Generatrix

In geometry, a generatrix (/ɛnəˈrtrɪks/) or describent is a point, curve or surface that, when moved along a given path, generates a new shape.[1] The path directing the motion of the generatrix motion is called a directrix or dirigent.[2]

Examples

A cone can be generated by moving a line (the generatrix) fixed at the future apex of the cone along a closed curve (the directrix); if that directrix is a circle perpendicular to the line connecting its center to the apex, the motion is rotation around a fixed axis and the resulting shape is a circular cone.[3]

The generatrix of a cylinder, a limiting case of a cone, is a line that is kept parallel to some axis.

See also

References

  1. "generatrix". merriam-webster.com. Retrieved 11 September 2014.
  2. "generatrix". mathopenref.com. Retrieved 11 September 2014.
  3. "Cone". britannica.com. Retrieved 11 September 2014.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.