"Martin Baxter" wrote in message
...
Martin Baxter wrote:
Martin Baxter wrote:
Gordon wrote:
This is from the Brian Toss rigging book so if you want to cheat, you
can look it up.

If I string a line around the equator (disregarding natural
obstacles) and then decide I want that line 1 foot above the equator
all the way around, how much longer must that line be? Call the earth's
diameter an even 8000 miles.
G


circumference = pi*d

so difference = (pi*(8000+(1/5280))-(pi*8000)miles

=pi/5280 miles

multiply by 5280'/mile and you get pi ft. (3.2459')

do a little simple algebra


all you have to do is expand the first term:

pi*8000 + pi/5280, subtract the second term and you are left with pi/5280

Or, intuitively, since circumference is diameter time pi, to make the
circumference grow by one foot, you must add pi feet to the diameter;
doesn't matter if the diameter is 1 foot or a light-year, you still add
pi feet.

Ooops, just noticed I only increased the elevation by 6", so change that
to 2pi feet. same principle.



Cheers
Martin

Pie feet? Is that what you get from stomping fruit to make filling?
Maybe why we never hear of "grape pie"?