How colliding blocks act like a beam of light...to compute pi.

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3Blue1Brown

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Shared February 3, 2019

The third and final part of the block collision sequence.
Part 1: https://youtu.be/HEfHFsfGXjs
Part 2: https://youtu.be/jsYwFizhncE
Home page: https://www.3blue1brown.com
Brought to you by you: http://3b1b.co/clacks-thanks

Error correction: I wrote the answer as floor(pi/theta), when really it should be ceiling(pi/theta) - 1 t account for values of theta perfectly dividing pi. For example, the case of equal masses gives an angle of pi/4, and 3 total clacks.

This beautiful result, and the solution shown here, are due to Gregory Galperin:
https://www.maths.tcd.ie/~lebed/Galpe...

And here's a lovely interactive built by GitHub user prajwalsouza after watching this video: https://prajwalsouza.github.io/Experi...

Speaking of looking glass universes...
https://www.youtube.com/user/LookingG...

NY Times blog post about this problem:
https://wordplay.blogs.nytimes.com/20...

The plushie pi shown at the video's start:
https://www.3blue1brown.com/store

If you want to contribute translated subtitles or to help review those that have already been made by others and need approval, you can click the gear icon in the video and go to subtitles/cc, then "add subtitles/cc". I really appreciate those who do this, as it helps make the lessons accessible to more people.

Music by Vincent Rubinetti.
Download the music on Bandcamp:
https://vincerubinetti.bandcamp.com/a...

Stream the music on Spotify:
https://open.spotify.com/album/1dVyjw...

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3blue1brown is a channel about animating math, in all senses of the word animate. And you know the drill with YouTube, if you want to stay posted on new videos, subscribe: http://3b1b.co/subscribe

Various social media stuffs:
Website: https://www.3blue1brown.com
Twitter: https://twitter.com/3blue1brown
Reddit: https://www.reddit.com/r/3blue1brown
Instagram: https://www.instagram.com/3blue1brown...
Patreon: https://patreon.com/3blue1brown
Facebook: https://www.facebook.com/3blue1brown



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