Cone

A cone is a basic shape in geometry. Several things have also been called cones on account of their shape:

A volcanic cone is a mountain formed by material ejected from a volcanic vent.
In relativity, the light cone of an event consists of all spacetime events that can interact with it.
The scaly fruit-like reproductive bodies of certain plants, especially conifers (Pinophyta) and cycads (Cycadophyta), are called cones: see conifer cones, and Pinophyta.
In vertebrate anatomy, a cone cell is a type of light-sensitive cell found along with rods in the retina of the eye.
In ceramics manufacture, a cone is a conical or pyramidal mineral stick that is used to gauge the temperature of an oven.
An ice cream cone is a container for ice cream, shaped like an inverted cone open at its top. It is often made of edible pastry.
A traffic cone is a brightly colored cone-shaped plastic object commonly used as a temporary traffic barrier or warning sign.
In basketball, a cone is a player who is so slow and unskilled, that you can dribble around them as if they were a traffic cone.

The word cone and its derivatives also have several specialized meanings in mathematics:

In geometry, cone is often used informally for conical surface, usually a right circular one; see cone (geometry).
Also in geometry, the cone of an arbitrary set <math>X<math> means the union of all line segments connecting a fixed point to points of <math>X<math>. For exmple, this coning operation will turn a triangle into a tetrahedron.
In topology, too, coning may be applied to a topological space, e.g. to define the barycentric subdivision of a cell complex; see cone (topology).
In linear algebra, the convex cone of a set of vectors consists of all linear combinations of those vectors with non-negative coefficients.
In descriptive geometry, "conical projection" is another name for the perspective projection.
In cartography, however, a conical projection maps the spherical surface of the Earth to a conical surface, that is then unrolled onto a plane.
A conic section is any curve obtained by cutting the surface of a cone (more precisely, a conical surface) by an arbitrary plane.

This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. If an article link referred you here, you might want to go back and fix it to point directly to the intended page.

ca:Con de:Kegel es:Cono fr:C�ne ja:円錐 pl:Stożek

Retrieved from "http://www.mywiseowl.com/articles/Cone"

This page has been accessed 634 times. This page was last modified 03:26, 9 Nov 2004. All text is available under the terms of the GNU Free Documentation License (see Copyrights for details).