Re: spherical geometry (was Re: navigation riddle)

[Jack Uretsky <jlu@HEP.ANL.GOV>]

On Sat, 14 Aug 2004, David Bowman wrote:

> Regarding Jack's comments:
>
> > I think that the interesting part of the original problem is that it
> > requires the solver to realize that plane geometry is not involved.
>
> I disagree.  The radius of curvature of the earth is over 6000 times
> the length scale of the problem as it is stated.  A flat earth
> approximation is quite sufficient.
______________________________________snip_______________________
> David Bowman

        It all depends on what one means by "going east".  If you're a
flat earther on an Iowa prairie, the directions given will take you along
the sides of an equilateral triangle - unless you just came out of Ms.
Dorkey's geometry class and want to try your hand at polar coordinates.
If you already know the answer and want to justify it, then David's
argument fits perfectly, except it doesn't let you have a second solution
because a flat earth can only have one pole.


--
"Trust me.  I have a lot of experience at this."
                General Custer's unremembered message to his men,
                just before leading them into the Little Big Horn Valley



                                                Regards,
                                                        Jack