Zero-G Experiments on Earth: The Bremen Drop Tower

[@andrewb1870]

it flies through the tube so smoothly, its great

[@JakeDownsWuzHere]

oddly satisfying

[@LexieAssassin]

Giggity...?

[@unvergebeneid]

+Jake Downs My thought exactly! 3:30 in case anyone needs that again :)

[@magellanicraincloud]

+SirWaffleOfSyrup photoshop a trampoline at the bottom then play the footage in reverse, then gif that.

[@LDRO]

Bipolar- Bear its soooo satisfying

[@OldBuford]

the way it travels perfectly straight is so satisfying. im sure the German engineers who designed it deem it "hinreichend" but im absolutely amazed.

[@Thomas_Bergel]

Bosco26726 To all non-german speakers: „hinreichend“ means „enough“

[@CleanPickleRelish]

More like adequate for passing I'd say

[@mikeehrmantraut7064]

Unglaubliche Perfektion

[@ingenium5831]

In a scientific context the translation "hinreichend" = "sufficient" would be more accurate (see "necessity and sufficiency" as terms in science) :-)

[@MrKakaofreak]

@@Thomas_Bergel I would say: barely enough! :D

[@keepXonXrockin]

I remember seeing the tower going past it on the autobahn when I was little... my mum always told that they drop bowling balls in there to learn about gravity :D

[@TheScords]

We have the same parents i guess...

[@cadenhood]

@@TheScords What a twist!

[@pulseluft]

Same with me but i still live in germany

[@jaimedelgado7529]

U guys call it "the pencil" dont u?!

[@A-G-F-]

Autobahn and free fall tower? You guys live in a place that loves speed

[@TomScottGo]

This video has an error: I oversimplified the calculations for freefall and ended up quantising them. Yes, the speed increases by 10m/s², but that doesn't mean it travels 10m in the first second. It'd travel 5m, then 15, then 25, and so on. Several physicists reviewing that script didn't notice the error, either! All corrections on this channel can be found at www.tomscott.com/corrections/

[@PeterPete]

Hi Tom - did you contact some of the physicists who reviewed your script to make them aware there was an error?

[@whtbobwntsbobget]

THE CORRECTION IS WRONG ALSO! You wrote 10m/s^(-2). You should've wrote 10m/s^2 or 10m×s^(-2).

[@joeols90]

@@whtbobwntsbobget That's a typo tho. Not really that big a deal, since it's obviously a typo.

[@matildastanford7019]

@@joeols90 g'day, any error is still an error, not about nitpicking, but the devil's in the details and any correction is invaluable. Hope you have a great day mate. ✌🙂👍

[@rsmith155]

NERD 😏

[@Ostsol]

Love the wonderfully low-tech deceleration system!

[@hxhuang9306]

Whilst it takes extreme effort to create on Earth the most common things in the universe (high vacuum, micro-gravity, etc)

[@CombraStudios]

Perfection is in simplicity

[@enzop177]

Legend Length I don't know if the human body can survive 50g of deceleration, but you never know until you try

[@paulzapodeanu9407]

There are race car drivers that have survived crashes at upwards of 200 G, so 50G is likely survivable not sure about how enjoyable it is though.

[@paulzapodeanu9407]

There are race car drivers that have survived crashes at upwards of 200 G, so 50G is likely survivable not sure about how enjoyable it is though.

[@TomScottGo]

And before anyone comments to complain: yes, I know I'm rounding the acceleration numbers to 10m·s⁻². It says so in the small print on screen! [edit to add: also, yes, I've also quantised, for want of a better word!]

[@James-wn9qc]

Tom Scott love you!

[@kylecow1930]

isnt it actually 9.81

[@martinsalko1]

Tom Scott I love the noise of the catapult. :D

[@Loadlng]

Notification Squad!

[@j.yossarian6852]

Tom Scott Hey, have you thought about doing on a video on shot towers, the precursor to towers like this one? Theres one encased in a shopping centre in Melbourne if you want to visit Aus!

[@SteelSkin667]

The way it goes up and down perfectly straight is very neat. That's extremely satisfying to watch.

[@slowburntm3584]

I think even a feather would go straight down because of the absence of air...

[@SteelSkin667]

Of course it falls in a straight line, I know how physics works. But the fact that it does so without even slightly rotating, in perfect alignment the tower and perfectly into the receiver at the bottom is still beautiful to watch. Aiming and launching an object straight up like that isn't a trivial task.

[@paveldvorak5512]

I THINK IT DOES THAT BECAUSE OF THE VACUUM AS WELL. As as air resistance comes into play a weight imbalance in the object would cause it to start rotating in some direction.

[@Sailor376also]

Pavel, There is one rotation that is certain, and we have seen it demonstrated many times in many museums, the pendulum that swings freely takes 24 hours to return to its starting point. There are at least two displacements that I know of,, both related to the spin of the planet. However, in 9 seconds,, they will be very small.

[@SteelSkin667]

I think it's small enough that they don't require to compensate for it.

[@jpe1]

For those unsure about how zero-g works while going up and coming down, think back to the childhood activity of swinging on a swing, and jumping off at the top of the swing, and how that “weightless” feeling lasted much longer than if you (for example) just jumped off the top of the sliding board at the same height as (or even higher then) the swing set. That memory is the key to the physical intuition about what is happening in the drop tower.

[@Catladybug]

Perfect

[@Roozyj]

thanks!

[@justinwalker5274]

I love how the technical solution to stopping the capsule isn't to try to time the slingshot to slow it down, it's just 'catch it in a bin of packing peanuts'

[@marcellorenzz9525]

physicist: We could stop it safely with an elaborate system of magnets, air cushions and rotating....... engineer: naah! A few meters of polysterene will do it.

[@Noise-Bomb]

Marcel Lorenzz The simplest solutions are often the best. Cheap, simple and wonderfully pragmatic.

[@RhenusFilms]

Well, magnets might interfere with the equipment inside.

[@md4luckycharms]

To be fair a few engineers probably were saying the same thing until one was like, hey let's just use a bunch of polystyrene beads after sitting on a beanbag

[@stan.rarick8556]

@@RhenusFilms i wonder if the acceleration mechanism is a rail gun...?

[@FreedZ]

@@stan.rarick8556 I bet it accelerats mechanically

[@mamaweasley2812]

that silence from the launch till the 'flop' was satisfying af

[@owenkegg5608]

I'm wondering if the silence is because the near vacuum and then the flop is so deafeningly loud it transmits through what little medium there is and through the structure. Love the noise.

[@Ranstone]

@@owenkegg5608 There's a lot of noise heard. Also, the sound isn't deafening at all. It's just being transferred through the metal, foam, and plastic the camera sits upon instead of the air. "There's no sound in a vacuum" is a myth. It should be "Sound does not travel _though_ a vacuum". The sooner the scientific community stops spreading this misinformation, the better.

[@asyncasync]

@@Ranstone this is not misinformation. This is you being nitpicky. Let me go even farther: "There's no sound in a vacuum" is a myth. It should be "Sound only happens in the brain".

[@Pantology_Enthusiast]

When it landed in the polystyrene, I was expecting a big foof of it. I forgot the reason for the foof is air pressure, something that is not in a vacuum chamber. It's also a bit eerie from the quiet due to no sound propagation through the vacuum.

[@TCraats]

The effects and little screens in the beginning of the video are great Tom! I love that. The tower is very interesting too, maybe I'll go there sometime in the future.

[@TomScottGo]

Sometimes, the camera tracker in After Effects works perfectly! The tricky part was rotoscoping me out so I could walk in front of the third graphic...

[@Daftification]

Do you do all the editing such as those graphics yourself?

[@Tymdek]

I never imagined I'd learn more about the drop tower in a Tom Scott video than in the 3,5 years I've been studying at the university so far.

[@MaiAolei]

This tower was part of a documentary I saw more than 20 years ago (and many times since then, we recorded it). In the segment, they showed how the shape of flames of candles changed in micro-g since warmer air would not travel "up" elongating them. Instead, the flame becomes round and dim.

[@ProgrammierSuechtig]

1:25 Wait... did you just go _through_ an elevator?!

[@mr.boomguy]

that's one hidden room xD

[@ssstjepannn]

Its a decompression chamber xD

[@_TeXoN_]

Yes, thats also the elevator. There is also a door left to the elevator but rarely anybody uses it because it's much smaller and doesn't open automatically.

[@mynamejeff8401]

@@carlhyldborglundstrm9807 ok

[@craigcorson3036]

You've never seen an elevator with two doors? Lots of hospitals have them.

[@ChevronQ]

In Bremen we call it the „Bleistift“, the „pencil“, because it looks like a giant one 😊

[@whoeveriam0iam14222]

They should paint it like one

[@visthevain3706]

Ach auch ein bremer am start👌🏻

[@psvisualdesign]

@@visthevain3706 nicht nur einer xD

[@par5095]

Bremer meeting hier oder was 😂

[@MrDeanWinchester86]

Findorff 🙋🏻‍♂️

[@edwardnigma9756]

Is there a reason they made a tower instead of a really deep hole?

[@TomScottGo]

+Edward Nigma If I remember rightly, it's cheaper, easier to maintain, and makes a good landmark! But there are drop towers in (for example) old mines elsewhere in the world.

[@edwardnigma9756]

Fair enough.

[@Palozon]

Edward Nigma holes are expensive. dirt's slot harder to work with than you would think

[@mariohendriks1]

It's the same reason why most power lines in the world are using tall masts and poles instead of digging underground cables.

[@chraman169]

Edward Nigma They use towers instead of holes because of the water under the surface of the earth

[@HangLooseMongooseYT]

I love how you can tell the only sounds heard by the cameras were from vibrations because of how quick the sound dissipated and didn't echo.

[@jamez6398]

I like how precise everything has to be, otherwise the capsule would go crashing through the ceiling and/or floor and/or walls.

[@ONeill3007]

When you watch some old Tom Scott videos and suddenly see where you work and your professor on screen :o

[@jono2851]

I want to formally thank tom for not cutting the fall into sections with unnecessary slowmo like many youtubers would

[@orti1990]

@Tom Scott, you made a mistake in the calculations at 1:35!! You confused speed with distance. Distance as a function of time should be s=1/2 * g * t^2. The numbers you are saying and showing are incorrect. After one second it has only fallen 5m not 10m.

[@TomScottGo]

True, but explaining that in about five seconds would have lost a lot of people. Sometimes it's better just to do some serious rounding -- or quantising, in this case!

[@yanfe384]

Normally I would agree with that, but in this case... No, the quantisation is way over the top. You could have culculated just the speed instead to make your point and state the correct formular for the falling distance, if you still needed that.

[@Blakearoberts]

Christian Ortbauer hello Albert Einstein

[@ParfaitOperationalGuidebook]

In English?

[@gavinkemp7920]

@TheDiamondRiolu basically what tom scott showed simplified an accelerating object as moving at one speed at on second and an other the next, in this case 10 then 20. in reality the object is accelerating all the way through and of course started slower.

[@joshua7564-s4m]

Tom, I've been watching your videos for some time and thank you for everything you do. They are always very captivating and interesting. Keep up the amazing work!

[@GoldSrc_]

A 360º video inside that would be so neat :D.

[@nessotrin]

Gordon Freeman Well, you should be the one to go in there, you have the hazard suite, I'll wait here ;)

[@jogumemajoli]

@@nessotrin But who ate all the doughnuts ?

[@m4sherman926]

Gordon Freeman Well you are a professional, you should be able to do it.

[@lugin.2828]

@@jogumemajoliHas anyone seen my coffee cup?

[@patrickwienhoft7987]

Can't put into words how much I appreciate you saying "meters per second per second" instead of "meters per second squared" :D

[@enmodo]

My calculations show that if Burj Kalifa, the tallest building in the world at 829 meters, incorporated one of these they could achieve 26 seconds of microgravity. The real problem would be accelerating you up to the 284 mph required to reach the top, and then catch and decelerate you at the bottom when you're going 284 mph again. Doing some more math shows that at five-g deceleration, pretty much the max you can handle, it's going to take 164 meters (538 feet) and 33 seconds to slow you down to stop, and five times that distance (half a mile) at one-g. But hey 26 seconds of microgravity would be a lot of fun and arguably it would be a lot more convenient than going up and down in an airplane. But I guess building an 829 high building and operating a vacuum tube something like twice would be a pretty expensive operation. You'd also want to be damned sure the tube isn't bending or you could slam into the sides one way or the other. Ouch!

[@neilisbored2177]

You'd also want something at the end to break your fall.

[@coolguy284_2]

It would not take 33 seconds to slow down, more like 3 secs to slow down. How did you calculate that?

[@HelloHiHelloHiHello]

You'll end up some Sheikh's boyfriend

[@jischischmaud8379]

What is mph?

[@NedNew]

Once you started using mph and feet you lost all credibility.

[@firstnamelastname4752]

Took me a bit to wrap my brain around the upwards non-gravity, but the video of it working made it click. Awesome work Tom!

[@vvvvwwvvvv8843]

I don’t understand this part. Wouldn’t the payload be experiencing “more” gravity as a result of the launch forces?

[@Wamboo101]

You were in my Hometown and i didnt knew? :(

[@BarryToneLP]

Same here :(

[@aronpuma5962]

Ah yes, I think he explained in Park Bench once that he does not announce where he is going before he films because he does have to be somewhat "on" for fan interaction and normally when he's filming, he gets pleanty tired by a day of filming (filming for this video taking many shots, many locations, and probably much of the day), so he doesn't add on talking to fans for that.

[@goeiecool9999]

Laszlo He was once in Rotterdam (which i live close to). Though he doesnt usually do fan meetups.

[@pulseluft]

Hab mir nur so gedacht: es gibt Leute die sie für meine Heimatstadt interessieren?

[@duckroadsduck3077]

Best channel on KZbin, by far. Frequency, length, content and overall quality of your videos are just so good! Thanks Tom!

[@IstasPumaNevada]

It's one of the few I'm subscribed to that I universally look forward to and unfailingly enjoy every single video uploaded.

[@maxximumb]

If they dug down 50 meters, they could get even more time in micro gravity.

[@IstasPumaNevada]

Of course, but that would be a 50% increase in the length/expense of the tube, plus expensive digging, all for just a ~20% increase in freefall time. Probably not worth it.

[@MDHammond92]

Maxx B sounds good until you compromise the entire structure.

[@chraman169]

Maxx B They use towers instead of holes because of the water under the surface of the earth

[@slowburntm3584]

@Chraman How would water effect anything? Our Nuke silos are underground...

[@chraman169]

+Slowburn There is a big river in Bremen. The Silos are not 140m underwater.

[@msgordito99]

(1:35) If we say that an object is in free falling, and ignore air resistance, with a constant acceleration due to gravity (g, in m/s^2), then we can know the position (x, in meters) at any instance (t, in seconds) relative to the starting point. That is: x(t)=(1/2)gt^2.

[@jamescounter2337]

Escoba Sin Gracia I'm pleased it isn't just me who spotted that

[@philipgeorge1253]

scott you said the capsule move 10m in the fist second but it is actually 5m (if g=10m·s⁻²).the equation for distance is ut + at²/2 where u is the intitial velocity, t is time and a is the acceleration

[@rynabuns]

Philip George v is always final velocity. u is always initial velocity. We use u because it comes before v. There's a reason the 5 equations are called "suvat equations".

[@Chew1964]

And after 3 second it would have fallen 45 meters. After 4 seconds it would have fallen 80 meters. The only one he got right was the 2 second fall but that was just a coincidence.

[@morethejamesx39]

He must have been referring to velocity?

[@cubetube7454]

3:(67*{5~•}

[@Jona69]

"Roughly"

[@MsLightbar]

I did not expect the upward motion to be part of it. This is an awesome video, thanks.

[@turun_ambartanen]

that foortage of the capsule is awesome!

[@rubiumproductions]

The shot of it going up and then down again is mesmerising...almost hypnotic...Nice sound accompanying it too!

[@bulman07]

Took me another couple of minutes after the video (and watching the launch a couple of times) to understand how it's zero G all the way up and down. Scary how quickly academic education slips away.

[@bulman07]

Xiefux After it's launched, the only force acting on it is the constant of gravity. So from its perspective it's in freefall the whole time.

[@shbptl111]

Andrew Bulman I still don't understand. Could you please explain it in detail? Thank you.

[@joshtiel2980]

TheHolyDonut001 this is because the up minus the down cancels each other out? Seems odd to be travelling at speed yet weightless but I guess that is how the ISS works. Thanks for the explanation!

[@al35mm]

@@joshtiel2980 No there isn't a cancellation. There is only a brief period of acceleration as it is slingshotted. During that acceleration, you would feel a lot of gravity, but once the acceleration stops and the capsule continues on its upward trajectory, you would feel the effects of 0G. It doesn't matter what direction it is moving in as it's only relative to the acceleration of gravity. So if you are no longer accelerating, you have 0G. For that reason, if you were inside the capsule and couldn't see out, you would not be able to tell when the capsule stops going up and starts coming down again. Put it another way, gravity is a force of acceleration. While you sit in your chair with your feet on the floor, you feel the force of gravity accelerating you downward toward the chair and the floor because your body and the chair want to fall through the Earth but can't. Remove acceleration and you remove gravity.

[@jofa4050]

@@shbptl111 It took me also a bit^^ But its not getting accelerated all the way up, only in the beginning. So while it is going upwards with its starting speed, gravity is the only force on it. The moment it leaves the 50g acceleration it already starts falling. the falling is reducing the starting speed, turning it into zero and then into negative speed. genius engineering!

[@HGGdragon]

Thanks for this video! I've lived pretty near to the fall tower and walked past it every morning. Now I finally know how it exactly works :)

[@mrjoa96]

The shot of the capsule being launched is unreal

[@duroncrush]

This is a very cool research tool. Which is subject of the video, not the math describing a falling object. In just over 4 minutes Tom showed us the free fall tower and a basic overview of its operation. Good job

[@SapphireCrook]

I love how the only noise the landing makes is the pellets crashing into the objects. Almost like rain!

[@brucealmighty3824]

The pellets are in the vacuum as well so there shouldn't be any sound at all. Maybe it is coming through the structure?

[@MarkW_]

Hands up from the people that participated in the REXUS programme and have been at the drop tower for bench testing :) Very nice facility and very friendly people there.

[@pocketdialmusic]

Great editing in this. Especially the beginning bit

[@ailaya5127]

I lived in Bremen and everyone knows that tower. I knew that they make 0G experiments in capsules, but I though they would just let them drop and that those capsules have the size of a football. I am amazed. Thank you!

[@BOLL7708]

My brain told me "lul no way that will fly straight..." then I realized that why does things not fly straight most of the time? Air resistance, and the air has been removed, so duh! Well, super interesting and slightly insane :) Hardest part to understand for me was the constant force application but it makes sense, as long as things to be zero-g-ed are released post-launch it should be fine or they'd be firmly situated at the bottom of the canister. Or something like that :P

[@agerven]

@Andreas Aronsson: True for the center of mass. There is a little extra complication though. When there would be a slight residu of rotational energy the cilinder could still rotate around its X- and / or Y- axes (naming up/down the Z-axis) in which case it could crash into the sides of the tower.

[@BuGGyBoBerl]

@@agerven + you also need to be very precise where you shoot it. little bit to the left can also cause damage

[@kaltenstein7718]

there actually is a bit of margin, as by going up they mive away from the earth, thereby being subjected to a difference in angular velocity, resulting in some shifting due to earths rotation

[@lexguttman]

That was my fav video you've done so far. Great info, fantastic camera/editing job.

[@artgreen6915]

German engineering! The main event operated so smoothly it was almost an anticlimax. What Tom didn't emphasise is yes your experiment gets 10secs of zero G, but its preparation will need to be resilient to the launch G, and results withstand the braking G.

[@user-yv2sc5qv7x]

Best use of an oversized beanbag I've ever seen! I didn't expect the sound recorded. Amazing

[@ch6uncey240]

It’s so satisfying to see the Camara fly so smoothly through the tower

[@playfast321]

i was weirded out with not hearing any air rush on camera after that launch, until i realised there was no air to create that sound! very cool

[@ashtonlastname489]

I love how you add the uncut footage as well

[@timothyhayes9724]

Dude, watching that shot made me feel like I was flying up, in zero G, and then falling back down. That's so cool!!!

[@BoomBrush]

i understand how falling creates zero g, but how does slingshotting to the top create zero g?

[@lokegustafsson247]

BoomBrush The acceleration stops less than a second after being slingshotted.

[@jonnenne]

You get 0 G at the absolute peak just as the "sled" is stationary. So they get 2 significant measure points instead of 1.

[@FlyingJetpack1]

Speed is a relative thing, it doesn't matter if the object is going up or down, as long as the only force it is experiencing is the constant acceleration of gravity, it will imitate a zero G environment even thought the object is well withing the gravity pull. You can "feel" that you are starting to switch from rise to drop just because of the air around you and other que. But when you eliminate everything but the gravity, you achieve an almost perfect simulation of zero G

[@somitomi]

The idea here is that since the capsule (and everything within) accelerates at the same rate (somewhere around 9.79 m/s^2), the things inside appear weightless. It's worth noting, that this isn't just similar to the weightlessness experienced by astronauts, this is *the exact thing* that makes astronauts weightless in orbit. While gravity is weaker at that altitude, it's not quite zero. EDIT: Yes, I messed up some calculations. I apologize.

[@piraterubberduck6056]

acceleration is change in velocity. slowing down is change in velocity, the same as speeding up. once out of the cannon it is only accelerating due to gravity. this means that anything in it is in free fall both going up and down.

[@joel30466]

I think it's really interesting how smooth the capsule goes from going up to falling, it almost looks like the direction didn't change at all.

[@alba-atheist]

Actually it a modern unseen university and they are all wizards. (wonder which one was Rincewind?)

[@666Tomato666]

Rincewind was, as always, on a "visitation" abroad

[@trinitygod863]

At high speed

[@alba-atheist]

W0Ndr3y I was really quite disappointed in the number of "intellectuals" squabbling about minor points, each trying to out pedant the other. Hence an attempt to lighten the mood. Couldn't help notice the similarity of the high tower at a university though. Terry will be sadly missed.

[@jonjon7311]

I was glued to the screen and listening intently and I understood ABSOLUTELY NONE OF IT.... but yes it was incredible... 👏👏👏.

[@Vogeluff]

and here i am, living in bremen not knowing that. thanks for the video!

[@ulin4226]

Thanks for that clip! That brings back memories - I was stationed in Bremen during my service time and I saw this tower being built.

[@Yookiwooki]

Wouldn't the capsule go 5 meters in 1 second with an acceleration of 10 m/s^2?

[@mistaecco]

Tom, you've done amazing videos before but I think this might be my new favorite. Amazing work!

[@MCKoolperson9]

Wow, that's incredible, and oddly satisfying.

[@BlameItOnGreg]

Was not expecting that awesome footage that went along for the ride. It looks super cool!

[@niklaspilot]

Ok, now I know, the best thing about Bremen isn't the Autobahn to Hamburg but in fact the Drop Tower! :D

[@YunoManic]

There is nothing good about the Autobahn to Hamburg; unless you like being stuck in traffic jams, that is :P

[@niklaspilot]

True that is. But the city you end up in after you got through the traffic jams is much, much prettier! ;)

[@YunoManic]

Eh, neither of them are all that pretty overall. They both have their gems, but I wouldn't call Hamburg much prettier. If you want to see pretty, try Gosslar. That is one pretty city if you ask me. (Also has way less traffic~)

[@niklaspilot]

I was born and raised and have been living here in Hamburg for over 19 years now. There is no city that is more beautiful than Hamburg (apart from Stockholm maybe; in a very close second place ;))

[@cduemo]

It's been 40 years since I took algebra, but an acceleration of 9.8m/s/s gives you a VELOCITY of 9.8m/s AFTER 1 second, which means only moving 4.9m in that time.

[@benpowersification]

Sooooooooooooooooo satisfying! It even goes "ploomf" when it lands? Surely this is art not physics?!

[@towerclimber7277]

That's just cool as hell, love the variety you provide... Thanks alot for the videos!

[@JoeBleasdaleReal]

3:38 is that not the old Robot Wars title sequence?

[@Ranglebox]

Close enough.

[@Leffrey]

I love how quiet it is. Obviously in a vacuum you wouldn't get much sound, so this is all traveling through other materials and what little air is left, but could you imagine what that's sound like at full volume?

[@Skip6235]

Where did the sound come from when the capsule hit the bottom if the chamber is a vacuum?

[@TomScottGo]

+Skip6235 It's not a vacuum if it's filled with stuff! Sound conducts through solids as well as air :)

[@dj94545gaming]

Skip6235 Skip6235 to add to what tom said, the camera is attached to the wall and the things that make noise e.g. the sliding of polystyrene pellets makes a noise and the bass travel best through the wall this the noise we do hear is low.

[@hellterminator]

Sound travels through solids too.

[@syntaxis5584]

There's no sound in a vacuum because there's no air molecules to vibrate, however, the capsule hit the bottom of the chamber vibrating the steel which travels outside of the vacuum chamber to be heard by the camera.

[@Skip6235]

Oh, I see, so the camera was picking up the sound passing through the actual barrel the capsule fell in to. Interesting!

[@Grablgmork]

Just to clarify (and because I also had that wrong for quite a while): The zero-G part of a parabolic flight is not because the pilot accelerates the plane downwards, but kind of in the same way as in the drop tower here: The plane stops accelerating in an upwards angle and just follows a curved path like it would have been thrown.

[@WillHirschUK]

Things that have been thrown accelerate downwards...

[@goeiecool9999]

Will Hirsch things inside the thing that you throw accelerate downwards at the same speed though so relatively they experience zero G

[@WillHirschUK]

Exactly. In order for objects in freefall to accelerate at the same rate as the plane, the pilot has to accelerate the plane downwards.

[@Ravaxr]

Really interesting thing I noticed about the experiment as it was falling: It has a few polystyrene pellets that also took a ride, and they fall at the same rate as the capsule. It really is a vacuum in there!

[@RinoaL]

that is the most amazing footage i've seen in a long while :O

[@kasane1337]

I don't know why, but as a German-speaker, I always start smiling when I hear someone with a German accent. If it's any other accent I pretty much ignore it, but when I hear the German pronounciation it always makes me smile.

[@ltybc425]

Thanks for attaching camera to it! This is just what I wanted to see

[@ZmakiZ]

How did the landing make a sound in the vacuum? Was that a little bit of editing trickery?

[@TomScottGo]

Sound conducts through objects! Sure, in space, no-one can hear you scream, but hit a braking system at 50g and someone'll definitely hear you clunk.

[@BigDBrian]

the microphone can still pick up vibrations from what it's attached to!

[@giuliorasi]

the sound is transmitted through the capsule itself to the camera microphone.

[@ZmakiZ]

Ah, of course, Should have realized. I blame Mondays.

[@Kassidar]

In space no one can hear you scream, except yourself... and it would sound weird.

[@nicksmarto]

@Tom, does the experiment have to include any corrections for the coriolis effect from Earth's rotation (perhaps a slight correction in the launch vector?) Or do the orders of magnitude at play here make such effects negligible? Enlightening video as always, good sir!

[@IstasPumaNevada]

ZARM latitude: 53.1103°. Altitude of Bremen: ~10m. Earth radius at Bremen, due to imperfect sphere: 6,364,509m. Drop distance is 110m (says Wikipedia), so radius of top of the drop is 6,364,619m. COS(53.1103) is ~0.6. V at base of tower: 277.8320 m/s. V at top of tower: 277.8369m/s. Difference: 4.9mm (~0.2 inch) per second. So less than 5cm/2in displacement for the 10-second test. Small enough to easily account for.

[@kaltenstein7718]

From what they told our class when we visited, They shoot straight up and just accept it coming down a bit off Center

[@StonyRC]

Tom, that is freaking AWESOME!

[@WeUsedToWonder]

The end gave me chills.

[@TheTopLogician]

I love the camera tracking and the rotoscoping with the video inserts at the beginning. That must have taken forever!

[@tomporter8849]

That catapult is an amazing piece of engineering. Imagine how hard it must be to project it so precisely that it doesn't hit the walls or tumble in flight.

[@gracelandtoo6240]

It flys straight up and down bc of the vacuum

[@_S0Y]

this is by far the coolest things ive never seen before and my yt history runs deep

[@fuzzzbuzzz4208]

Me: you can only really get zero g on earth through those plane things Tom: *there is another*

[@MrNukedawhales]

technically "those plane things" arent on earth when they reach zero g, just saying...

[@anonnymousperson]

That's just amazing, so cool that that exists. Love seeing the video of it launch. Thanks Tom!

[@foxtrot151000]

I had a thought, how much would the capsule drift with the rotation of the earth underneath it. or is the rotation added to the force on the capsule, thus it would land in exactly the same place it started from? also, this is cool.

[@goeiecool9999]

foxtrot151000 I thought about this as well but I assume its either accounted for or insignificant at those heights.

[@shTree]

foxtrot151000 Yeah, Is guess that the Coriolis effect is just so minor it isn't going to cause any problems.

[@arcer63]

foxtrot151000 the rotation of the earth is there at the time it is launched. Therefore the rotation of the earth doesn't really occur "in the system" of the experiment but "on the system" of the experiment. The earth rotates at 600 mph in germany, do you think about that every time that you throw a ball? If there was an angular acceleration, this would be a valid concern, but it is just an angular velocity. Basically the same reason it is shot up with Velocity and is still considered weightless for the entire duration of the experiment.

[@foxtrot151000]

arcer63 yes I understand all of the inertia stuff. what confuses me is when the object reaches its max height it would need to move a little bit faster than the Earth's rotation to stay exactly underneath it. like the edge of a wheel moving faster than its spokes. the difference in launching position and landing position would be tiny but it should still be measurable. I think

[@shTree]

foxtrot151000 Yup, you are correct. Someone did the calculation in the comments I think, you might be able to find it.

[@kjamison5951]

I got what you meant when you said roughly 10m/s/s That is a truly fascinating structure! Thanks for the video!

[@PlasmaHH]

Oh the memories from seeing that place again....

[@oliveratling3463]

Dennis Lubert do

[@markiangooley]

There are of course a few old surviving drop towers built for making near-spherical lead shot. Melt the lead and drop small measured amounts, and if all goes well you get decent-quality freshly-solidified shot hitting the (padded?) floor. Much cruder, just molten lead falling through air.

[@snaileri]

I don't get it. How can the capsule be weightless during the whole time if the launch causes such high acceleration?

[@quietsamurai1998]

snaileri As soon as the launch is over, it's weightless.

[@nikofloros]

Because free fall up is the same as free fall down.

[@stevenyau2443]

the launch part is only a few tents of a second. 0.2 seconds as stated by some. so the rest of the way upmit will experience freefall.

[@2000leonel]

It "feels weightless but tecnically it's still being affected by gravity. Basically after you launch the object it is only being affected by gravity, with an acceleration of about 10 m/s^2 . The only difference is that it isn't being applied a Normal reaction force. Simply put: The normal reaction force is a force that is exerted in you by the things you are standing on. For example if you sit on a chair, gravity is pulling you down and the reaction force is pushing you away from the chair. There is no point in this experiement where gravity isn't being applied

[@MichaelDreksler]

The problem is the term "zero g", what we actually mean is free-fall. Even things in space aren't in 0g

[@newguy3588]

That is one of the most fantastic thing I've ever seen.

[@cursedcliff7562]

Germans 1943: We make complicated tanks with overlapping wheels Germans 2019: Haha polystyrene go whoosh

[@QuilloManar]

The thing that intrigues me most is that the camera that was on the capsule was recording sound the whole time; but you didn't hear any wind noises. I mean obviously, there is no wind because there is no air.

[@Commandelicious]

Obligatory 'we from Oldenburg hate Bremen'-comment here. I didn't know Bremen had such a thing and I am about 40 km from that thing oO

[@YunoManic]

You can rest assured, that Bremen does not concern itself with the petty hatred of such insignificant villages. Except for maybe the football fans, seeing as Werder might soon play in the same league as oldenburg if they keep on sucking.

[@Commandelicious]

Har har har The football fans are one of the reasons we hate Bremen. Well, at least for me it is. You can't go to Bremen without seeing someone with any kind of fan-item :E

[@S404_44]

Commandelicious Bremen ist voll nice, alter :P

[@Croxmata]

I am about two hundred metres away :)

[@FridgeEating]

I've paid both Bremen and Oldenburg University a short visit and both seemed quite nice. It's probably the rural atmosphere. Although if you plan to do anything serious you might want to leave your pretty villages and head to the city. I'll see you in Hamburg at DESY.

[@MetalSombie]

Wow, amazing Video! I loved the Sense of momentum this Video had!

[@aashaytambi3268]

your calacutions are off. the forulat is 1/2gt^2

[@aashaytambi3268]

Thanks!

[@murk1e]

That's far too strong. Mistakes happen. The mark of someone with a decent physics education is not never erring, it is correcting the error where needed.

[@murk1e]

Nillie I didn't take a variety of subjects, but I picked up lots about a lot of them. Grown ups can (should) continue to educate themselves. It may be that Tom didn't know better, it may be an honest error. Until demonstrated otherwise it's more charitable to assume the latter.

[@aashaytambi3268]

Yes but he needs to learn it, beter no info then wrong info.

[@tomyao7884]

I was scrolling the comments to see if anyone else noticed, because that was exactly what I was thinking the entire time! It kind of goes against my intuition to say that it traveled 10 metres if after 1 second, the end speed is only 10m/s. You don't need to have a physics education (i don't, at least not beyond middle school) you just need to think about it logically, or have a good enough intuition.

[@martinsalko1]

i love it this is so far one of the best videos of 2017!!

[@volbla]

Doesn't the acceleration harm the equipment?

[@stefanozurich]

Volbla I would assume that it is designed to withstand the acceleration.

[@Aldurnamiyanrandvora]

Also if they do plan to put any of this stuff into space (not saying everything will be put up, but if they do) they need to make it take the acceleration of a rocket launch

[@stefanozurich]

The acceleration of a rocket is much much less than 50G

[@floridmonkey2723]

Usually its 5G, tops.

[@coolguy284_2]

@@stefanozurich unless its that sprint 100G rocket

[@zapfanzapfan]

That footage going up and down was proper SciFi!

[@mackpackable]

Hey, I work in the building right next to that :D

[@ing3888]

Really nice editing, props to whomever did it

[@PhazonSouffle]

I want a ride on that. Someone rent me a spacesuit.

[@EdwardDowner]

Not when you are launched at 30g you don't.

[@calaphos]

you could probably survive in the right position

[@TheInsaiyan]

Edward Downer yeah humans can sustain a high amount of G forces for a very short period of time. And the record is 25g for 1.1 seconds. But the 30g's in this thing a certainly too much for an average human. Even the guy with the record was probably a very fit individual. Even if you survive. You will take some damage. Either that or your brain is mush. xD

[@slowburntm3584]

I think the video said 50g at one point, so probably not.

[@joosekraft3405]

@@slowburntm3584 yes the deceleration at the end is 50g