Tutorial: Rocket Science! (plus special announcement)

The basic physics behind how rockets work! (plus a special announcement)
Perimeter Institute: www.pitp.ca
VomitPhysics video: • VomitPhysics! Physics ...
"Milkman" by freddiew: • Milk Man: World's Wors...
Bottle rocket video: • 2 Liter Soda Pop Bottl...
For more detail on rocket physics: www.real-world-physics-problem...
Floating on mercury image: wordpress.mrreid.org/2009/09/1...
Molten lead image: www.boattripsiona.com/news.htm
minutephysics is now on Google+ - bit.ly/qzEwc6
And facebook - / minutephysics
And twitter - @minutephysics
Minute Physics provides an energetic and entertaining view of old and new problems in physics -- all in a minute! Created by Henry Reich

[@MaeveFirstborn]

"It's not rocket sci... wait it is." KSP scientist 2012

[@CreeperUniverseTV]

Yup.

[@magicmonkeyking4137]

2019 and it's still the same! XD

[@CharlieSnowball25]

You lost me at "We're going to start with a rocket"

[@telesman8823]

Charlie Snowball I am a 12 year old who understand all of this

[@jellevandenbrink1524]

Thunder Bolt Im 7 years old and I understand ALL of thia

[@melancholyentertainment]

+Jelle van den Brink I am an actual fetus in a womb and I understood all of this...

[@jellevandenbrink1524]

Mysterious Enigma Im actually a sperm cell and i understand ALL of this

[@ultravioletgamer90]

+Jelle van den Brink My grandfather is actually still a sperm cell and I understood all of this...

[@WarrenGarabrandt]

Instructions were unclear. My refrigerator is now broken.

[@pedropuglia2650]

Instructions unclear. Stuck penis in the fan.

[@workhardism]

Instructions unclear. Already fried 20 neighborhood cats. Still no free energy. Will keep trying.

[@darmblesvlogs]

Instructions unclear: i successfully created a rocket but i got a but mixed up with quantum phisics and now its phasing in and out of the earth at near the speed of light

[@spookyboi9693]

Instructions unclear I made a Nuclear war head and have now started ww3

[@CompCode-Central]

@@spookyboi9693 😂😂😂good one bro

[@user-zw3iu5hx1d]

I would need to exhaust 3,1 liters of water per second to levitate

[@ricardomianelli]

That means i can teach "Fly" to a Squirtle?

[@sh4dy832]

Ricardo M. Ianelli Yes, but you have to consider that the water it shoots out is originally additional mass of ... nevermind, it's pokemon. So yes, if you can teach it to shoot out the water at a sufficient velocity.

[@javedansari-nb2pk]

That creates a question. Where does squirtle get water to throw. If it has infinite water then it has infinite mass meaning greater than sun and even black holes and everything would revolve and eventually collapse in squirtle’s mouth. Does that mean you destroyed the world you imagined by adding a squirtle?

[@Cl0ud897]

@@javedansari-nb2pk It can collect the water from the atmoshpere tho

[@javedansari-nb2pk]

@@Cl0ud897 the rate at which squirtle throws water, I don't think even diffusion would allow that rate

[@GrizzLBD]

If MinutePhysics wanted to make a series of 3 hour long educational videos, I'd totally watch them.

[@CallMeFlooty]

That would be a lot of minutes

[@fadydavis7457]

Hourphysics 😅

[@HT-rq5pi]

With formulas like the ones in this video, i can only truly understand it when im sitting at a desk with a pencil and a piece of paper and attempt to derive it by myself. Its just too difficult to grasp the concepts when someone is verbally explaining it to you.

[@Coopkaboom]

That’s exactly what I’m doing right now, writing it all down, watching it again, then I explain it to myself and work on the comprehension peice of it

[@luisgomez8102]

Anyone else looking at the comment section for someone who did the milk vomit equation?

[@erdbeerenundso7753]

0.2 m or 20cm radius of your throat seems a little overkill to me...

[@earlybird884]

Me

[@sawc.ma.bals.]

Me

[@tigerli8453]

i was looking

[@shayaanlindow8180]

zuyash what he did lol

[@RaimarLunardi]

Instructions unclear, end up in the moon...

[@BarcalonaBoy6]

Not to be that guy.... But if you ended up on the moon I think the intructions were very clear. :)

[@gottabweird]

- Josode - But he said IN the moon.

[@tsjerkwicherink9245]

I think I figured out what went wrong,you multiplied times 1000 instead of deviding. So basically you went way too fast

[@IssaMe]

OR he plays too much Kerbal Space Program and got advice from Kerbals...

[@mirjanadekanovic14]

Raimar Lunardi instructions unckear. Dick stuck in toaster

[@galaxyn0va392]

This cant be this hard, i mean, its not rocket science

[@vaughndoyle5489]

krobygaming alexander i know its been 2 months. but thank you.... someone had to say it.

[@SillyGoose2024]

Gay

[@pietrocelano23]

+uannoyme74 wow, such creative

[@whig3982]

fuqing idiots

[@slimemade4war921]

Its a joke

[@jakez082]

Clearly Kerbal Space Program has taught me nothing.

[@animationspace8550]

This is real late, but it taught you everything but without the maths

[@dibbidydoo4318]

If this is simplified version of basic rocket science then I hate to see the original.

[@muizzy]

The only real difference is that real rocket science uses multiple sources of gravity and/or differential equations, which are a little tough

[@s694019001]

wow... you have come a long way in how effectively you convey your information in just one year. Yes this is nice and all, but if you watch this and then something like his introduction of the universe it's clear he's gotten better at speaking and editing and... well everything. good work minutephysics! loyal subscriber

[@mastoner20]

Congrats with the PI bit! I'd just like to point out quick, that as a student studying Theoretical Physics as well as Applied Mathematics, I'd like to thank you dearly for these videos! They do help drastically in explaining some simple concepts very well, and clearly define the very basics of some very difficult concepts! Keep up the good work, good sir!

[@talrefae97]

As a physics student, I wish you'd make more videos like these. THIS is what I go through while studying physics and it's a good representative of what's to come in university. I hope people understand that whenever we physics people try to explain physical phenomena in non-mathy terms, we do it by translation - and because it's a translation, we can never give you the entire picture. Nature is intrinsically mathematical so there's no use in learning physics without doing math.

[@justaregulartoaster]

Instructions unclear. Currently stuck in the ceiling fan. Update: i managed to turn off the fan. Update2: obtained basic knowledge about vomiting

[@Reversefilms]

this is my favorite minute physics video ever

[@TheAlineFlorence]

You explain so well , it's just amazing. I wish my physics teacher'd be able to explain as well as you do !

[@Alexander-wq3mh]

Why am i not surprised nobody posted howmuch they need to vomit to levitate :P

[@Hornet0biker]

No, we are way too stoned to attempt such a feat.

[@jacobfranco3378]

correction my friend just tried to levitate by vomiting. Sorry but I was too disgusted to measure the Rate of the flow of the vomit but his mouth should be the size of 6 cm2

[@bubugosk]

Minutechemistry needed! love the channel!

[@samuelparcon8121]

I find it awesome that I fully understood the video and the derivations of the equations :D

[@with-katnik6950]

5 gallons = 18.92 liters

[@djmintyfreshful]

in one second? damn

[@chetanphoenix]

The formula is actually volume per second to be expelled to hover. Little unit calculations Sqrt(A.M.g/density) which is sqrt (m^2 . kg . m/s^2 ÷ (kg/m^3)). => m^3/s

[@djmintyfreshful]

good work

[@adeel256]

I appreciate the pause between segments of equation solving process.

[@CheckeeAintAmused]

DO MORE TUTORIALS, PLEASE!!!! THESE ARE FANTASTIC!!!!!

[@isodope5800]

Your final formula gives the volume of fuel needed to hover for one second.

[@ofrikirshen3071]

It's an equation to calculate the rate of water

[@nihaljalal5693]

please make more new videos explaining physical theories.

[@TheAlexdodd]

It's a type of refraction, the sloping of the bottle or rocket towards the opening increases the velocity very quickly, and when it hits the open air it spreads out in a cone like pattern. If the diameter of the bottle and the opening are the same, then the water will come out in a cylindrical patter.

[@superpiratesVsninjas]

You my friend, are a genius!

[@matiasespinoza5628]

It is 1:03 AM and I'm learning rocket science... nice

[@vos2465]

I appreciate that you included the math, I going to use a lot of it! I'm starting a career in exactly this, rocket science, so many thanks!

[@farukbalc598]

Vos Topps You are starting a career in rocket science and you learn the basics from a youtube video. I wish you success.

[@769270865]

Vos Topps Do you mean KSP!?

[@kemolegend907]

Faruk Balcı he's probably just starting college

[@liveoutloud88]

Congrats about the Perimeter Institute. It looks like a cool building. I'm doing my Master's at the school across the street.

[@lalacoopcoop]

wow! your stuff is so great! I don't like math (at all) but your videos make it really interesting!

[@leviconstantin3274]

play ksp now on a computer you will learn about rockets

[@StarLink149]

+Levi Constantin I used to played KSP a lot, but I never had enough patience to do all the math. I never got beyond the Mun and Minmus either...

[@leviconstantin3274]

+StarLink149 I went further but with infinite fuel cheats

[@StarLink149]

Levi Constantin Yeah, well, I did the same. But that doesn't count.

[@MythCraft00]

+StarLink149 I've sent Jeb in Duna orbit, an then I took him back home

[@sagiksp4979]

+MythCraft00 Cheats?

[@kdmq]

I just compared this video to an instructional to approaching women. I gotta say this shit is actually easier to understand!

[@omarrahman4895]

+kdmq For someone who understands both, I feel sorry for you

[@danielwheeler3897]

+Omar Rahman stfu....

[@goalieonfireiamone1761]

TRUE

[@MusicalInquisit]

This is why there a lot more nerds than pretty much anyone else who understands rocket science...

[@markurrito]

I know I'm late to the party, but I couldn't agree more with you.

[@geni1intake]

@kevin weiss, the gravitational pull stays the same no matter how fast you go, the air resistance would increase along with velocity but he didint take that into acount

[@nolanjshettle]

Loudness is usually correlated with sound pressure, and these pressure waves do exist in the rocket's exhaust, making the rocket just as loud in space, as it is in the atmosphere, as long as you're close enough to be within the exhaust with a high enough pressure.

[@Vanddark]

Damn, I were eating when I saw the vomit scene. :P

[@shamalk]

me too.

[@crap9105]

Ah, that's hot

[@CompCode-Central]

😂🤦‍♂️

[@PeterPete]

Good video, nice to see someone recognizes that a rocket thrust generator 'exhaust' is part of the mass of the rocket (system). However what the video does not explain is how it actually propels itself upwards. In simpler terms, what are the forces involved and where are these forces applied to create the motion of the system. All the maths does is to enable someone to calculate how much thrust force would need to be generated to move a particular sized mass. It seems where, and how these forces are applied, is anyone's guess. From the video, the description should not read, "The basic physics behind how rockets work!" but "The basic maths behind how rockets work!"

[@windrainziyi]

as long as the opening for thrust to come out is smaller than that of the fuel container/flow line, then it is getting "squeezed" out, or put under pressure, so the object trying to elevate, (Milkman) can go higher than the tank/stomach height.

[@sandylandin6934]

What a good way to explain that

[@ROCKET-qs9ch]

My HEAD went BOOM!

[@muddymutt5815]

He sounds so SAD in this video. Or unmotivated...

[@LightningFlare95]

I don't even do physics and I still love and understand all of his videos!

[@James01100011]

Good video, makes math look fun.

[@The112Windows]

I was hoping for a bit of calculus in this video. (Because we are talking about rates)

[@The112Windows]

***** Nice.

[@danielalexander9982]

***** Yeah its missing dm/dt as well as dg/dh, however an integral is not required, you arent really simplifying the math for ejected mass, due to the fact that simply knowing the R constant will simplify the entire equation. You cant really use average mass seeing as different masses at different heights makes the largest difference to calculation. Its really a large problem of related rates(dm/dt and dg/dh.... oh and d(theta)/dt(for trajectory))

[@sirawesomehat8814]

I like calculus.

[@psharmacgk]

Geekminer Calc doesn't seem to appeal to most people :( you can find some interesting things after the credits of his proof of conservation of energy vid however.

[@davidflores909]

I don't know calculus :'( Someone teach me, or tell me where it is kindly explained for newbs. I like programming but there is some problems I just can't solve to turn them into algorithms because my math doesn't allow me, it feels like a freaking wall. I only know derivatives but I just make the process mechanically, so I don't know how exactly the answer relate to the problem.

[@shayaanlindow8180]

In 1986 (?) a rocket blew up during launch. Seven died, and millions were saddened. Do you know why? It was cause of a rubber o-ring being too cold. Seven people died off of a ring. A fucking ring was too cold. Rocket science is hard because the margin of error is so small, one tiny mistake can cause stuff like that to happen. That’s why rocket engineers are so smart, they are trained to look for every little detail.;

[@williamchamberlain2263]

True, but the o-rings were not designed properly, the cold just made catastrophic failure more likely - Rogers Commission Report

[@ObalucawTheMan]

Most educational channel ever! :D

[@nathanspringer9902]

I wouldn't think so. On one channel I watched a demonstration on how to burp, fart, and pee at the same time

[@Drion_MCGD]

@@nathanspringer9902 wow just wow

[@Drion_MCGD]

@@nathanspringer9902 now tell me how to pee,poop and vomit

[@TheCommandoDuck]

This is one of the few videos that I actually understand.

[@Dueck25]

I really wish I understood any of this

[@MrDrSlime]

You lost me at Hello

[@CompCode-Central]

🤣🤣🤣

[@nathanspringer9902]

@@CompCode-Central I didn't think it was that funny

[@DayhawkinDark]

@PROgrammer All liquids are incompressible but can be put under pressure. Liquids can only be displaced.

[@hellogovna]

I’m *exhausted* after watching this!!

[@samuelprice538]

if you ejected the fluid at a higher speed you would need less fluid. E.g. if you can vomit at near the speed of light you wont need much milk to hover.

[@CatFace8885]

Problem is, the impact of Milk traveling near the speed of light directly into earth would be so strong, it would create a nuclear explosion. (Not exaggerating, it literally would.)

[@samuelprice538]

Well I was exaggerating for effect but the principle is the same. On a related note the "What if" book by XKCD guy gives a great description of what happens if you throw a baseball at 99% the speed of light (on earth).

[@michalsimanek6988]

Nah. So complicated. Just play Kerbal space program and hopefuly you get orbit :D

[@sagiksp4979]

Jebidiah Kerman lol

[@ayjayahmed]

+Jebidiah Kerman Pretty sure I killed you with my first attempt to get to the moon

[@sagiksp4979]

My last name is kerman Come here brotha

[@leviconstantin3274]

its jebadiah Kerman and I'm bob Kerman

[@sagiksp4979]

Levi Constantin No you are Levi Constantin

[@Glaswalker1001]

Thank you for showing me the spellchecker side. It will help me save myselfe from grammar trolls a little better. So we both learned something from this little discussion.^^

[@nintencivo1500]

Becuase in math, "x", usually represents an known variable, so in order to not get confused, the "times" operation is represented by a dot or an asterisk (*).

[@karl95hansson]

okay... M=57 kg A= 0.04^(2)*PI=0.005026... m^(2) => squareroot((0.006026...*57*9.8)/1000)=0.0529889597...m^(3) 0.0529889597...m^(3)*1000=52.9889...~53 L soooo... 53 liters of milk (or whatever it is I'm vomiting)

[@JaX0rton]

That'd be 53L of water. Milk is around 1.032kg/L (based on a quick Google search). Answers would be slightly different though I guess we catch your drift.. thanks for working out the math :)

[@karl95hansson]

JAnderton true... oh and by the way... if I would hover, I would be forced to vomit the same amount of mass/second as my weight is... meaning that I *actually* have to vomit 57/1.032~55.2 liters of milk... that means that the actual calculation I did and the calculation he showed in the video was *excesive* and it also means that the area of my mouth wasn't exact, but good enough...

[@Keddemand]

karl95hansson ....and it would take less and less milk to keep you hovering, since u loose the weight of the fluid, while puking.. thats what u ment, right?

[@karl95hansson]

Keddemand actually I did not think about that... but that is 100 % true

[@Keddemand]

karl95hansson Sir, thank you for making me feel awesome about myself :)

[@karl95hansson]

I managed to get through everything, except I understood 57 %, I'll watch it again

[@pancakeho0e]

why 57% not 56% .... am i right ? :P

[@karl95hansson]

khalil mteirek nope, exactly 57% :D

[@The.RandomTube]

Incredible

[@everyanyelse]

I'm near your age, and although I had to slow it down, I understood everything. It's like reading literacy, soon you'll pick up what the terminology is if you deliberately practice and question your thinking. If you find it easy to think in pictures you could illustrate rocket for example with the laws, math and reflect that. I hope it flows like a movie eventually and over time be intuitive to understand.

[@captinobvious4705]

its rocket sciencs waht did you expected but a headeach

[@michaelmcgoldrick6282]

I need to stock up on milk.

[@nathanspringer9902]

Did you ever stock up on that milk?

[@jar0bi]

please do more tutorials henry!

[@ImperatorSupreme2]

I know a bit more about rocket science: the expulsion rate of water and its velocity make up specific impulse, take this, combine it with the first mass divided by the final mass, and you get delta v, or Change in velocity, then, calculating losses for air drag and gravity, you can figure out how much fuel you have to expel to gain a certain amount of speed.

[@bruno151506]

"SIMPLIFIED"

[@xbutterguy4x]

Wait I thought ksp was everything to rocket science, and this is just the BASICS? I have mild ADHD and got lost when started mentioning mass * acceleration

[@adamweishaupt3733]

There's a reason rocket science is used as a metaphor for anything confusing.

[@CoolestAdventures]

Great video

[@supercoolcow100]

Sound (pressure) waves need a medium to travel through. Inside space shuttle: pressurized air serves as the medium. Outside space shuttle: empty space (no medium)

[@danielalexander9982]

Yes, very basic, showing the very basics without any addition with calculus. In order to calculate all of these parameters you must take into account many different changing aspects. 9.81 is always decreasing as the rocket increases its height, as well the mass in both Gm1m2/R^2 and m2*a are both changing. As well the rocket does not travel in a straight path, in order to orbit a rocket has a trajectory of a shape close to the parabola to reach the proper direction, in which the final velocity would be reached byy a ever changing acceleration based on the vector of the changing directions of force. So much is left out of this, which makes sense seeing as adding in all the calculus in order to fully explain it would be impossible to explain in a minute physics. This is bottle rocket science.

[@danielalexander9982]

Daniel Alexander Also the exhaust of a rocket is not just liquid and it doesnt exit with the same volume, you are only able to calculate based on the use of fuel from inside the rocket seeing as once it exits it is near impossible to measure

[@danielalexander9982]

Daniel Alexander Oh and R isnt just kg, its kg/s! Before he specifically used m-R*t, where R x t is equal to kg. I feel as if this episode was half assed, not trying to be a troll but if you are trying to teach the basics of something extemely advanced please at least get the basics right.

[@marcovillalobos5177]

Maybe you should post a video or write the proper equations with all this corrections.

[@Roman-us2fp]

Basic rocket science is an oxymoron.

[@Gaehhn]

I never expected to see FreddieW in a science video

[@gabiailincai]

No, it doesn't need to be compressed, it just needs to be pushed out with high enough force, like letting liquid out of a syringe, except much faster. Air or gas, however can be compressed withing the container and when the opening is, well, opened, the air has more room where to go to and decompresses while getting out, thus taking up more space and propelling the rocket.

[@graemeroach8550]

why did I watch this, my 6th grade mind is broken

[@KrockDealer]

RoachBeast all you need is a week of physics classes to understand this. Seriously he makes it really easy to understand if you have little knowledge in physics

[@Tohm-kp2wv]

RoachBeast same

[@HiepTon94]

At 2:49 - Shouldn't the (-Ve+V)? instead of -V At 4:21 - Shouldn't the unit of R is kg/s? kg per second instead of only kg Thank you for making the video but it would not help at all if it contains errors.

[@willnewman9783]

Hiep Ton welll yes, but he said that it was going for 1 second, so R=Rt and Rt is the amount of mass

[@HiepTon94]

oh, my false. Thank you.

[@maxef0rt]

Hiep Ton No, it is (-Ve-V). Acceleration = Change in velocity/time The initial velocity was equal to V. Final velocity is (-Ve) since it is going in the opposite direction. So, change in velocity = final velocity - initial velocity = -Ve - V Therefore, acceleration = (-Ve - V)/t

[@masterm25]

9.8 m/s^2 at 45°32'33" Latitude. Moving towards the equator it is less, because of the centrifugal force of the rotation of the earth (being least at the equator), and greater towards the poles (being greatest at the rotational poles). So the gravity we experience is anything but constant and 9.8 is simply the experienced gravity at a relatively arbitrary latitude of the earth.

[@Marioguy57]

This is going to help me for my height school projwct! Thanks!

[@sleazymeezy]

C'mon guys, it's not music theory

[@huyanhle]

A small research rocket of mass 250kg is launched vertically as part of a weather study. It sends out 50 kg of burnt fuel and exhaust gases with a velocity of 180 ms-1 in a 2 s initial acceleration period. (a) What is the velocity of the rocket after this initial acceleration? (Answer v = 40 ms-1) (b) What upwards force does this apply to the rocket? (Answer F = 4500N) (c) What is the net upwards acceleration acting on the rocket? (Use g = 10 ms-2 if required) (Answer a = 10 ms-2)

[@billysgeo]

I got 4,7 liters too, but how did you get the speed???

[@UjjwalDubey1994]

great one!!

[@joshhyyym]

A velocity is the distance traveled per unit time, if you multiply a velocity by a time you get a distance. If you multiply a velocity by one second, you get a distance that is equal to the magnitude of the velocity. ie if you are going 4 m/sec for one second you will have gone 4 metres. :)

[@jcjobin]

depends what you used as units, for example cm^2 for area, kg for mass etc

[@StarkRG]

No, they're still loud there too but in order to hear it you'd need to be within a medium with enough density to carry the compressive sound waves. Since most of space is extremely non-dense the places with enough density would be inside the rocket or inside the exhaust. I suggest inside the rocket.

[@nmajamaki4]

I'm in 7th grade an understand this. If you don't quite get it, watch it again, it helps for me during more complex physics vids.

[@NoActuallyGo-KCUF-Yourself]

See 4:05 - 4:10 "in one second." The volumetric flow rate is given in assumed units of -per-second.

[@769270865]

It is simplified I watched three time and I start getting it

[@user-qb4ke6gm5b]

Awesome!

[@nullcypher]

this is very exciting.

[@netherar]

AWESOME!!!!

[@92Gameface]

HGTTG gotta love it

[@Desollet]

A question like this was on my physics diploma. It's nice to know that I did it correctly even though I was guessing : D

[@ColordHitmarkerz]

im also 15 and although im not a physics nerd and have no experience with physics, i have actually started understanding these videos more and more. Things start to make sense and i find my thirst for knowledge increasing after every video. although i most definitely will not be majoring in physics, i plan to stay with a mathematical course throughout highschool and college considering i have natural talent in those areas. I may do college courses for fun if i could fund them.

[@sk8terkyd326]

Damn 10 years ago

[@sk8terkyd326]

I'm also like that, I want to learn college things that aren't my job but it would cost money

[@DanatronOne]

Those are some insane fins on that rocket...

[@haylingpara]

Excellent...

[@aeroscience9834]

You should do more rocket science

[@niallsaunders5689]

because with rocketeering is pushing against air which obviously is hard to push against so some of the energy from the rocket will just push air out of the way whereas a ladder allows for most of the energy to be transferred to pushing you upwards

[@TheCreeperCrusher]

Thanks!

[@Mackoloco]

gravitational constant, its the acceleration everything on earth is submitted too (we are all accelerated at about 9.8 m/s^2 towards the center of the earth) so g is approximately equal to 9.8

[@Jacksucksat]

im for the Uk and in 6th form which i think is a lot older than you and i have only just learnt about mechanics and some of these forces and equations so dont expect to learn them anytime soon :3

[@cheguevaraisgod]

You are working at the perimeter?!?! I go wo UWaterloo! It would be amazing if you had a meet up at the university or something! It would be great to see you!! see ya around!