Search results
Results from the WOW.Com Content Network
The trace (purple) of the tangents of a conical spiral with a hyperbolic spiral as floor plan. The black line is the asymptote of the hyperbolic spiral. The collection of intersection points of the tangents of a conical spiral with the --plane (plane through the cone's apex) is called its tangent trace.
Any cylindrical map projection can be used as the basis for a spherical spiral: draw a straight line on the map and find its inverse projection on the sphere, a kind of spherical curve. One of the most basic families of spherical spirals is the Clelia curves , which project to straight lines on an equirectangular projection .
In cylindrical coordinates, the conchospiral is described by the parametric equations: = = =. The projection of a conchospiral on the (,) plane is a logarithmic spiral.The parameter controls the opening angle of the projected spiral, while the parameter controls the slope of the cone on which the curve lies.
Examples include the plane, the lateral surface of a cylinder or cone, a conical surface with elliptical directrix, the right conoid, the helicoid, and the tangent developable of a smooth curve in space. A ruled surface can be described as the set of points swept by a moving straight line.
A curve is called a general helix or cylindrical helix [4] if its tangent makes a constant angle with a fixed line in space. A curve is a general helix if and only if the ratio of curvature to torsion is constant. [5] A curve is called a slant helix if its principal normal makes a constant angle with a fixed line in space. [6]
Its name derives from its similarity to the helix: for every point on the helicoid, there is a helix contained in the helicoid which passes through that point. The helicoid is also a ruled surface (and a right conoid), meaning that it is a trace of a line. Alternatively, for any point on the surface, there is a line on the surface passing ...
Wallis's conical edge is also a kind of right conoid. It is named after the English mathematician John Wallis, who was one of the first to use Cartesian methods to study conic sections. [1] Figure 2. Wallis's Conical Edge with a = 1.01, b = c = 1 Figure 1. Wallis's Conical Edge with a = b = c = 1
Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Donate