ever sinvce the dawn of civilization, productivity as a fact has always existed, it, however, appeared as a process of economic thought at the end of the 18th century with the onset of industrial revolution and at a time when famines were frequent
electric energy or power is produced by special plant housed in structures comprising what are called power stations and with
Diseases of warm lands are a peculiar field of pathology that has long been set apart as a separate discipline
metal alloys consist of various elements metals and metalloids (carbon, silicon, phosphorus, sulphur etc) the principal element in an alloy is the metal which imparts the metallic nature to the entire alloy
the producta of the engineering industries are utilised by all branches of the national economy
there are a great many forms of motion. an incalculable number of bodies are in motion on the earth
the idea of replacing opaque leukomatous tissue by a transparent corneal graft was conceived at the beginning of the nineteenth century
The steam turbine is a prime mover in which the potential energy of the steam is transformed into kinetic energy and the latter in its turn is transformed into the mechanical energy of rotation of the turbine shaft.
As a result of their use in service, parts of engines, machinery, and ship installations lose, wholly or partly, their original quality; this disturbs their operation and calls for repairs.