would be 1 hour for you could be 100 years for someone who is standing still. Aging is a biological process therefore it would be the same. Yet when you travel at C, time slows down in respect to a still frame of reference.

  • why do you stop in the middle as time passes on? this doesnt consider the law of gravitational potential energy being converted into kinetic energy, because this would state that if u were to jump the same gravitational pottemtial enery u have at the top, would be converted to kinetic, and then back to gravitaational when u reach the last altitude or "moment of no gravity" and then thois procces would keep occuring over and over again. so why would u stop eventually in the middle?

  • Friction from the air ... as I explained.

  • its air resistance, u will eventually slow down, and then stop, and then ur fucked lol.

    we did this last week in physics 2, very fun (we didnt actually jump into a bottomless pit, but we did this theory)

  • Pardon my irrelevant question, but is your accent for real? Or are you really a native English speaker bunging it on for effect? LOL!

  • I wish. My english really sounds like that.

  • Comment removed

  • u sound like a pilot

  • On second thought, since atmospheric pressure is caused by gravitational pull, I'm not sure what would happen.

    The tunnel shape also becomes quite confusing here, as I'm not sure of what would happen to air currents with these weird gravitational effects.

    The air in the middle wouldn't weigh anything, and air further in would be lighter then normal, but I wonder if the colon of air from each side would still cause the pressure to be quite high anyways, and would the air circulate? Hmmmm.

  • No, no, I'd think you're right. The air from both sides of the tunnel would be pouring in wards, pressing on the centre. The waight of the air may increas as you go further down, but there should still be a greater push from above. You're right, i did not consider this. Well, I suppose you could take account of it with an appropriate pressure suite.

    btw, by 60m do you mean meters or miles? 60 meters doesnt seem like much

  • I haven't gone through the rest of the comments to see if this has been said before, but I noticed one thing you left out.

    In diving, 02 becomes toxic at around 60m below surface (700kPa).

    I never bothered to figure out the exact numbers, but at the center of the earth, the athmospheric pressure should be MUCH higher than that, meaning that you experience a seizure followed by death long before you reach the center.

    I'm also not sure of what the effects of that kind of pressure would have on you

  • I Want to try this,if we do this later in humanity,make some suits to dont bur of heat,IM A VOLONTER XD

  • I'll let you know when there's a place available.

  • First off great video. I saw something recently about the possibility of transport tunnels being dug through the earth. Not throught the centre, but on a certain angle (Im sorry I cant remember what the angle was.) The idea was that if you dug a tunnel at this angle and created a vacuum in it, you could use gravity to move you huge distances in a matter of seconds. Possible? or science fiction?

  • well, theoretically you could do it courself. Just digg a tunnel and put a vacuum tube in it.

    Practically, you'd need to make a very long tunnel to make this venture worthwhile. I don't think creating a vacuum in such a large volume is feasible and even if, who would want to travel with this thing knowing one might get stuck miles below the earth crust with no breathable atmosphere around.

    well, thats just my opinion. . I'm sure yod also need frictionless walls also

  • I thought the idea was impractical at best, but the documentary I saw made it seem at least feasable. I will try to find it and provide you with a link, but Ive been having severe computer problems recently, so I promise nothing. Will msg you if I find it.

  • I think i ve seen the show you mean. It was a funny thought, but I don't think any practicalities were considered.

    If I'm not mistaken they said the travel time through any tunnel through the earth, if we were in complete free fall, would always be the same.

  • Yes thats the one, id forgotten about the travel time being the same to any point, from any point. That indeed makes the concept look rather foolish. If the idea of building a stable tunnel through liquid rock wasnt foolish enough!

  • approx how long would it take for you to fall all the way through the earth?

  • h = 0.5gt^2 = 1.3*10^7

    t^2 = 2.6*10^6=root of 2.6 *1000 = 1600s = 266 minutes = 4 and a half hours xD

  • is that correct? :S

  • if i'm not mistakes, you're assuming g is constant, which is not the case. it gets slower as you fall. one would need to integrate to get the result. Sorry, but thanks for the effort.

  • very nice video good job i subscribed =]

  • question: on the first half of the trip is the acceleration constant, or, as you work toward the center does the fact that you have earth 'behind' you alter the magnitude of acceleration? i am thinking about the tradeoff between the decreasing distance between the stickman and the center of gravity and the fact that he is actually within the body attracting him...thanks for the video!

  • The gravitational acceleration is proportional to the gravitational force (as indicated by the blue arrows). so there is no acceleration at the centre (except for that due to friction). If you want to be precise, the acceleration is not constant at any point (although we usually treat it that way on the earth surface).

    you're welcome!

  • stickman's screams are horrendous....

  • what if someonecould travel the spped of light what would happen is it possible

  • Time would stand still for them and their length would contract to zero, theoretically. But sofar it seems that it's not possible.

  • adding on to the question what would happen when your going at the speed of light and then turner on a flashlight pointing in front of you

  • well, as i said, as you're travelling at the speed of light, you would not experience any passage of time. So you couldn't turn on a flash light.

    well, if you were accelerating towards the speed of ligh while having a flash light on, you would observe the light leaving the torch always at the speed of light, regardless of how quick you get. This is a result of time dilation however. An outside observer would also observe the speed of the light of the torch at that speed.

  • Comment removed

  • Okay so what would happen if you cut a giant tunnel through the MOON? That is certainly more plausible right? There would be less gravity and no air resistance. So what would happen if you jumped into it?

  • Well, the same principles apply. For zero friction, you would get simple harmonic motion.

  • could the earth be hollow ive heard somthing about that could it actually be hollow

  • i would say that is extremely unlikely. First of all, all geological evidence says otherwise, secondly i couldn't think of a reason why a planet would form in that shape. It's much more unstable then a solid sphere.

  • can you tell me is their a crystal that matches the earth core in this Universe ,I hear Mars has similar.?

  • sorry, what do you mean by crystal?

  • The core the centre of the earth is made of some kind of crystal ,and some research by a German Scientist found that the crystal found on our earth is similar to the one on Mars?wanted to know if you know about this theory?

  • Ok, just looked at something about that theory. Well, first of all you shouldn't think of crystal as in the nice stones we usually refer to as crystal. A crystaline material is a material with a ordered arrangement of atoms. If that structer is cocnsistent through out the material, we call it a single-crystal. So, there is a theroy that the earth has a single-crystal at its centre.

    I'm not sure how well established this theory is (obviously noone has ever seen the eareth's core).

  • can you explain lightyears, ex. how it works, and how fast and far is it.

  • I think I can, well, a light year is simply the distance that light in empty space would travel in a year. The distance travelled by light in one second is about 300000km. multiply this by the amount of seconds in a year and you get about 2600 times the distance of the earth to the sun.

  • i was just wondering if there is any way that if somewho you made the tunnel a vacum, erasing the friction from the air, and then coated the tunnel in copper and dropped a giant magnet in it, would you have unlimited electricity?

  • Excellent question. Unfortunatelly the answer is no, due to Lennz's law. The current induced in the metal due to the moving magnet would generate a magnetic field oppsing the motion of the magnet, hence slowing it down.

    A general rule of thumb in physcs: There is no such thing as a free lunch.

  • i cant watch the hole movie i no what happens but the voice makes me sick

  • Good video, is just as I thought :)

  • how about a tunnel in the moon?