All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Science
Come Sail Away (Posted on 2007-02-12) Difficulty: 3 of 5
A sailboat race is held on a river that runs directly North to South, with a current of 12 knots. A 25 mile race is held going downriver (south). The first heat is held early in the day when there is no wind. The second heat, also going downriver, is held later, when there is a 12 knot tailwind (from the North). In which heat are the fastest times recorded?

See The Solution Submitted by Kenny M    
Rating: 3.0000 (2 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
re(2): solution | Comment 5 of 9 |
(In reply to re: solution by Joel)

I also find tacking counterintuitive. But in still water, with the wind coming directly from the south, it is possible to proceed southward on a zigzag path by tacking. The first heat represents this condition, though it happens that the dry land is, relatively speaking, going northward along with the wind, so the relative speed of the boat vis-a-vis the land is the 12 knots the land is travelling plus whatever counterintuitive progress the boat is making in the water.  In the second heat the relative motion of the boat to the land is only the 12 knots.
  Posted by Charlie on 2007-02-14 10:06:57

Please log in:
Remember me:
Sign up! | Forgot password

Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (3)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Copyright © 2002 - 2018 by Animus Pactum Consulting. All rights reserved. Privacy Information