section in direction of the cone axis
51Area rule — The Whitcomb area rule, also called the transonic area rule, is a design technique used to reduce an aircraft s drag at transonic and supersonic speeds, particularly between Mach 0.75 and 1.2. This is one of the most important operating speed… …
52Equation of time — The equation of time is the difference over the course of a year between time as read from a sundial and time as read from a clock, measured in an ideal situation (ie. in a location at the centre of a time zone, and which does not use daylight… …
53Traffic light — The traffic light, also known as traffic signal, stop light, traffic lamp, stop and go lights, robot or semaphore, is a signaling device positioned at a road intersection, pedestrian crossing, or other location. Its purpose is to indicate, using… …
54Speed of light — The speed of light in the vacuum of free space is an important physical constant usually denoted by the letter c . [NIST and BIPM practice is to use c 0 for the speed of light in vacuum in accord with international standard ISO 31 5. See… …
55List of gear nomenclature — Gears have a wide range of unique terminology known as gear nomenclature. Many of the terms defined cite the same reference work.[1] Contents 1 Addendum 2 Addendum angle 3 Addendum circle …
56eye, human — ▪ anatomy Introduction specialized sense organ capable of receiving visual images, which are then carried to the brain. Anatomy of the visual apparatus Structures auxiliary to the eye The orbit The eye is protected from mechanical injury… …
57Sundial — A sundial is a device that measures time by the position of the Sun. In common designs such as the horizontal sundial, the sun casts a shadow from its style (a thin rod or a sharp, straight edge) onto a flat surface marked with lines indicating… …
58Hyperbola — This article is about a geometrical curve, a conic section. For the term used in rhetoric, see Hyperbole …
59Ellipse — Elliptical redirects here. For the exercise machine, see Elliptical trainer. This article is about the geometric figure. For other uses, see Ellipse (disambiguation). Not to be confused with ellipsis. An ellipse obtained as the intersection of a… …
60Gear — For the gear like device used to drive a roller chain, see Sprocket. This article is about mechanical gears. For other uses, see Gear (disambiguation). Two meshing gears transmitting rotational motion. Note that the smaller gear is rotating… …
