Did Usain Bolt REALLY run 100m in 9.63 seconds?

  • Published on Aug 6, 2012
  • Usain Bolt won gold in the 100m sprint at the London Olympics, clocking 9.63 seconds... but Albert Einstein has something to say about all this?
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  • Science & TechnologyScience & Technology

Comments • 7 022

  • Ambassador Kees
    Ambassador Kees 2 days ago

    IF anything would faster than C, it's clock would show complex time 🙄

  • john edwards
    john edwards 2 days ago

    It was still 9.63 seconds. It was Usain's watch that changed, time itself didn't change. A second is what divides into the Earth's rotation. When Usain was running, his watch wasn't counting seconds.

  • Robbie Stone
    Robbie Stone 5 days ago

    a mathematician may care about accuracy
    but some people just care about averages and approximations

  • michael belley
    michael belley 13 days ago

    If you go at the speed of light, what would happen with the time since it would be the square root of 0 ?

  • Nathan Young
    Nathan Young 19 days ago

    I feel like majority of the viewers came here not because they were interesting in math but just out of controversy from the video title.

  • Craven Theflava
    Craven Theflava 25 days ago

    The time would still be the same, because for Bolt's clock he would still have ran the same time. His clock would both start counting earlier and stopping earlier than the "ring clock". The time it would take for the ring clock vs Bolt's clock from start to finish would be the same. So Bolt would start before the ring clock and finish before the ring clock stopped, but for Bolt's clock the time it took to run the 100m distance would still be the same. The difference being the starting time and finish time. That means it would even out when taking into account Bolt clock started earlier than the ring clock.

  • Selmer Stray-Pedersen
    Selmer Stray-Pedersen 29 days ago +1

    If this is true, then the stadium clock clocked 9,630000000000 exactly.
    That could not be true.

  • nowonmetube
    nowonmetube Month ago

    Has this become a physics channel? 🤔
    (Obviously not, when you look at the upload time)

  • Louis Rouxel
    Louis Rouxel Month ago

    No since he ran it in 9.58 seconds.

  • Fun with Fome Fun run 2

    You could have just said that the more velocity an object with mass goes, the slower time goes for that object lol. Basic relatively

  • Keisermilchbart
    Keisermilchbart 2 months ago

    click bait

  • GoldyLuck
    GoldyLuck 2 months ago

    if he was running against the rotation of the earth.. wouldnt he have a slower time?

  • Sayon 2903
    Sayon 2903 3 months ago

    Wait the the stadium's clock's time was rounded off!

  • Thomas Smith
    Thomas Smith 3 months ago

    I first watched this in 2012, aged 14, a huge athletics nerd but knowing nothing of either Taylor expansions or special relativity.
    I now sit here watching this instead of preparing for my university finals, and realise just how simple it is when you're used to the idea and you've had some practice. So, anyone else watching this thinking 'I have no idea what is going on', there is hope!

  • Matthew Skills
    Matthew Skills 3 months ago

    This video is a big waste of time

  • Greg
    Greg 4 months ago

    This is so ridiculous

  • Badhbhchadh
    Badhbhchadh 4 months ago

    I knew this video would be about that before I clicked.

  • J W
    J W 4 months ago +1

    This only makes sense if he ran exactly 9.63 seconds which is basically impossible.

    • Tim Cuffman
      Tim Cuffman 4 months ago

      +J W Right, but I think the video still makes *sense,* even if it's not strictly *accurate* because it's working from the 9.63 estimate. I think everyone, including the guy in the video, knows that 9.63 is just an estimate, just like a lot of the other figures in the video (like the 5 millionths of a nonosecond figure) are just estimates. If Bolt's clock result were actually more like 3.628576850483583509 or something, then the calculation that the guy did in the video would still apply to the more accurate figure (pretty much) just as it did to the estimated figure.
      So, in short, I think your first comment is better rephrased as follows: "This result is only precisely accurate if Bolt ran exactly 9.63 seconds which is basically impossible."

    • J W
      J W 4 months ago +1

      +Tim Cuffman opps no i meant his result

    • Tim Cuffman
      Tim Cuffman 4 months ago +1

      No, the same principles would apply regardless of what the stadium clock said and even if that clock was precise to dozens of decimal places.

  • Anirudha Kulkarni
    Anirudha Kulkarni 5 months ago

    So does that mean if I m in bullet train therr will be the difference between my watches time and stations time

  • 3Vimages
    3Vimages 5 months ago


  • Patrick Kimani
    Patrick Kimani 6 months ago

    You remind me of my physics teacher. He was always imagining particles moving at speed v while others accelerating at the rate of dv/dt...

  • breadfan262
    breadfan262 6 months ago

    The problem I have with a speed limit of c is that any speed has to be defined by a “fixed” reference point which is arbitrary

  • Miķelis Baltruks
    Miķelis Baltruks 6 months ago

    plot twist - stadium's clock was moving along the leader. So it showed the same as Usain's clock. So all of this is unnecessary! :D

    YASHI KANT 6 months ago

    What about light?? 💡 Think!😕

  • Scott Anderson
    Scott Anderson 6 months ago

    Gorillas run the 100 in nine flat

  • Me Playzz
    Me Playzz 6 months ago

    Thats almost 10 metres per second, wow, i cant even do 2 metres a second

  • Steve Wayne
    Steve Wayne 6 months ago

    the example of your car traveling at the speed of light towards the 70MPH car is misleading. Just because we accept that something cannot travel faster than light does not mean that speeds faster than light do not exist. The car traveling at the speed of light cannot go faster - agreed. The car going at 70MPH can go faster - and the closing speed between the 2 objects is the speed of light +70MPH. Neither car has exceeded the speed of light and neither car is traveling at the "closing speed" therfore your assertion that the closing speed cannot be SpeedOfLight+70MPH because nothing can travel faster than the speed of light is wrong. Besides, watch Star Trek - warp speed :)

  • Sharath Kumar
    Sharath Kumar 7 months ago

    Numberphile, I have a question. So, does this mean that if I move at the speed of light, time will basically stop for me? Or that space will shrink to nothingness? Please tell me, the question is killing me...

  • Guust
    Guust 7 months ago

    Don't forget the time it takes for the soundwaves from the starting gun reaching the ears of the runners and the time before the brain reacts to the signal of the ears. That time totals up to 0,15 seconds 👍🏅

  • John S
    John S 7 months ago

    If we are being this precise, then we would also have to include the fact that during the crossing of the finish line it took time for the light to travel from the (former) position of Usain Bolt to the camera, and that by the time the picture was being snapped, he had actually moved further. There is also the starting mechanism....

  • Trie Haryanto
    Trie Haryanto 7 months ago

    Don't understand what you described. I'd rather just run! 😂😂😂

  • Atraya Bajpai
    Atraya Bajpai 7 months ago +1


  • Justin T
    Justin T 7 months ago

    Got to go fast to stay young

  • Przemyslaw Sliwinski
    Przemyslaw Sliwinski 7 months ago

    What if we put a stadium clock a little higher?

  • Hiba Zreik
    Hiba Zreik 7 months ago


  • Yoda Yoda
    Yoda Yoda 7 months ago

    When you’re that bored...

  • zamazalotta
    zamazalotta 7 months ago

    i'm a simple guy, i see relativity in a numberphile video i hit that dislike button 👎👎👎
    maybe this would be interesting in a parallel universe, but not here...

  • RubyPiec
    RubyPiec 8 months ago


  • Colin Batchelor
    Colin Batchelor 8 months ago

    Way late here, and I'm only being technical because I have advanced experience in the subject, but just wanted to add all times in track (athletics) are rounded up to the next hundredths, so anything from 9.6201-9.6300 would be listed in the official results as 9.63.

  • Stu Pidas
    Stu Pidas 8 months ago

    But which direction was the the track? With or against the rotation of the earth? Sloppy sloppy!

  • Alex Rodriguez
    Alex Rodriguez 8 months ago

    What if the stadium clock read 9.637363837292919272

  • bhrugu rajput
    bhrugu rajput 8 months ago

    2:20 Jake Peralta ??

  • bespacito daily-Raf Pacheco Reacts

    2:21 rare footage of adolf hitler screaming at his soldiers after they lost WWII

  • Sam Nasam
    Sam Nasam 8 months ago

    did he really run 100m?

  • Brad King
    Brad King 9 months ago

    The stadium clock is always rounded to nearest hundredth. So he could have ran a 9.625-9.629...

  • HappyBeezerStudios - by Lord_Mogul

    If he went slightly less then 100m in slightly less then 9.63 sec can't the extrapolate that he would've reached exactly 100m after exactly 9.63 sec?

  • Bob squash
    Bob squash 9 months ago

    Nah he jogged it

  • Fraud Samaritan
    Fraud Samaritan 9 months ago

    what do you mean track shrank?

  • Venkatesh babu
    Venkatesh babu 9 months ago

    Ratio of v square to c square meets the qualifiers of space exchange. The limiting factors.

  • BillNGX
    BillNGX 10 months ago

    Surely his watch would tell the time?

  • Paul George
    Paul George 10 months ago

    Nah he ran 9.58

  • James Latimer
    James Latimer 10 months ago

    He wears a cheap Rolex made in Japan

  • Tim Owen
    Tim Owen 10 months ago

    Surely a 0.2 second reaction delay would bring it down to 9.43 seconds of actual sprinting. Who cares about your nanoseconds? Leave that for the GPS satellites.

  • Mike Hunts
    Mike Hunts 10 months ago

    /\/ £ |2 |) $ ( |-| /-\ /\/ £ |_

  • CailloS
    CailloS 10 months ago

    NNEEEEEEERRRRRRRRRRRRDDD... jk.. but who cares? literally a really small fraction of a fraction of a second less than what he was recorded as...

  • opendebate
    opendebate 11 months ago +1

    This is what happen when a math guy trying to explain physics

  • William Regnier
    William Regnier 11 months ago

    No. He ran 9.58 seconds.

    • Starblind11
      Starblind11 10 months ago

      As was clearly stated in the video, he ran 9.63 at the London Olympics. You're referring to Berlin, which happened in a different year.

  • 911gp
    911gp 11 months ago +2

    Why so many thumbs down ?

  • raudh1
    raudh1 11 months ago


  • Barnie Smarny
    Barnie Smarny 11 months ago

    Since starting blocks were used in modern 100m races ,runners have their feet in the blocks maybe a metre or more from the line where its suitable to push off . because runners chose to use blocks they would be doing 100m's a fraction quicker too.

  • Zlatan Ibrahimovic
    Zlatan Ibrahimovic 11 months ago

    Two cars can both be going at c towards each other. The gap can close at 2c, because the gap isn't matter/energy. I assume I'm missing something?

    • Zlatan Ibrahimovic
      Zlatan Ibrahimovic 9 months ago

      Thanks for that. You're missing a reason. EDIT: I'm aware of the mistake I made, I'm just not sure you are.

    • Reg Kray
      Reg Kray 9 months ago

      you are missing a brain

  • Davis Robinson
    Davis Robinson 11 months ago

    The answer is no, he didn't, because he beat that time and ran it in 9.58

  • PhotographyJo- Taj Alami
    PhotographyJo- Taj Alami 11 months ago +1

    That's a waste of time

  • gian fernandez
    gian fernandez 11 months ago

    But me can run 1 km in 3.1415926535897932384626433832795028841971693993751058209747445923078164

  • Emrah Ekinci
    Emrah Ekinci Year ago

    Maybe the Stadium Clock DID show 9.6299...99442 but rounded up for us layman and it showed 9.63 ? You ever thought about that ? No .. you just started spewing out your theory of S.R. stuff around ! :D

  • Yanick Willert
    Yanick Willert Year ago

    or the stadium clock just rounded up...

  • West Yorkshire
    West Yorkshire Year ago

    You dont have to change what you think because majority of people agree your wrong

  • Lita León M.
    Lita León M. Year ago

    what is wrong with you people!? this is a very interesting channel that makes videos about MATHEMATICS, not clickbaits like the ones all of you are used to. RESPECT!!

  • nisse26a
    nisse26a Year ago

    naught naught naught naughty

  • jim jimjim
    jim jimjim Year ago

    Where is your chin?

  • M Lion
    M Lion Year ago

    This guy is the exact type of guy who would argue with the cashier at McDonald for giving him 1 less fry than the average amount.

  • SuperMarioMemes
    SuperMarioMemes Year ago

    First we care about about some laundry square, now we care about 0.000000000005 seconds? What next, the colour of someone’s eyes?

  • cormac king
    cormac king Year ago

    What about his 9.58?

  • Manny Mandem
    Manny Mandem Year ago

    I like this guy

  • Bulletless
    Bulletless Year ago

    I want to die now who can be so sad to acc do this

  • #IHateRappers #ProudCatOwner #IEatPussy

    Wait but for track i did a 100m and finished in 11 seconds, theres no way usian bolts only 2 seconds faster than me.

  • Patrick DeStefano

    It was actually 9.58

  • ram suresh
    ram suresh Year ago

    Wtf Mr.Einstein ...why did you make life so hard and complicated for many of us students ??

  • Ewan Green
    Ewan Green Year ago


  • Bargain Bin Gaming

    Police are milliseconds away when nanoseconds matter.

  • FrenzzyLeggs2006
    FrenzzyLeggs2006 Year ago

    What do I do with this knowledge

  • Zsamalao
    Zsamalao Year ago +1

    He ran it in 9.58

  • Srivatsa Bolisetti

    give me a like

  • Thiccest Chungus
    Thiccest Chungus Year ago

    why am i watching this im like 6 years old

  • Jason Li
    Jason Li Year ago

    What the hell’s an American billion? I know they don’t use the metric system, but I didn’t know they had different numbers.

    • Reg Kray
      Reg Kray 9 months ago

      Well you know now

  • Kauan R. M. Klein

    If he'd run 10 seconds at the speed of light (according to the stadium's clock), how much time passed would his clock display?

    • Reg Kray
      Reg Kray 9 months ago

      no time would have passed

  • Egil Sandnes
    Egil Sandnes Year ago

    Naughty number at 1.57

  • David KP
    David KP Year ago +1


  • Mr.Butler
    Mr.Butler Year ago

    Why would this be relevant

  • Honza Halek
    Honza Halek Year ago

    no, if he had a watch, it would not show that time you said because the stadium clock is not even slightly this accurate and even if it was, the time 9:63 is obviously rounded very much so the very little difference that special relativity makes does not affect what is or would be on the clock.

  • Max Kobzar
    Max Kobzar Year ago

    I'm 100% sure that he's a virgin

  • Talha ŞAHİN
    Talha ŞAHİN Year ago


  • RabidChimpmunk
    RabidChimpmunk Year ago

    What kind of watch you got that reads that far boi

  • TalMojo
    TalMojo Year ago

    Despite if this is true, your telling me that the resolution of his clock was a billionth of a second, uhhh I don't think so.

  • Kyle Merson
    Kyle Merson Year ago

    Respect bro

  • Magic Rojava
    Magic Rojava Year ago

    Here we go... a cheater.

  • Chillvgaming
    Chillvgaming Year ago

    Its just the click their is adding it up to 9:63 bevares it ddosent matter

  • Dehan Badenhorst
    Dehan Badenhorst Year ago

    The 8k dislikes are unintelligent beings.

  • its_n
    its_n Year ago

    I’m slow asf and run mine in 15 seconds 😂

  • James Green
    James Green Year ago

    Well they round it