(any mechanical driving device)
71performing arts — arts or skills that require public performance, as acting, singing, or dancing. [1945 50] * * * ▪ 2009 Introduction Music Classical. The last vestiges of the Cold War seemed to thaw for a moment on Feb. 26, 2008, when the unfamiliar strains …
72railroad — /rayl rohd /, n. 1. a permanent road laid with rails, commonly in one or more pairs of continuous lines forming a track or tracks, on which locomotives and cars are run for the transportation of passengers, freight, and mail. 2. an entire system… …
73arts, East Asian — Introduction music and visual and performing arts of China, Korea, and Japan. The literatures of these countries are covered in the articles Chinese literature, Korean literature, and Japanese literature. Some studies of East Asia… …
74energy conversion — ▪ technology Introduction the transformation of energy from forms provided by nature to forms that can be used by humans. Over the centuries a wide array of devices and systems has been developed for this purpose. Some of these energy …
75List of words having different meanings in British and American English: A–L — Differences between American and British English American English …
76Electronic amplifier — A practical amplifier circuit An electronic amplifier is a device for increasing the power of a signal. It does this by taking energy from a power supply and controlling the output to match the input signal shape but with a larger amplitude. In… …
77cell — cell1 cell like, adj. /sel/, n. 1. a small room, as in a convent or prison. 2. any of various small compartments or bounded areas forming part of a whole. 3. a small group acting as a unit within a larger organization: a local cell of the… …
78Earth Sciences — ▪ 2009 Introduction Geology and Geochemistry The theme of the 33rd International Geological Congress, which was held in Norway in August 2008, was “Earth System Science: Foundation for Sustainable Development.” It was attended by nearly… …
79Physical Sciences — ▪ 2009 Introduction Scientists discovered a new family of superconducting materials and obtained unique images of individual hydrogen atoms and of a multiple exoplanet system. Europe completed the Large Hadron Collider, and China and India took… …
80Perpetual motion — For other uses, see Perpetual motion (disambiguation). Robert Fludd s 1618 water screw perpetual motion machine from a 1660 wood engraving. This device is widely credited as the first recorded attempt to describe such a device in order to produce …
