rotation-inversion axis — /roh tay sheuhn in verr zheuhn, sheuhn/, Crystall. an axis of a crystal such that rotating about the axis and then inverting the crystal brings the crystal back to its original position. Also called symmetry axis of rotary inversion. Cf. symmetry … Useful english dictionary
Rotation (mathematics) — Rotation of an object in two dimensions around a point O. In geometry and linear algebra, a rotation is a transformation in a plane or in space that describes the motion of a rigid body around a fixed point. A rotation is different from a… … Wikipedia
symmetry axis of rotary inversion — Crystall. See rotation inversion axis. * * * … Universalium
symmetry axis of rotary inversion — Crystall. See rotation inversion axis … Useful english dictionary
Inversion in a point — In Euclidean geometry, the inversion of a point X in respect to a point P is a point X * such that P is the midpoint of the line segment with endpoints X and X *. In other words, the vector from X to P is the same as the vector from P to X *.The… … Wikipedia
Improper rotation — In 3D geometry, an improper rotation, also called rotoreflection or rotary reflection is, depending on context, a linear transformation or affine transformation which is the combination of a rotation about an axis and an inversion about the… … Wikipedia
Matrices de rotation — Matrice de rotation En mathématiques, et plus précisément en algèbre linéaire, une matrice de rotation est une matrice orthogonale de déterminant 1. Le nom est dû au fait qu une matrice de rotation n×n correspond à une rotation géométrique autour … Wikipédia en Français
Matrice de rotation — En mathématiques, et plus précisément en algèbre linéaire, une matrice de rotation Q est une matrice orthogonale de déterminant 1, ce qui peut s exprimer par les équations suivantes : QtQ = I = QQt et det Q = 1, où Qt est la matrice… … Wikipédia en Français
Differential rotation — is seen when different parts of a rotating object move with different angular velocities (rates of rotation) at different latitudes and/or depths of the body and/or in time. This indicates that the object is not solid. In fluid objects, such as… … Wikipedia
Differential rotation in stars — What is differential rotation? *Differential rotation is when a rotating body has different angular velocities at different latitudes and/or depths of the body and/or in time. Differential rotation can be applied to any type of fluid body such as … Wikipedia