On 08/13/2014 9:33 AM, rangerssuck wrote:
On Wednesday, August 13, 2014 6:43:55 AM UTC-4, Doug Miller wrote:
...
Related thought experiment: suppose you have a string wrapped
tightly around the surface of the earth. How much longer does that
string need to be, if you want to put it on one-foot-high
standoffs all around the planet?
...
About 8" (two feet / pi).
....

C2=pi*D2; C1=pi*D1 -- C2-C1=pi*(D2-D1) = 2*pi ft

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