31. Unlike eigenaxis fixed axis and maneuver rate rotations, ZPM rotations vary the rotation axis and maneuver rate during the maneuver. 32. Sarabauite is of the 2 / m crystal class; it has a 2 fold rotation axis perpendicular to a mirror plane. 33. Thus we can extract from any 3? rotation matrix a rotation axis and an angle, and these completely determine the rotation. 34. Any motion in / on the Earth causes a slowdown or speedup of the rotation, or a change of rotation axis . 35. The front face should lie precisely in the plane of the elevation rotation axis to minimize the required flat mirror aperture. 36. Monoclinic minerals contain a twofold rotation axis where they can be rotated 360?and have the crystal face repeat every 180? 37. "Spin " is a non classical property of elementary particles, since angular momenta of the object's constituents about the rotation axis . 38. As gyroscopes keep their rotation axis constant, angles measured in a gyro frame are equivalent to angles measured in the lab frame. 39. Where is the position vector of the particle ( radial from the rotation axis ) and the tangential velocity of the particle. 40. This can be done if the rotation axis can be unambiguously obtained from the combination of symmetry elements presented in the symbol.
