travelling-wave ratio
11Hippocampus — For other uses, see Hippocampus (disambiguation). Brain: Hippocampus The hippocampus is located in the medial temporal lobe of the brain. In this lateral view of the human brain, the frontal lobe is at le …
12Critical band — The term critical band, introduced by Harvey Fletcher in the 1940s, referred to the frequency bandwidth of the then loosely defined auditory filter. Psychophysiologically, beating and auditory roughness sensations can be linked to the inability… …
13Waveguide (electromagnetism) — In electromagnetics and communications engineering, the term waveguide may refer to any linear structure that guides electromagnetic waves. However, the original and most common meaning is a hollow metal pipe used for this purpose.A dielectric… …
14Components of jet engines — Diagram of a typical gas turbine jet engine. Air is compressed by the fan blades as it enters the engine, and it is mixed and burned with fuel in the combustion section. The hot exhaust gases provide forward thrust and turn the turbines which… …
15Speed 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… …
16optics — /op tiks/, n. (used with a sing. v.) the branch of physical science that deals with the properties and phenomena of both visible and invisible light and with vision. [1605 15; < ML optica < Gk optiká, n. use of neut. pl. of OPTIKÓS; see OPTIC,… …
17Redshift — This article is about the astronomical phenomenon. For other uses, see Redshift (disambiguation). Physical cosmology …
18Earth exploration — Introduction the investigation of the surface of the Earth and of its interior. By the beginning of the 20th century most of the Earth s surface had been explored, at least superficially, except for the Arctic and Antarctic regions. Today the… …
19Speed of sound — Sound is a vibration that travels through an elastic medium as a wave. The speed of sound describes how much distance such a wave travels in a certain amount of time. In SI Units with dry air at 20 °C (68 °F), the speed of sound is 343 m/s. This… …
20Dodge Dart — Manufacturer Chrysler Corporation Production 1960–1976 Predecessor Dodge Lancer (For compact version) …
