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Re: Displacement



At 07:27 AM 10/9/01 -0500, Pete Lohstreter wrote:
Suppose you exercise by walking for 15 minutes on a treadmill that has a
level track that moves at a velocity of -4km/hr.
...
Displacement = 0 km
Distance = 1 km

Yuck!

The displacement is 0km in one frame and 1km in another plausible &
sensible frame. It's really bad practice to assert "my frame is right and
your frame is wrong".

The rules are:
-- Choose whatever frame you like.
-- If you need to communicate a frame-dependent result, clearly state
what frame you've chosen.
-- Be tolerant of those who choose a different frame.

Also: In any particular frame, for unaccelerated motion, I would have expected
distance = |displacement|
But alas the alleged numbers above are not consistent with this.