
Usain Bolt’s Split Times and the Power of Calculus - furcyd
https://www.quantamagazine.org/infinite-powers-usain-bolt-and-the-art-of-calculus-20190403/
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anonu
Haven't read this article yet - but I studied the picture at the top of the
link carefully.

Not only was Bolt a mile ahead of his competitors and not only did he turn to
face the crowd as he was crossing the finish line... Usain Bolt's shoelace was
untied...

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praneshp
Haha, the article calls it out as well

"Even with his celebration (and an untied shoelace) he set a new world record
of 9.69 seconds."

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gauravjain13
The wiggles are interesting. But they also open up a can of worms - how
precise is the measuring instrument, and which part of Bolt is it measuring?
His feet, knees, torso, forehead? In engineering parlance, what’s the
metrology design? Think of UB as a noodle with each part having different
instantaneous velocities.

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thangalin
Numberphile created an entertaining video regarding Bolt's speed, the speed of
light, and the distance he actually covered while sprinting.

[https://www.youtube.com/watch?v=tflf05x-WVI](https://www.youtube.com/watch?v=tflf05x-WVI)

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melling
Seems to be promoting a new book that was released yesterday:

[https://www.amazon.com/Infinite-Powers-Calculus-Reveals-
Univ...](https://www.amazon.com/Infinite-Powers-Calculus-Reveals-
Universe/dp/1328879984/)

~~~
sohkamyung
The subheading does say this:

 _This adapted book excerpt from Infinite Powers ..._

So it might not be correct to say the article is promoting the book, rather,
the article is adapted from parts of the book.

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nyc111
If I'm not mistaken, interpolation methods existed before the invention of
calculus. Interpolation was used to reduce astronomical data before calculus,
afaik.

Would it be possible to find the speed on any given moment without calculus?
Is it just easier with calculus?

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gorb314
This article brings to my mind the joke about the physicist and spherical
chickens in a vacuum.

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bigiain
"Assume a perfectly spherical cow of uniform density"...

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z3t4
The 100m dash have three phases, acceleration, top speed, and speed endurance.
Almost all sprinters deaccelerate at the last 20m. Bolt had very good speed
endurance, probably because his 200m training.

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gauravjain13
Source? And why would they decelerate? Extrapolating from your last sentence –
fatigue? Would be interesting to compare acceleration at 80m in a 100m sprint
vs. a 200m sprint.

~~~
drdrey
The energy system that is used for explosive power can only last a few
seconds, after that muscles have to use another energy source

[https://en.wikipedia.org/wiki/Bioenergetic_systems#ATP-
CP:_T...](https://en.wikipedia.org/wiki/Bioenergetic_systems#ATP-
CP:_The_phosphagen_system)

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Ancalagon
Probably just the topics of the article, but I think this is the first of the
recent glut of fluff pieces that I enjoyed almost every bit of.

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tacon
I was rather disappointed in this article, since it was making the connection
to calculus. Where is the curve of acceleration? Where is the curve for jerk?
Where is the calculation for maximum force on his body from that acceleration?

[https://en.wikipedia.org/wiki/Jerk_(physics)](https://en.wikipedia.org/wiki/Jerk_\(physics\))

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hopler
You are disappointed at the article for not being a different article?
Velocity is the derivative of position

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tacon
Yes, I am disappointed that an article with "power of calculus" in the title
left most of the power of calculus out of the article.

>Velocity is the derivative of position

Thanks, hadn't noticed that.

