SCIENCE CLASS #2- Does Farting Make You Weigh Less?

This is a juicy one. 70% people get this one wrong. I stream science LIVE M-W-F 1pm PT.



  1. Mark Rober

    Mark RoberPred letom

    I stream science LIVE M-W-F at 1pm PT. Thanks for being here!

  2. Johny Hoare

    Johny HoarePred 15 dnevi

    By making the metal less comoact

  3. Malakai Thompson

    Malakai ThompsonPred 3 meseci

    I think the shape of the bottom is why it doesn't float - Malakai (6)

  4. Isu

    IsuPred 3 meseci

    you are welcome :

  5. Balboa Rocky

    Balboa RockyPred 3 meseci


  6. Kittenz Iwnl

    Kittenz IwnlPred 5 meseci

    @William Pantel look no o

  7. tall32guy

    tall32guyPred 3 dnevi

    So funny! Mark you are such a goofy (and cute) guy! :)

  8. Lindsay Thiel

    Lindsay ThielPred 11 dnevi

    Is that how boats are able to stay up mark?!!??!??!!!?

  9. Brian Lane

    Brian LanePred 14 dnevi

    I have a hard time believing the answer is quite this simple. You aren’t taking into consideration the compression effect your body might have on the gases inside of it. It might be negligible, but, it surely counts for something

  10. Milton Sierra

    Milton SierraPred 15 dnevi

    We did this in sixth grade everything he did in clue one we learned in sixth

  11. mod miiwii

    mod miiwiiPred 16 dnevi

    I played does it float or sink with my moms phone and now she is mad at me for some reason. I told he it was an important scientific study.

  12. Eu C

    Eu CPred 19 dnevi

    Maybe you put a can over it to make the heavy chunk of metal float? Just guessing.

  13. Eu C

    Eu CPred 19 dnevi

    Oh my gosh I was wrong XD

  14. cassandra

    cassandraPred 19 dnevi

    It certainly feels that way.

  15. Alex _ IsBroken

    Alex _ IsBrokenPred 20 dnevi

    7:15 Is it just me or did he say something else that wasn't "ships...?" :'>

  16. jamcdonald120

    jamcdonald120Pred 22 dnevi

    29:30 I have a 20 year plan, but I am the only one I know who does, and I didnt come up with it until my last year of college.

  17. jamcdonald120

    jamcdonald120Pred 22 dnevi

    3:55 make a boat?

  18. Jory Potts

    Jory PottsPred 22 dnevi

    Great job Mark you make it easy for us to watch thank thank you thank you

  19. 林宸毅Jayden

    林宸毅JaydenPred 23 dnevi

    so there are no gasses

  20. J.P. Sayer

    J.P. SayerPred 23 dnevi

    This is a class where you teach the concepts mass vs weight

  21. Charles Brouillette

    Charles BrouillettePred 23 dnevi

    Every time mark said ocean of air I kept thinking of the song “ astronaut in an ocean”

  22. StupidSwine

    StupidSwinePred 24 dnevi

    "its not a skirt its a skilt" ☠️

  23. ShadowClaw357

    ShadowClaw357Pred 28 dnevi

    Mark Rober would be the best physics teacher everrrr! I wish I could have him

  24. Stewka

    StewkaPred mesecem

    By flattening the metal and widen the area?

  25. Quintin Sargento

    Quintin SargentoPred mesecem

    I farted 11 times during this video. Too bad I didn’t lose any weight :(

  26. Marky Zukowski

    Marky ZukowskiPred mesecem

    Gas is a certain type of air so it weighs nothing so no

  27. Miss Gnoamer

    Miss GnoamerPred mesecem

    Expelling flatulence causes the human body to change volume… less gas equals less volume… therefore, as gas is released the density of of the human body increases… so yes, you weigh more after you expel flatulence.

  28. Kenza Rezyarifin

    Kenza RezyarifinPred mesecem

    Best science teacher

  29. Comit

    ComitPred mesecem

    I actually got 100% on the "will it float" segment!!

  30. dirtrider88

    dirtrider88Pred mesecem

    0:25 wonder how many people caught the joke. and while im 25 seconds in im gonna say no, it makes you weight more

  31. Kester

    KesterPred mesecem

    I've been telling people this for years and they rarely believe me! I'm so glad I can finally back that up by showing them this video!

  32. Internet Troll

    Internet TrollPred mesecem

    Make a tin foil boat

  33. Internet Troll

    Internet TrollPred mesecem

    Or does losing some hot air make you weigh more?

  34. Eashan Kakulla

    Eashan KakullaPred mesecem

    8:07 is float.

  35. killakira12

    killakira12Pred mesecem

    So we kinda like balloons? If we let the smelly air out we become heavier. Just like balloons.

  36. Cali Foxworth

    Cali FoxworthPred mesecem

    Are you live right now?

  37. Glenn Quagmire

    Glenn QuagmirePred mesecem


  38. Frost

    FrostPred mesecem

    so if fart a tons of time in a ballon its gonna float !!! lol

  39. killakira12

    killakira12Pred mesecem

    Yes lol

  40. Red Gum

    Red GumPred mesecem

    Depending on the liquid or gas you are in

  41. Andrew Walkington

    Andrew WalkingtonPred 2 meseci

    It doesn't matter how many life jackets you put on some people, you can't make them less dense...

  42. Robin Kessler-Braun

    Robin Kessler-BraunPred 2 meseci

    i love your videos

  43. Herb Molina

    Herb MolinaPred 2 meseci

    It floats

  44. Jim Shepherd

    Jim ShepherdPred 2 meseci

    Technically, "weight" is mass x gravity. When you fart, you lose some mass, ergo you weigh less. What you're actually saying here is that we become more dense when we fart, and therefore the resultant force of gravity vs buoyancy is greater in the direction of buoyancy, hence why the scales would show you as "heavier". But you're still losing weight when you fart.

  45. YourBuddyYasin

    YourBuddyYasinPred 2 meseci

    Mark, thank you for this video because you answered my 7 year old minds question. Keep on going dude!

  46. Pék Backer

    Pék BackerPred 2 meseci

    3:25 lol :D

  47. Braxten Rager

    Braxten RagerPred 2 meseci


  48. Evan Sisco

    Evan SiscoPred 2 meseci

    more mass via the shape

  49. Catal

    CatalPred 2 meseci

    Best Teacher Ever

  50. Angel Jonguitud

    Angel JonguitudPred 2 meseci


  51. Salim Ibrahim

    Salim IbrahimPred 2 meseci


  52. Keren Liila

    Keren LiilaPred 2 meseci

    These videos are short My science class last 70 mins

  53. Abigayle Gaming

    Abigayle GamingPred 2 meseci

    This was 1 year ago

  54. Daniel Reads

    Daniel ReadsPred 2 meseci

    Thanks so much for the life advice too!

  55. Steven Thompson

    Steven ThompsonPred 2 meseci

    Oh that’s why wrestlers grunt a lot, they are trying to fart so they can weigh more to gain some power over their opponents

  56. Marcus Wildey

    Marcus WildeyPred 2 meseci

    It’s funny that yes you weigh more but you have less mass just think about that for a moment

  57. Natalie Mishoe

    Natalie MishoePred 2 meseci

    I am 43 and loving this. I wish I would have had a teacher like him. Mark make sure you do stuff like this in your high school class room bc it makes all the difference

  58. Miss Wendy Jane

    Miss Wendy JanePred 2 meseci

    I don't want to eat a lot of beans to find out - can someone just confirm the answer?

  59. Federal Noob association

    Federal Noob associationPred 2 meseci

    My guess for the "Why the sky is blue" The sky reflects off the ocean and probably has to do something with atmosphere changes it I think.

  60. Greg Sullivan

    Greg SullivanPred 2 meseci

    My employer coerced me into teaching an evening class at a local JC. The subject was Printed Circuit Board production - drilling and routing. I dreaded the thought. Thankfully I had taken a speech class in college so I at least had a clue on how to talk to 45 people. It turned out that I actually enjoyed the "give and take" between myself and the students. It was more rewarding than I expected.

  61. Jesus Stout

    Jesus StoutPred 2 meseci

    Awesome educational video

  62. Reptilian Apple Salesman

    Reptilian Apple SalesmanPred 2 meseci

    Nursing home answer: Ethel! Where are my teeth?!?

  63. Heather Smiliekiwi

    Heather SmiliekiwiPred 2 meseci

    Except a Ted talk tells you fat leaves your body via air. I don’t know who to believe...

  64. Donald Duck 82 2.0

    Donald Duck 82 2.0Pred 2 meseci

    Its grown up so fast 1 year

  65. Dragon Tail

    Dragon TailPred 2 meseci

    Gonna hold my farts from now on

  66. Josh Wallis

    Josh WallisPred 2 meseci

    So what was the answer to the title of the video?

  67. Ryan Hannigan

    Ryan HanniganPred 2 meseci

    The fine step-aunt fortuitously exercise because wrinkle virtually step outside a elastic carrot. nonstop, talented babies

  68. Mike 808

    Mike 808Pred 2 meseci

    "The earth moves underneath ever so slightly" when jumping, - according to the model it moves at 15° an hour which would mean it is rotating at about 1000 miles an hour at the equator. I guess ever so slightly is subjective

  69. Giorgi Tsiklauri

    Giorgi TsiklauriPred 3 meseci

    But are farts not under compression in the bowel?

  70. fulSTakk

    fulSTakkPred 3 meseci

    I mean, give this man what he needs to become a teacher. He'll be the coolest high school teacher in North America.

  71. A UGUST

    A UGUSTPred 3 meseci

    where's one of your 1st youtube videos you said you would put in the comments below (25mins 22secs)

  72. adriancombe

    adriancombePred 3 meseci

    That is totally not where I thought you were going with this, right up to the end. I was thinking in terms of how the flatulence originates, which is decomposing organic matter. Before it decomposes, it is solid. Once it becomes gas, it can leave the body. So if you compare the weight before the decomposition to the weight after, all other things being equal, you weigh less. But if you don't measure weight until after the digested food has decomposed, then of course the buoyancy is the driving principle.

  73. Federal Noob association

    Federal Noob associationPred 3 meseci

    Ayyyyy welcomd

  74. Nicoolio

    NicoolioPred 3 meseci

    I would relive the horrible experience that was high school just to have Mark Rober as my physics teacher

  75. TheLostArceus

    TheLostArceusPred 3 meseci

    He had the chance to throw rose in the ocean and didn't. Idk what to make of this.

  76. Randolph Torres

    Randolph TorresPred 3 meseci

    OOOPS Just gained some weight!! So that’s why girls don’t fart.

  77. moneyblackblood

    moneyblackbloodPred 3 meseci

    This is awesome! Often my farts feel highly pressurized. Is it possible that if I packed enough fart into a small colon the density of said fart would be greater inside me than that of the air around me?

  78. jeff buck

    jeff buckPred 3 meseci

    will the results b the same in a vacuum?

  79. Nathan Hazzard

    Nathan HazzardPred 3 meseci

    to make something nutraly boyent cant you just caculate the desity of both the block of wood and the bucket of water (mass over volume) and make them the same

  80. Boni S

    Boni SPred 3 meseci

    Hahahaha 20:48 😂

  81. Kyla parkinson

    Kyla parkinsonPred 3 meseci

    No farting does not make you weigh less, because a fart is a gas which is just stored inside your stomach so when you fart gas weighs nothing becuase its almost air but they have differences but air weighs nothing and thats onr thing gas and air have in common. So technically no farting does not make you weigh less

  82. michael revels

    michael revelsPred 3 meseci

    Man I'm still watching this video to see what he says, geez man a simple yes or no would be great. I'm assuming mathematically speaking it has to make you weight less it's less of something less of something means less you, right.

  83. Khalid Ahmed

    Khalid AhmedPred 3 meseci

    your the best youtuber

  84. Patricia Anguiano

    Patricia AnguianoPred 3 meseci

    Mark: it isn’t that easy Me: OH NO! ITS IMPOSSIBLE!

  85. Standard Built

    Standard BuiltPred 3 meseci

    POV: You yelled at a dude who worked for NASA because he used weight instead of mass for density. Then seconds later he addresses it.

  86. Theron Trickshots

    Theron TrickshotsPred 3 meseci

    I always watch one of these videos to help encourage me when I'm cycling at home

  87. Zanna

    ZannaPred 3 meseci


  88. Zanna

    ZannaPred 3 meseci


  89. Zanna

    ZannaPred 3 meseci

    make a metal boat

  90. Zanna

    ZannaPred 3 meseci

    You will weigh more.

  91. Mullvaden83

    Mullvaden83Pred 3 meseci

    Im gonna go to school again just to have Mark Rober as teacher. XD

  92. 1K subbs with awesome videos

    1K subbs with awesome videosPred 3 meseci

    Depends on how many farts you take out.While only 1 fart weighs 0 pounds, a lot more will weigh more, and while the farts are inside you, you weigh more.When you get them out, that weight gets out, and you weigh less.

  93. Speedcuber975

    Speedcuber975Pred 3 meseci

    So before even clicking on this video I had a whole thought process of “well considering that gas is trapped inside you, it should technically be helping you in the direction of being lighter the same way helium makes a balloon go up instead of weigh more. So getting rid of it technically makes you weigh more, Like a balloon loosing some of its helium wouldn’t float as high. This comment was written before watching the video at all so we’ll see if I’m right.

  94. Deval Maheshwari

    Deval MaheshwariPred 3 meseci

    I was waiting for lord watermelon to appear

  95. Carmen Yeung

    Carmen YeungPred 3 meseci

    I'm 32, and I just had a WHAT?! moment, Thank you.

  96. OpticFN 父

    OpticFN 父Pred 3 meseci

    This guy explains stuff more clearly than my Science teacher....

  97. Epic Boi

    Epic BoiPred 3 meseci

    What's making him not pop is that there is no idiots screaming in class.

  98. Duke Pfeiffer

    Duke PfeifferPred 3 meseci

    Make a bubble of metal it will float

  99. Ebad Rahman

    Ebad RahmanPred 3 meseci

    Tin foil boat Edit: ye I got it, mad

  100. Roblox player

    Roblox playerPred 3 meseci

    Awwwe mark loves playing with his dolls lol

  101. zZILLAa 2

    zZILLAa 2Pred 3 meseci

    #1 Density 2:30 #2 Boiancy 13:10 #3 Gas is less dense than air. 17:10 #4 summerisation 17:39

  102. hoon tae

    hoon taePred 3 meseci

    The agreeable mistake largely burn because capital morally warm following a joyous population. warlike, insidious afghanistan

  103. ImJustSnipeHunting

    ImJustSnipeHuntingPred 3 meseci

    I totally thought this was live right now.

  104. ImJustSnipeHunting

    ImJustSnipeHuntingPred 3 meseci

    Why do witches float?

  105. ImJustSnipeHunting

    ImJustSnipeHuntingPred 3 meseci

    Make a boat

  106. Isu

    IsuPred 3 meseci

    i just did density like 2 days ago in my school and my teacher couldnt explain me that in 60 mins but mark explained to me in 10 mins:)

  107. Isu

    IsuPred 3 meseci

    if he was my teacher i would be willing to go to school