# Did Usain Bolt REALLY run 100m in 9.63 seconds?

Share
Embed
• 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?
More links & stuff in full description below ↓↓↓
NUMBERPHILE
Website: www.numberphile.com/
Subscribe: bit.ly/Numberphile_Sub
Patreon: www.patreon.com/numberphile
Numberphile T-Shirts: teespring.com/stores/numberphile
Other merchandise: store.dftba.com/collections/numberphile
• Science & Technology

• Ambassador Kees 2 days ago

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

• 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 5 days ago

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

• 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 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 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 29 days ago +1

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

• nowonmetube Month ago

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

• Louis Rouxel Month ago

No since he ran it in 9.58 seconds.

• 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 2 months ago

click bait

• GoldyLuck 2 months ago

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

• Sayon 2903 3 months ago

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

• 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 3 months ago

This video is a big waste of time

• Greg 4 months ago

This is so ridiculous

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

• J W 4 months ago +1

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

• 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 4 months ago +1

+Tim Cuffman opps no i meant his result

• 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 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 5 months ago

Yawnphile.

• 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...

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 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

• Scott Anderson 6 months ago

Gorillas run the 100 in nine flat

• Me Playzz 6 months ago

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

• 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 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 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 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 7 months ago

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

• Atraya Bajpai 7 months ago +1

9.58

• Justin T 7 months ago

Got to go fast to stay young

• Przemyslaw Sliwinski 7 months ago

What if we put a stadium clock a little higher?

• Hiba Zreik 7 months ago

Physicsphile

• Yoda Yoda 7 months ago

When you’re that bored...

• 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 8 months ago

4:25

• 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 8 months ago

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

• Alex Rodriguez 8 months ago

• bhrugu rajput 8 months ago

2:20 Jake Peralta ??

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

• Sam Nasam 8 months ago

did he really run 100m?

• Brad King 9 months ago

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

• 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 9 months ago

Nah he jogged it

• Fraud Samaritan 9 months ago

what do you mean track shrank?

• Venkatesh babu 9 months ago

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

• BillNGX 10 months ago

Surely his watch would tell the time?

• Paul George 10 months ago

Nah he ran 9.58

• James Latimer 10 months ago

He wears a cheap Rolex made in Japan

• 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 10 months ago

/\/ £ |2 |) \$ ( |-| /-\ /\/ £ |_

• 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 11 months ago +1

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

• William Regnier 11 months ago

No. He ran 9.58 seconds.

• 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 11 months ago +2

Why so many thumbs down ?

• raudh1 11 months ago

Yes

• 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 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 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 9 months ago

you are missing a brain

• 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 11 months ago +1

That's a waste of time

• gian fernandez 11 months ago

But me can run 1 km in 3.1415926535897932384626433832795028841971693993751058209747445923078164

• 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 Year ago

or the stadium clock just rounded up...

• West Yorkshire Year ago

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

• 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 Year ago

naught naught naught naughty

• jim jimjim Year ago

• 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 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 Year ago

• Manny Mandem Year ago

I like this guy

• Bulletless Year ago

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

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

• It was actually 9.58

• ram suresh Year ago

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

• Ewan Green Year ago

2018?

• Police are milliseconds away when nanoseconds matter.

• FrenzzyLeggs2006 Year ago

What do I do with this knowledge

• Zsamalao Year ago +1

He ran it in 9.58

• give me a like

• Thiccest Chungus Year ago

why am i watching this im like 6 years old

• 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 9 months ago

Well you know now

• 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 9 months ago

no time would have passed

• Egil Sandnes Year ago

Naughty number at 1.57

• David KP Year ago +1

9.58*

• Mr.Butler Year ago

Why would this be relevant

• 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 Year ago

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

• Talha ŞAHİN Year ago

WE UNDERSTOOD BOLT IN USA IS FASTER THAN USAIN BOLT

• RabidChimpmunk Year ago

What kind of watch you got that reads that far boi

• 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 Year ago

Respect bro

• Magic Rojava Year ago

Here we go... a cheater.

• Chillvgaming Year ago

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