Bryan wrote:
"Armond Perretta" wrote ...
Bryan wrote:
"Dave" wrote ...
"Bryan" said:

If a sailboat leaves Miami at 5 knots per hour, how fast will it
be going when it reaches Panama?

Impossible to determine without knowing its starting speed.

Starting speed: 0 Knots.

Can you give an instance when this is _not_ the case? Every time
I've started a trip I've experienced a starting speed of roughly
zero knots. give
or take.

Let's see. Tied up at the slip with a current running bow to stern
and the knot meter reads something above zero knots. Does that count?

No. Velocity is measured relative to the coordinate frame affixed to the
terrestrial sphere.

Consider for example a coordinate frame affixed to the vessel. In such a
case the GPS will, regardless of the physical location of the vessel, always
indicate a position where the Greenwich Meridian crosses the Equator.

--
Good luck and good sailing.
s/v Kerry Deare of Barnegat
http://home.comcast.net/~kerrydeare