Home News Entertainment Sport Business Weather Video Reports Quiz | ||||
Going Out TV Guide Site Directory Alerts Web Search About Ananova | ||||
|
|
|
Mathematicians in Pennsylvania are using a robot arm and a bath plug chain to help magicians master a conjuring trick. They're trying to improve the odds of flicking a rope and successfully making a knot in it. Experts say a rope only knots itself within a certain range of shaking motions - shake it too little or too much and no knot will form. Even in the given range, self-knotting then depends on collisions between different parts of the chain. Andrew Belmonte of the Pennsylvania State University team attached one end of a chain to an arm which vibrated up and down. At very low frequencies the hanging chain moves up and down but later it starts to swing. Later still, the motion becomes chaotic and with even more vigorous shaking it finally starts to rotate and swing around the arm. Experiments show knots only appear when the motion is in its chaotic phase and when the free end of the chain passes through temporary loops. The study is published in Physical Review Letters and reported in the journal Nature. Story filed: 10:32 Tuesday 11th September 2001 RELATED STORIES:
|
Home - News - Entertainment - Sport - Business - Weather - Video Reports - Going Out - TV Guide - Site Directory - Alerts - Quiz - About Ananova - Contact Ananova |
Copyright © 2001 Ananova Ltd Terms and conditions of use - Privacy policy - Corrections |