Talk:Truncated icosahedron
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Why does the soccer ball must have 32 faces? Why not 36 or 40 or any number of face?
- Because the rulebook states that a soccerball must be a truncated icosahedron. All sports have arbitrary rules such as the 18 holes on golf as oppsed to 22 or some other number.
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- Ŭalabio 05:24, 2004 Dec 30 (UTC)
I tried playing around with layout--in IE on my screen there are weird white spaces that I can't seem to correct. (The white spaces were there even before I edited it.) It looks OK in Opera, but even there the football pic winds up all alone under the table. 4.236.78.198 17:32, 21 October 2005 (UTC)
[edit] What does the Truncated part mean?
Is there an article on the naming nomenclature of plyhedra or Archimedean solids or whatever? Dalf | Talk 06:45, 2 February 2006 (UTC)
Meaning of the names certainly could/should be described in Archimedean solid. Truncated means you take a polyhedron and slice off the corners, cutting original edges into 1/3rds, so middle third of original edges remain and original faces get doubled - triangles into hexagons in this case. Tom Ruen 07:03, 2 February 2006 (UTC)
- Yea I figured it was the corners after looking at a catagory and opening 8 articles that were truncated polyhedra of some sort. Looks like about 80% of the articles link to truncated or truncate which is a read link. I think [[Truncation (geometry) might be a better name though as there is no article at any of the location I suppose Tuncation would be as good a place as any. The 1/3 thing and other details should be explained somehwere, and if it does not deserv its own article one or emore of the above articles shludl be redirected to whereever it is explained. Dalf | Talk 08:28, 2 February 2006 (UTC)
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- There's ennumerable improvements like this, and you have no disagreement from me, just time. Probably polyhedron is the best place to describe terminology. Tom Ruen 08:38, 2 February 2006 (UTC)
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- Truncation (geometry) article added now. Tom Ruen 00:57, 26 April 2006 (UTC)
Ok I need to add that there's a formula that follows 10E8 which shows that if a fullerene is to the soccer ball as the soccer ball is to the earth.. someone please articulate this and add it thanks!
[edit] Dome construction using Truncated Icosahedron
Given the diameter of a Truncated Icosahedron sphere, how to figure out the side length of associated hexagons and pentagons?--Jdpan 19:39, 14 February 2007 (UTC)
- According to an old book I have here, the ratio of the length of an edge of a truncated icosahedron to the radius of a CIRCUMSCRIBED sphere is 2*sin(theta/2), where theta is the angle subtended by an edge (in this case, about 23° 17'), or about 0.4036. For an inscribed or "interscribed" sphere, the results would be different... 19:54, 14 February 2007 (UTC)
P.S. You could get the same result from the data provided in the article, that the radius of the circumscribed sphere is sqrt(9φ + 10) (where "φ"=φ = (1+√5)/2) when the edges have length 2. My calculator gives 0.40354821233519770308113433897167 as the ratio... AnonMoos 12:16, 15 February 2007 (UTC)
[edit] A popular culture reference
I think that the "tritium" (or its container) in Spider Man 2 had the shape of a truncated icosahedron... --Itub 15:16, 13 March 2007 (UTC)
