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

Home > Shapes > Geometry
Conic Spiral (Posted on 2009-08-06) Difficulty: 3 of 5
A string is wound around a cone with base radius 1 cm and slant height 10 cm. The string is wrapped in a helical manner, as if a strand of lights decorating a Christmas tree, except that it is pulled taut around the cone so as to have no local "wiggles", thus making what is known mathematically as a geodesic curve on the surface of the cone.

What is the maximum length of such a spiral around the cone before it starts to intersect itself?

  Submitted by Jer    
No Rating
Solution: (Hide)
10/cos(18) or about 10.5146 cm.

In general the maximum length is the slant height divided by the cosine of half the vertex angle formed by the net of the cone.

Comments: ( You must be logged in to post comments.)
  Subject Author Date
re: computer solutionHarry2009-08-06 21:07:15
Solutioncomputer solutionCharlie2009-08-06 17:38:33
Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (13)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2024 by Animus Pactum Consulting. All rights reserved. Privacy Information