low-frequency oscillation
51sound — sound1 soundable, adj. /sownd/, n. 1. the sensation produced by stimulation of the organs of hearing by vibrations transmitted through the air or other medium. 2. mechanical vibrations transmitted through an elastic medium, traveling in air at a… …
52Sound — /sownd/, n. The, a strait between SW Sweden and Zealand, connecting the Kattegat and the Baltic. 87 mi. (140 km) long; 3 30 mi. (5 48 km) wide. Swedish and Danish, Oresund. * * * I Mechanical disturbance that propagates as a longitudinal wave… …
53electromagnetic radiation — Physics. radiation consisting of electromagnetic waves, including radio waves, infrared, visible light, ultraviolet, x rays, and gamma rays. [1950 55] * * * Energy propagated through free space or through a material medium in the form of… …
54electron tube — an electronic device that consists, typically, of a sealed glass bulb containing two or more electrodes: used to generate, amplify, and rectify electric oscillations and alternating currents. Also called electronic tube. Cf. gas tube, vacuum tube …
55Vibration — For the soul music group, see The Vibrations. For the machining context, see Machining vibrations. For the albums, see Vibrations (Roy Ayers album) and Vibrations (The Three Sounds album). Classical mechanics …
56Ionosphere — The ionosphere is a part of the upper atmosphere, comprising portions of the mesosphere, thermosphere and exosphere, distinguished because it is ionized by solar radiation. It plays an important part in atmospheric electricity and forms the inner …
57Climatology — Climate Research redirects here. For the journal of that name, see Climate Research (journal). Atmospheric sciences …
58Positive feedback — Alarm or panic can spread by positive feedback among a herd of animals to cause a stampede. Positive feedback is energy taken from the output of a system and reapplied to the input, which is phase congruent with the input signal. A system… …
59Tuned mass damper — An animation showing the movement of a skyscraper versus the mass damper. The green indicates the hydraulic cylinders used to damp the motion of the skyscraper. A tuned mass damper, also known as an active mass damper (AMD) or harmonic absorber,… …
60Guitar effects — are electronic devices that modify the tone, pitch, or sound of an electric guitar, or condition or reroute the signal in some fashion. Effects can be housed in small effects pedals ( stomp boxes ), guitar amplifiers, guitar amplifier simulation… …
