SCIENCE CLASS #6- What if Everyone Flushed their Toilet at Once?

Mark Rober

1,4 млн переглядів243

    Let's talk about pressure! I WILL DO ONE FINAL CLASS NEXT WEEK, MAY 6TH!
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    Опубліковано 9 місяців тому


    1. Mark Rober

      Thanks for coming to class!! I WILL DO ONE FINAL CLASS NEXT WEEK, MAY 6TH!

      1. John Gamble

        @RiverTiger767 air pressure changes.

      2. Cubiside


      3. John Gamble

        I want to see an elephant in highheels......

      4. BossyQueen


      5. BossyQueen

        @The Person cool

    2. Elliot Boepple

      His enthusiasm is contagious.

    3. George A

      If all toilets flushed at once, it would not make a dent in the Swamp.

    4. Santiago Saeijs


    5. Jerry D

      What’s under the hat? He always has one on.

    6. Inga Butler

      if you were my teacher, I would want to stay even more in your class, this dude deserves an award

    7. Jyotisko Sengupta

      School Science Class: Boring... Mark's Science Class: Interesting!!!

    8. Caden TheYoutuber

      the biggest crossover in history

      1. StopMotion Guy

        Why are you watching this now.

    9. Eleanor Stanford

      You’re too adorable

    10. Sir Lloyd Classroom

      Can you do an experiment or a simulation of a low pressure then it becomes a typhoon.. Iike to share it to my students for the subject environmental science and the topic is natural disaster.. And what happens when there is no plants or trees in the whole world. The question is what is the time taken to consume the oxygen and becomes carbon dioxide? Thank you sir

    11. Rock N' Roll True Stories

      man i wish you were my physics teacher. Mine made us watch discovery channel each class and i literally learned nothing. Probably explained why i almost went on to almost fail engineering physics in college

    12. Rugby Mad Aunty

      So is the movie flushed away real or not real? 😂😂

    13. Laura Alagia

      Premier League

    14. Paul Jones

      you inspied me to get into enginering

    15. Fishybroboi

      Who else really wants mark to teach there science class

    16. Nina P

      This was actually a question ive been wondering for a long time lol

    17. Ken Allen

      Don’t ask why I clicked on this video....

    18. Ruben van Maanen

      Like its useful for people who dont understand this easily, but once u understand, its boring

    19. Ruben van Maanen

      Do this again plsss

    20. lan3


    21. David

      Put a Democrat in before you flush.

    22. WizMasterT

      Me After Watching This Stream: I wish Mark Rober is my new Science Teacher.

    23. Pinnacle Roofing

      unless the elephant is potty trained, i pick the woman

    24. oofley

      So this is the science behind cutting implements. Cool.

    25. Boojum Snark

      everyone already knows that ... that's exactly what happens during Super Bowl commercials ..

    26. BeautifulFireflies

      This video is so underrated 2,874 comments 1,369,659 views ??? Where are all the Mark Rober fans?

    27. Abejero ivan Ivan Abejero

      Welcome to science class

    28. Robert Sloan

      Can yo do more activitys with nature like the squrell course.

    29. Imman Playz

      I wish my teacher is like you .

    30. Boogieman

      Hes that one teacher that you genuinely get sad when he yells at you

    31. Coach Wilson

      The Super Bowl halftime flush

    32. Dima Mura


    33. ypr figth

      Ah yes the Moment when you jump put of a Parachute

    34. Ankur Panda

      UKup recommends me the weirdest of all wonders.

    35. Colin Richards

      All the sewer workers would be drowned!

    36. Adeum Deus

      I would think nothing. When watching shows like Dirty Jobs, it seemed that the sewage systems, even for large cities, was just a little "stream", if you will, of sewage flowing down a massive pipe. My guess would be that, even if every toilet in New York was flushed at the same time, the different paths sewage takes to reach the sewer would mean the load is spread over a pretty large area, and so it wouldn't just suddenly be a gushing torrent of sewage. Additionally, I would imagine sewage systems have redundancies and overflow lines to keep the system from blowing up. I remember when the giant fatberg was removed from a London sewer. Obviously that sewer line was not the only line, or else the entire community around that blockage would have backed up and wreaked havoc. But they didn't. Water might take a bit to refill, particularly in very densely populated areas, but plumbing is "primed" already (that is, my toilet tank already contains water for the next flush).

    37. ayub ahmed

      the best phy teacher

    38. Quazie Wabbit

      Something to think about: A blond in high heels might wreck your floors, but an elephant in the living room will destroy your entire house, because you know without a doubt, it will see a freak out and run!

    39. Renata

      Does anyone know that this actually happened in NY right after the series finally of mash. They experienced a huge loss in water pressure & a water shortage. You're welcome.

    40. Wrapped Goods

      Random thought: Stars consist of tight energy force. They don't consist of pressure.

    41. super hola

      Zac king skit

    42. Jay Brodie

      The biggest question here is who did he borrow those heels from?

    43. S B

      So when you get shot, you need to drink water and see if there are any leaks?

    44. M. Thomas Brown

      I can tell you what happens when all the toilets in one high school flush at once. And it wasn't pretty.

    45. ME

      Did the elephant clean its feet before walking on the floors? I would have added food coloring to the liquid stuff so it shows up better on camera. You did a great job on this.

    46. Brad Jones


    47. Melody Mathilde

      Mark Rober is keeping me sane tbh

    48. User 5.56

      I wish my teachers teached like this in school i would of learned more & not fell alseep looking at numbers in a book

    49. Heth Richardson

      When I was a kid we used to do a thing where the biggest guy in our group would lay flat on the floor & then we would position ourselves with 1 person at his head, 1 person at his feel & two people either side of him with 2 just below his shoulders & 2 people just below his butt. Then we would just use the pointer & middle fingers on both hands & lift him up off the ground. Pretty cool.

    50. Lexi Anderson

      I would stay in school all week if he was the teacher!

    51. Man in the Park

      Also, you put the tape on top of the nail/balloon thing different for the 2 than for the 12. For the 2, you put the tape all the way near the edge. For the 12, you placed it further towards the hinges. That can change the outcome of your experiment, right?

    52. Man in the Park

      Your question was “which would you let into your house” not “which would you not let into your house”, right? I think my understanding of your solution was lost in translation.

    53. XXXDeathByFartsXXX

      You make me want to become smarter. My brain injury says otherwise.

    54. linoslovely

      if only my science class was like this.

    55. Julian Thurmes

      What if the sewer got full

    56. John Wayne

      Oh kay! Live is never perfect. You handled it perfectly.

    57. Andy Mandura

      Why is the sanitary drain conected to the storm drain. gross af

    58. Edwin's nation

      Fakers be like OMG1!1!1!1!1 MARK ROBOR DIED

    59. Charles Torres

      and thanks

    60. Fire Gaming

      When I first watched one of your vids is when I realized I wanted to go to college for robotics

    61. Phomello Jessie

      Hearing Mark's Clue 1 and asking yourself...How the heck does this involve tiolets?😂

    62. Jeremy Patterson

      So what about everyone taking a shower at the same time.... I feel like that happens a lot ....

    63. Dante Wallin

      I feel like im learning the same amount here or in some cases more then in school physics. You have inspired me to study science and engineering. Im from sweden so the spelling might not be right.

    64. Andrew Henshaw

      The thick jumper? Sweater? really helped too!

    65. The freedom factory

      vieuwer: "what happens if you flush all toilets at the same time?" mark: "someone's gonna sledgehamer a piece of concrete on my chest while I sandwich myself between nailbeds." vieuwer: "what happens if everybody switches the light on at once?"

    66. SavageLittleArms 2.0

      why is this man not my science teacher?

    67. Aahnik Biswas

      that bed of nails was so cool

    68. Playlists HERE

      C'mon to whom is Mark the best is telling about area of the pizza 😂

    69. Trioner Expeliozias

      Idk what kind of red rover you are talking about but that Is not like what I know

    70. Ratu Syifa K.M

      i want mark to be my physics teacher

    71. TheMajorLee

      God Paul G. Hewitt is great.

    72. Patrick Guy

      I wish you were my teacher

    73. RoRoKing

      Markkkk, can u be my science TEACHER?

    74. hola 1234


    75. Bryant Sánchez

      The right equation for the examples with the water tower and the water bottle is P=h*gamma (Hydrostatic Pressure) which it depends on the height of the water surface multiply to the specific weight of the fluid.

    76. Charles Torres

      mark you are asome

    77. john smith

      but the elephant's feet are probably dirtier!!!! :(

    78. Bernadette Jeffers

      But the elephant only has weight on the outside edge of his foot

    79. Lok Sang KEE

      Does anyone actually noticed that there some small holes in his hoodie


      As always Mark, great job.

    81. Angelina Peralta


    82. SmallSir

      Well, maybe where you live, ut where I am everyone has their own little sewer thing in the basement. When it gets full, then it goes out to the street. Not to much will happen here, though.

    83. Vivek Mishra

      Who is here in the month of December 😁

    84. Knockbacknemo


    85. Fernanda Castaneda Martinez


    86. chris conklin

      that is gross it would be terible if your washer had somones waist on there clothes 🤢🤮

    87. Lothar Arywuen

      i FREAKING love ur science classes..greetings from Germany :)

    88. Jasper Byrd

      Hmmm yes every toilet flushing in the world yes yes

    89. eleoel eleoleo

      The guy is cute

    90. Scott Kelso


    91. Harlie Brunson

      thanks dude

    92. Kaan Aşan

      he is actually bleeding real bad but we cant see under his hoodie

      1. Casey Kipfer

        what do u mean bleeding?!?!?!?!

    93. Katie Leishman

      How do you make lights

    94. Jai Adarsh

      Your reincarnation of the classes are here!!!!!

    95. ASHES_99

      i skipped school for this ... It was a good choice

    96. Annmarie Roberts

      Kyk yky tykyykyy tkt kyykykykykykyk yyktykykykykyky kwas ykktk yk tk tk jk tkt kyk yktk yyktkykykyykkyky kykkk yktkykkyy kykykkkykykykykykytkykyu

    97. Shawn Fontenot

      I wish he was my honors science teacher

    98. Rylan Pallow


    99. ReznoV Vazileski

      Doesn't the funnel technically have a lower output pressure because Bernoulli's law states funnels as a high friction coefficient? :p Way out of the scope of the video, but I just wanna confirm if I recall this correctly lol

    100. Bhakti Pethani

      I don’t understand science when other people explain it but when mark does, it makes science more fun and easy