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Path: utzoo!dciem!tim
From: tim@dciem.UUCP (Tim Pointing)
Newsgroups: net.physics
Subject: a sailing problem
Message-ID: <235@dciem.UUCP>
Date: Tue, 7-Jun-83 08:18:04 EDT
Article-I.D.: dciem.235
Posted: Tue Jun  7 08:18:04 1983
Date-Received: Tue, 7-Jun-83 08:33:33 EDT
Lines: 18

This is a problem that my father, a University prof, has posed to
his students for some years and I thought it would be appropriate
to sollicit responses from this group. The problem is this: a sailboat is
drifting down the Amazon at the speed of the current (say 2mph). The    
captain observes smoke from fires on the shore rising vertically (i.e. it
is a dead calm). Feeling a slight headwind (because the boat is drifting 
with the water), he orders the crew to raise the sail so that they
can make better time by tacking into the wind. The crew, feeling rather
bright, tells the captain that raising the sail will slow the boat down
because of the drag.

Q: Who is right, the captain or the crew (and why)?

Submit answers and I will post a summary.


                                        Tim Pointing
                                ...!decvax!utzoo!dciem!tim