On Wed, 13 Aug 2014 07:54:08 -0700 (PDT), rangerssuck
wrote:

On Wednesday, August 13, 2014 10:44:45 AM UTC-4, Ed Huntress wrote:
On Wed, 13 Aug 2014 07:33:46 -0700 (PDT), 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).



Uh, that's two feet *times* pi. g

yeah, well, haven't finished the morning coffee yet. Besides, by the time they finished building all those little standoffs, I'd have been paid and spent the money. So sue me ;-) And it's all a trick question anyway: EVERYONE knows the earth is flat.

Don't forget that the string will stretch. And there is the catenary
curve droop of the string *between* the standoffs. Those two factors
work against each other.

Are we having fun yet? d8-)

--
Ed Huntress



Related thought experiment: Suppose you have a mile of railroad track. Suppose it gets really hot and the track expands (in length) by one inch. Suppose that, due to the expansion, the track buckles in the middle, forming an isosceles triangle. How high will the bump in the middle be?