tangency
31Villarceau circles — In geometry, Villarceau circles (pronEng|viːlɑrˈsoʊ) are a pair of circles produced by cutting a torus diagonally through the center at the correct angle. Given an arbitrary point on a torus, four circles can be drawn through it. One is in the… …
32Nose cone design — Given the problem of the aerodynamic design of the nose cone section of any vehicle or body meant to travel through a compressible fluid medium (such as a rocket or aircraft, missile or bullet), an important problem is the determination of the… …
33Enumerative geometry — In mathematics, enumerative geometry is the branch of algebraic geometry concerned with counting numbers of solutions to geometric questions, mainly by means of intersection theory.HistoryThe problem of Apollonius is one of the earliest examples… …
34Transversality — in mathematics is a notion that describes how spaces can intersect; transversality can be seen as the opposite of tangency, and plays a role in general position. It formalizes the idea of a generic intersection in differential topology. It is… …
35Tusi-couple — The Tusi couple is a mathematical device in which a small circle rotates inside a larger circle twice the radius of the smaller circle. Rotations of the circles cause a point on the circumference of the smaller circle to oscillate back and forth… …
36Soddy's hexlet — [ ellipse.] In geometry, Soddy s hexlet is a chain of six spheres (shown in grey in Figure 1), each of which is tangent to both of its neighbors and also to three mutually tangent given spheres. In Figure 1, these three spheres are shown as an… …
37Johnson circles — In geometry, a set of Johnson circles comprise three circles of equal radius r sharing one common point of intersection H . In such a configuration the circles usually have a total of four intersections (points where at least two of them meet):… …
38Tangent circles — In geometry, tangent circles (also known as kissing circles) are circles that intersect in a single point. There are two types of tangency: internal and external. Many problems and constructions in geometry are related to tangent circles; such… …
39tractrix — noun The curve that satisfies the following property: That segment of the tangent line that lies between the point of tangency and a fixed line has length independent of the point of tangency chosen …
40tangent — [tan′jənt] adj. [L tangens, prp. of tangere, to touch: see TACT] 1. that touches; touching 2. Geom. touching and not intersecting a curve or curved surface at one and only one point: said of a line or plane n. [< ModL ( linea) tangens, tangent …
