Everything Totally Explained


Ask & we'll explain, totally!
Evolute
Totally Explained


  NEW! All the latest news in the worlds of computer gaming, entertainment, the environment,  
finance, health, politics, science, stocks & shares, technology and much, much, more.  


View this entry using RSS

Everything about Evolute totally explained

In the differential geometry of curves, the evolute of a curve is the locus of all its centers of curvature. Equivalently, it's the envelope of the normals to a curve. The original curve is an involute of its evolute. (Compare and )

History

Apollonius (c. 200 BC) discussed evolutes in Book V of his Conics. However, Huygens is sometimes credited with being the first to study them (1673).

Equations

Let (x, y) = (x(t), y(t)) be a parametrically defined plane curve. Let R = 1/kappa be the radius of curvature and phi be the tangential angle. Then the center of curvature at (x, y) is given by (x - R sin phi, y + R cos phi) and we may take (X, Y) = (x - R sin phi, y + R cos phi) as parametric equations for the evolute. We have (cos phi, sin phi) = frac)

Examples

  • The evolute of a parabola is a semicubical parabola. The cusp of the latter curve is the center of curvature of the parabola at its vertex.
  • The evolute of a Logarithmic spiral is a congruent spiral.
  • The evolute of a cycloid is a similar cycloid.Further Information

    Get more info on 'Evolute'.


    External Link Exchanges

    Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:

      <a href="http://evolute.totallyexplained.com">Evolute Totally Explained</a>

    Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
       As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned.



  • Copyright © 2007-8 totallyexplained.com | Licensed under the GNU Free Documentation License | Site Map
    This article contains text from the Wikipedia article Evolute (History) and is released under the GFDL | RSS Version