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One voltage cycle of a three-phase system. A polyphase system (the term coined by Silvanus Thompson) is a means of distributing alternating-current (AC) electrical power that utilizes more than one AC phase, which refers to the phase offset value (in degrees) between AC in multiple conducting wires; phases may also refer to the corresponding terminals and conductors, as in color codes.
Mr. Baily had very clear views as to how far this really represented a rotatory magnetic field.His own words are as follows: [2] "The rotation of the disk is due to that of the magnetic field in which it is suspended; and we should expect that if a similar motion of the field could be produced by any other means the result would be a similar motion of the disk."
The resulting source of polyphase power soon found widespread acceptance. The invention of the polyphase alternator is key in the history of electrification, as is the power transformer . These inventions enabled power to be transmitted by wires economically over considerable distances.
In 1886 the inventor Nikola Tesla demonstrated a polyphase brushless AC induction motor also based on a rotating magnetic field. In July 1888, George Westinghouse licensed Nikola Tesla's American patents for the induction motor and transformer designs.
Polyphase coils are electromagnetic coils connected together in a polyphase system such as a generator or motor. In modern systems, the number of phases is usually three or a multiple of three. Each phase carries a sinusoidal alternating current whose phase is delayed relative to one of its neighbours and advanced relative to its other ...
Groups of motor units often work together as a motor pool to coordinate the contractions of a single muscle. The concept was proposed by Charles Scott Sherrington. [2] Usually muscle fibers in a motor unit are of the same fiber type. [3] When a motor unit is activated, all of its fibers contract.
Myosins are a superfamily of actin motor proteins that convert chemical energy in the form of ATP to mechanical energy, thus generating force and movement. The first identified myosin, myosin II, is responsible for generating muscle contraction. Myosin II is an elongated protein that is formed from two heavy chains with motor heads and two ...
Page of one of the first works of Biomechanics (De Motu Animalium of Giovanni Alfonso Borelli) in the 17th centuryBiomechanics is the study of the structure, function and motion of the mechanical aspects of biological systems, at any level from whole organisms to organs, cells and cell organelles, [1] using the methods of mechanics. [2]