Right Conoid
A Ruled Surface is called a right conoid if it can be generated by moving a straight Line intersecting afixed straight Line such that the Lines are always Perpendicular (Kreyszig 1991, p. 87). Taking the Perpendicular plane as the 
-plane and the line to be the x-Axis gives the parametricequations
 |  |  | |
 | |  | |
 | |  |
(Gray 1993). Taking
and 
gives the Helicoid.See also Helicoid, Plücker's Conoid, Wallis's Conical Edge
References
Dixon, R. Mathographics. New York: Dover, p. 20, 1991. Gray, A. Modern Differential Geometry of Curves and Surfaces. Boca Raton, FL: CRC Press, pp. 351-352, 1993. Kreyszig, E. Differential Geometry. New York: Dover, 1991.
- Cartesian Trident
- Cartography
- Cascade
- Casey's Theorem
- Casimir Operator
- Cassini Ellipses
- Cassini Ovals
- Cassini Projection
- Cassini's Identity
- Cassini Surface
- Castillon's Problem
- Casting Out Nines
- Catacaustic
- Catalan Integrals
- Catalan Number
- Catalan's Conjecture
- Catalan's Constant
- Catalan's Diophantine Problem
- Catalan Solid
- Catalan's Problem
- Catalan's Surface
- Catalan's Triangle
- Catalan's Trisectrix
- Catastrophe
- Catastrophe Theory