frequency of normal vibrations
101Classical guitar making — A person who is specialized in the making of stringed instruments such as guitars, lutes and violins is called a luthier. Contents 1 Skills 1.1 Shaping of wood with acoustics and resonance aims 1.2 Sound characteristics (Timbre) …
102Medical ultrasonography — This article is about using ultrasound to image the human body. For imaging of animals in research, see Preclinical imaging. Sonography redirects here. For the tactile alphabet called sonography , see Night writing. Medical ultrasonography… …
103theory — A reasoned explanation of known facts or phenomena that serves as a basis of investigation by which to seek the truth. SEE ALSO: hypothesis, postulate. [G. theoria, a beholding, speculation, t., fr. theoros, a beholder] adsorption t. of narcosis… …
104Tuvan throat singing — The Alash Ensemble Tuvan throat singing is one particular variant of overtone singing practiced by the Tuva people of southern Siberia. The art of Tuvan throat singing is a style in which one or more pitches sound simultaneously over a… …
105Partial differential equation — A visualisation of a solution to the heat equation on a two dimensional plane In mathematics, partial differential equations (PDE) are a type of differential equation, i.e., a relation involving an unknown function (or functions) of several… …
106Stuxnet — is a computer worm discovered in June 2010. It targets Siemens industrial software and equipment running Microsoft Windows.[1] While it is not the first time that hackers have targeted industrial systems,[2] it is the first discovered malware… …
107Hard disk drive — Hard drive redirects here. For other uses, see Hard drive (disambiguation). Hard disk drive Mechanical interior of a modern hard disk drive Date invented 24 December 1954 [1] …
108Headphones — For other uses, see Headphones (disambiguation). Sennheiser HD555 headphones, used in audio production environments …
109Purr — For other uses, see Purr (disambiguation). A purr is a sound made by all species of felids and is a part of cat communication. It varies between cats (for example by loudness and tone), and from species to species, but can be characterized as a… …
110Engine balance — is the design, construction and tuning of an engine to run smoothly. Engine balance reduces vibration and other stresses, and may improve the performance, efficiency, cost of ownership and reliability of the engine, as well as reducing the stress …
