vibration recording
81Speed 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… …
82Ballast tamper — A ballast tamper or tamping machine is a machine used to pack (or tamp) the track ballast under railway tracks to make the tracks more durable. Prior to the introduction of mechanical tampers, this task was done by manual labour with the help of… …
83La Bayadère — ( The Temple Dancer ) (RussianБаядерка Bayaderka ) is a ballet, originally staged in four acts and seven scenes, choreographed by the balletmaster Marius Petipa to the music of Ludwig Minkus. It was first performed by the Imperial Ballet at the… …
84Christian Scott — Christian Scott; North Sea Jazz Festival 2007 Photo: Evert Jan Hielema Background information Birth name Christian Scott …
85Acoustic quieting — This article primarily discusses mechanical and acoustic noise. See Noise reduction for electronic noise. : For noise masking by saturation, see Sound masking or pink noise.Acoustic quieting is the process of making machinery quieter by damping… …
86nervous system disease — Introduction any of the diseases or disorders that affect the functioning of the human nervous system (nervous system, human). Everything that humans sense, consider, and effect and all the unlearned reflexes of the body depend on the… …
87Clavichord — 1977 clavichord by Keith Hill, Op. 44 (Op. 28 reworked) Keyboard instrument Hornbostel–Sachs classification 314.122 4 8 (Simple chordophone with keyboard sounded by tangents) …
88Astrophotography — An image of Orion s Belt composited from digitized black and white photographic plates recorded through red and blue astronomical filters, with a computer synthesized green channel. The plates were taken using the Samuel Oschin Telescope between… …
89Sound reinforcement system — A sound reinforcement system is an arrangement of microphones, electronic signal processors, amplifiers, and loudspeakers that makes live or pre recorded sounds usually music or speech louder, or that distributes the sound to a larger or more… …
90Architectural acoustics — is the science of noise control within buildings. The first application of architectural acoustics was in the design of opera houses and then concert halls. More widely, noise suppression is critical in the design of multi unit dwellings and… …
