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Re: navigation riddle

Whoops, I meant 'inclination' and not 'declination'.

How do you get back to point A from any of Herb's infinite number of points
by travelling anything other than eastward or westward for a mile? And would
Bruce describe one of his points that fitsthe requirement?

If you started a mile from the south pole and walked a mile south, there
would be no such thing as east when you arrived.

Yours sincerely
Craig Lucanus
----- Original Message -----
From: "Herb Schulz" <herbs@WIDEOPENWEST.COM>
To: <PHYS-L@LISTS.NAU.EDU>
Sent: Thursday, August 12, 2004 9:04 PM
Subject: Re: navigation riddle


On 8/12/04 6:03 AM, "John Denker" <jsd@AV8N.COM> wrote:

Since phys-l has been somewhat listless lately, here
is a riddle:

Dr. Livingstone starts out at a place which we call
Point A. He then undertakes a journey consisting
of three legs:
-- he travels precisely southward for one mile;
-- then he turns and travels precisely eastward
for one mile;
-- then he turns and travels precisely northward
for one mile.
He discovers that as a result of this journey, he
has returned to Point A.

Note: He travels by airship, at an appropriate constant
altitude, so you don't need to worry about obstructions
or other nonidealities.

The questions are:

1) Where is Point A?
2) Are you sure? How do you know?

===========

Usual ground-rules: The right answer depends on
understanding the physics of the situation. This may
require some outside-the-box thinking. Everything
I've said is intended to be true and helpful. I expect
a strong consensus as to the correctness of the answer.


Howdy,

Besides the North Pole there are an infinite number of points along a
Latitude that is 1 mile North of the Latitude whose circumference is 1
mile,
or 1/2 mile, or ... 1/n mile (n = non-zero positive integer).

Good Luck,

Herb Schulz
(herbs@wideopenwest.com)