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Posers and Puzzles

Posers and Puzzles

  1. Donation Acolyte
    Now With Added BA
    30 Sep '02 23:15
    In this problem you have a special watch that tells you exactly what local time is, with 12:00
    always being the time when the Sun is highest in the sky at that point (ie no Daylight Saving
    Time and no irregular Time Zones.)

    When you leave your house, your watch says 06:00.

    You turn to face east and travel in a straight line.

    When you stop, your watch says 18:00 and you have reached a longitude of 60°E.

    You now turn to face west and travel in another straight line for the same distance as before.

    When you stop this time, your watch still says 18:00.

    You now travel due south until you get home, by which time your watch says 22:00.

    You travel at a constant speed the whole time, and get back on the same day as you left.
    Where do you live?
  2. Donation richjohnson
    01 Oct '02 01:48
    How do you travel in a straight line on the surface of a sphere (or are
    you travelling in a plane or spaceship)?
  3. 01 Oct '02 03:27

    From now on, consider every instance of the phrase "straight line"
    used in reference to travel on the surface of the earth duly modified to
    mean "the shortest path from A to B following the appropriate great
    circle of the earth." Shall we also allow for the earth's equatorial bulge
    in our calculations?

    --Rein, who needs a little nappy-poo now
  4. Donation Acolyte
    Now With Added BA
    01 Oct '02 09:08
    OK, so we can agree on a few things for the purposes of these Earth puzzles:

    No tunneling through the Earth, no wormholes, no teleportation devices.
    All speeds and distances are relative to the surface of the Earth.

    Newtonian physics applies (except that any movement of the traveller has no effect on the
    movement of the Earth.)
    The Earth is a perfect sphere.

    And finally, the answer should always use either nice round numbers or simple fractions.
  5. 01 Oct '02 21:29
    Oh, and also, that I am always right.

    --Rein, who is always right.
  6. 02 Oct '02 20:53
    Is that: "Right as Rein"?

  7. 03 Oct '02 19:15
    You know, I like that.

  8. Donation Acolyte
    Now With Added BA
    12 Oct '02 07:29