Secrets to measuring a piece of paper - Numberphile

  • Published on Oct 11, 2017
  • When Cliff Stoll sets your homework, there's always an extra lesson.
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Comments • 1 211

  • Aqilaizuddin Ismail
    Aqilaizuddin Ismail 17 days ago


  • Pallavi RoyC
    Pallavi RoyC 19 days ago +1

    This is the best way to teach he makes you think :) love his enthusiasm and love of the subject

  • redbeam_
    redbeam_ 2 months ago

    So that was a Parker-ruler!

  • ceruchi
    ceruchi 3 months ago +1


  • Oculus_Official
    Oculus_Official 3 months ago +1

    I love this guy!

  • Danielsan B
    Danielsan B 3 months ago +1

    He is the iconic mad, wacky, kookie, crazy, zany, hand-waving, screechy voiced scientific/mathematician.

  • Jannatul NAyeem
    Jannatul NAyeem 5 months ago

    Can you make a video of Qualitative measurement or Psychological measurement and measurement systems? Please...

  • Sabrina Islam
    Sabrina Islam 5 months ago

    HI reincarnated Einshtein

  • What Is dis
    What Is dis 5 months ago +1

    one of his books is named "Automatic Sprinkler Systems for Residential Occupancies Handbook", and I bet he read it "for fun" :)))

  • MumboJ
    MumboJ 5 months ago +1

    Immediately distrusted the Ruler provided, but didn't pick up on any of the other traps.
    Also, I assumed an A4 size, which I know to be an irrational number, and therefore not precisely measurable with a standard ruler.

  • Ranno Valk
    Ranno Valk 6 months ago +1

    This guy just managed to troll a bunch of 8th grade students... Oh, and also, if I get an Imperfecto ruler, I am gonna troll some classmates who will always borrow my ruler.

  • Serge SpeaR
    Serge SpeaR 6 months ago

    Этот дед, будто, сам в школе не учился. Там и похлеще задания дают… И, несмотря на глупость задания, всё же ждут от ученика правильного, конкретного ответа. Так что он тех восьмиклашек не удивил, ни своим кривым листом, ни линейкой с двумя одинаковыми значениями. Ученики, лишь в очередной раз поняли с какой дичью будут иметь дело во взрослой жизни и в ответ на эту дичь они будут вынуждены давать правильный, конкретный ответ.

  • Dingus
    Dingus 7 months ago +1

    This guy done went and Stoll my heart.

  • Enlighten
    Enlighten 8 months ago +1

    Numberphile, this guy is the best, MORE VIDEOS WITH CLIFF!

  • Alex Zverev
    Alex Zverev 8 months ago

    Was that a Parker ruler?

  • Bridget Golubinski
    Bridget Golubinski 9 months ago +1

    Cliff is such an interesting man

  • blackkittyfreak
    blackkittyfreak 9 months ago +1

    This guy is amazing! I wouldn't miss one of his classes for anything!

  • Aaron Scott
    Aaron Scott 9 months ago +1

    Sir... I ate my imperfecto ruler...

  • dejwidkoperfild
    dejwidkoperfild 9 months ago +1

    This guy tilts me.

  • Alon Ben Dov
    Alon Ben Dov 9 months ago +1

    He is amazing!

  • amm biotronik
    amm biotronik 9 months ago

    Anyone else notice there's only 9mm between the two 17s on the ruler?

  • General Grievous
    General Grievous 9 months ago +1


  • some dude
    some dude 9 months ago +1

    I'd love to have this guy as my math teacher

    MOHAMMED ZUBAIR 9 months ago +1

    So, what's the secret to measure the area of the paper?

  • RebeccaS1231
    RebeccaS1231 9 months ago +1

    What an evil problem :P

  • Dat1AsianDude
    Dat1AsianDude 9 months ago +1

    Use displacement

  • QuasiELVIS
    QuasiELVIS 9 months ago +1

    It's like if Woody Allen was a teacher.

  • Xepscern
    Xepscern 10 months ago

    4:50 dab

  • marco56702
    marco56702 10 months ago +1

    One of the most educating videos I've ever seen.

  • Amanda Chapone
    Amanda Chapone 10 months ago +2

    I wish you were my science teacher... I’m in 8th grade!

  • Kim Kobusch
    Kim Kobusch 10 months ago

    I remember being displeased after an examination where a similar ruler trick was pulled on me. I simply couldn't accept that my answer was incorrect since the math checked out. My teacher later told me that assumptions (like the ones in this video) IS a part of mathematics. Although I get it now, I still felt it was a bit cruel to present students with an incorrect ruler during an examination.

  • malab barik
    malab barik 10 months ago +1

    I love this guy!!!!

  • Portree Mathstutor
    Portree Mathstutor 10 months ago

    The lesson to learn is you can not trust tricksters.

  • anjopag31
    anjopag31 10 months ago +1

    Brilliant. Good advice at the end, too; definitely taking this example into consideration when I apply to colleges in a few years.

  • Erbmon
    Erbmon 10 months ago

    I'm not very educated but if print paper weights 80g per square meter you can just measure the paper and rule of 3 this thing right?

  • Warman Fuzzy
    Warman Fuzzy 10 months ago

    This got philosophical way too fast

  • Brian Holdren
    Brian Holdren 10 months ago

    This teacher is evil! (But super cool!) Re: the holes in that paper, the 16-17-17-17-18... Ruler... 8th graders! (I was in a 'gifted' program as a kid, so we got this kind of stuff all the time, and... FUN!... BUT... C'mon! (Hehe!) cool!1 second ago•

  • Sean Haggard
    Sean Haggard 10 months ago

    His advice on college apps is admirable but in reality, just check the boxes, do your AP classes, get your extra curriculars, and write your essay 1-3-1 use two big words and defend a very PC idea.

  • Sean Haggard
    Sean Haggard 10 months ago +1

    Probably a more profound lesson than anything they learned in college.

  • AcixCube
    AcixCube 10 months ago +2

    Cliff is da man

  • MovingThePicture
    MovingThePicture 10 months ago

    He is an iPhone guy my world just collapsed

  • Silver Arrow
    Silver Arrow 10 months ago

    248 people must of been your students, ultimate bamboozlin

  • Connor Wholey
    Connor Wholey 10 months ago +2

    This man is my favorite.

  • Mazhar Imam Khan
    Mazhar Imam Khan 10 months ago

    I would want numberphile to make a video on this topic LINK:

  • Geral Ferald
    Geral Ferald 10 months ago +1

    Rick? Is that you?

  • Matthew Carr
    Matthew Carr 10 months ago

    Cliff Stoll rules!

  • 1234kalmar
    1234kalmar 10 months ago +2

    It's rare something can burst through my depression. This guy did. :3 He is awesome!

  • Wtfro
    Wtfro 10 months ago

    Only thing i gained from this video is a negative number on the respect value about myself

  • Abhishek Surya
    Abhishek Surya 10 months ago +1

    What an amazing guy!

  • Henk Humberg
    Henk Humberg 10 months ago +1

    I failed many exams in my chemistry studies because I had to know some things that didn't help during the exams. So maybe we need more teachers like him.

  • Axel Stoll
    Axel Stoll 10 months ago

    4:32 it's Rick Sanchez

  • Marc Bartolabac
    Marc Bartolabac 10 months ago


  • Nighthawk
    Nighthawk 10 months ago +1

    well at least none of them went "what's metric?"

  • EnoughSoon
    EnoughSoon 10 months ago

    I like his personalities

  • teleturbo
    teleturbo 10 months ago

    1.21 GigaWatt!

  • Matthew Smith
    Matthew Smith 10 months ago +1


  • kumquatery
    kumquatery 11 months ago

    He is the type of teacher you always hope you get.

  • Alex Dimitrov
    Alex Dimitrov 11 months ago +1

    I've seen this 5 mins of this guy and I love him.

  • proudblackjynx
    proudblackjynx 11 months ago

    How fun. Too bad the American university education and academia are garbage.

  • Andrew Liu
    Andrew Liu 11 months ago +1

    I want this guy to be my professor.

  • MrSuperSteva
    MrSuperSteva 11 months ago +1

    Best video with Cliff ever
    ♡ thank you Cliff

  • hayman taylor
    hayman taylor 11 months ago

    Pizzas don't like to do that.

  • How To Vegan
    How To Vegan 11 months ago

    People say paper is 2d, no the only thing that is 2d is atoms and our point of view.

  • לביא גלזמן
    לביא גלזמן 11 months ago

    Wow. This is awesome.

  • Clark Gray
    Clark Gray 11 months ago +1

    Cliff, you're amazing and a real inspiration.

  • Zeno Phu
    Zeno Phu 11 months ago +1


  • Todd Hensley
    Todd Hensley 11 months ago +2

    “The Cuckoo's Egg”! That’s where I know him from!

  • Tooniis+
    Tooniis+ 11 months ago +1

    yay klein bottle guy is back!

  • gedstrom
    gedstrom 11 months ago

    Back when I was in school, if you questioned an ambiguous statement, you were most likely told to sit down and shut up! They definitely didn't want you to "Think Outside the Box".

  • poiewhfopiewhf
    poiewhfopiewhf 11 months ago

    curb season 9 great so far

  • Ryan Roebuck
    Ryan Roebuck 11 months ago

    Love this.

  • Nabillio96
    Nabillio96 11 months ago +1

    I like this guy

  • Stephen Jones
    Stephen Jones 11 months ago +1

    As an adult, I see the wisdom of that experiment. As a "just tell me the answer" kid, I would have wanted to throw a book at his head.

  • DaTux91
    DaTux91 11 months ago +2

    Where would I be able to get that ruler? I'd love to give this homework to my physics students!

  • Mehrad Mahmoudian
    Mehrad Mahmoudian 11 months ago +1

    This guy is a perfect teacher. he conveys enough enthusiasm so that you feel the thirst of knowledge

  • AnticPosition
    AnticPosition 11 months ago

    How do I buy a class set of those rulers?!

  • Shrimp Bisque
    Shrimp Bisque 11 months ago

    bless this man

  • Knax4747
    Knax4747 11 months ago


  • daniel shmoeli
    daniel shmoeli 11 months ago +1

    If every number times zero equals zero and every number times infinity equals infinity, what is zero time infinity?

  • Dwi Ranu
    Dwi Ranu 11 months ago

    3:25 Not only double 17, the ruler also less 1 mm mark.

  • Parag Goyal
    Parag Goyal 11 months ago


  • Tomas Kracmer
    Tomas Kracmer 11 months ago

    I looked for this ruler on google. Haven't found anything. Does anyone have an image of the ruler, that can be easily printed? Thanks!

  • _CrazyCrafter672
    _CrazyCrafter672 11 months ago

    Could you do a video about the number 672? That would be amazing

  • Epic Tien
    Epic Tien 11 months ago +2

    **goes to my locker to check if my ruler isn’t duplicating numbers**

  • Epic Tien
    Epic Tien 11 months ago +2

    And by the way, here’s a ruler for you 😂
    I love this guy

  • Leiflvr
    Leiflvr 11 months ago

    Is there somewhere I can print off the offset sheet and ruler?

  • GovernmentCritic
    GovernmentCritic 11 months ago

    What is an "iphone guy"?

  • TKnowlesy
    TKnowlesy 11 months ago

    Infectious enthusiasm! Love teachers like this. This is how to make learning fun.

  • Lopo Isaac Fernández
    Lopo Isaac Fernández 11 months ago

    Who is this guy? So funny! :D

  • Simon -PFL
    Simon -PFL 11 months ago

    This guy is straight outta the creed. Nothing is true; everything is permitted.

  • Jayarava Attwood
    Jayarava Attwood 11 months ago

    We must know, we will know. I could not agree more!

  • Helgali
    Helgali 11 months ago

    Just like Doc Brown: kinda crazy, totally enthusiastic. Lovely.

  • Jochem van Pamelen
    Jochem van Pamelen 11 months ago

    I've got a question, but first let me set the scene.
    So, I was calculating the limit of x->4 of (x²-2x-8)/(4x-x²) this would equal -1,5. Of course if x=4 there would not be a y-value because you would divide by 0. So wondered what it would look like if you zoom in on the the point A(4;-1,5). I took my calculator (TI-84 plus CE-T), put in the function and started to zoom in. Eventually I started to see something that looked like random spikes in the line.
    So my question is: why does this happen?

  • rolen47
    rolen47 11 months ago

    For some reason this guy reminds me of Scott Bakula.

  • Bufonidae
    Bufonidae 11 months ago

    what is 1110 to the power of 1111 ?

  • Alan Henness
    Alan Henness 11 months ago

    You are cruel! I love it.

  • larrybud
    larrybud 11 months ago

    He missed a couple of assumptions: Even if you caught the two 17's on the ruler, whose to say the ruler is calibrated correctly? And if you're using the other sheet of paper to check squareness, you better know that your source sheet is also square.

  • fang4643
    fang4643 11 months ago +1

    Great video! Having that sort of mentality can get you into trouble at work sometimes, people just want instant results these days and consider curiosity a waste of time. I just had a shitty day at work because of that and I feel better now knowing there are different people out there.

  • awillers55
    awillers55 11 months ago

    Legend has it that his brain is a Klein bottle