Date: Mon, 2 Aug 1993 21:29:15 -1000
From: salanne@convex.csc.FI (Simo Salanne)
Message-Id: <1993Aug3.072915.29264@nic.funet.fi>
Organization: Finnish Academic and Research Network Project - FUNET
Subject: Re: Size of soccer ball (Was: Single Line Report)
In <1993Aug2.230423.24984@amc.com> marty@amc.com (Marty Akerman) writes:
>And in regards to the soccer ball, Jeff also says:
>>What formula are you using to figure out what size template will produce
>>a certain size of ball?
>Well, my 3" faces made a ball about 14" in diameter, so the ratio 14/3 is
>what I use to determine resulting ball size from face size. Andrew Beattie
>mentions that he uses a ratio of 5, which is pretty close too. I'm not
>enough of a math wizard to figure out precisely what the ratio is, so 5 works
>good enough for back of a napkin types of estimating.
Well, I did some morning exercise and suggest that, if the lenght of
the pentagon/hexagon edge is L, then the diameter of the ball will be
approximately:
D = 4.2 * sqrt(L)
I calculated the total area of 19+1 hexagons and 12 pentagons,
and derived the diameter from the area of a ball.
Smooth Winds
Simo.Salanne@csc.fi
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Date: Tue, 3 Aug 1993 01:35:28 -1000
From: salanne@convex.csc.FI (Simo Salanne)
Message-Id: <1993Aug3.113528.24872@nic.funet.fi>
Organization: Finnish Academic and Research Network Project - FUNET
Subject: Re: Size of soccer ball (Was: Single Line Report)
In <1993Aug3.072915.29264@nic.funet.fi> salanne@convex.csc.FI (Simo Salanne) writes:
>Well, I did some morning exercise and suggest that, if the lenght of
>the pentagon/hexagon edge is L, then the diameter of the ball will be
>approximately:
> D = 4.2 * sqrt(L)
>I calculated the total area of 19+1 hexagons and 12 pentagons,
>and derived the diameter from the area of a ball.
Should have waited until awake. Let's forget sqrt and say simply:
D = 4.2 * L
Simo