vibrations per second 20

1) Naval: Hz

2) Engineering: cycles per second

3) Mathematics: Hz (сокращенная запись), cycle, period per second

4) Insurance: Hertz (Гц)

5) Physics: hertz

6) Electronics: cycle per second

7) Information technology: hertz (http://ivb.unact.ru/glossary/hz.html)

8) Sakhalin energy glossary: Hertz (Hz; Гц), hz (колебаний в секунду)

9) Polymers: periods per second

10) Chemical weapons: cycles per second (Гц)

11) Makarov: Hz ( hertz) (Гц), cps (cycle per second) (Hz) (Гц), cycle per second (Гц, период в секунду), cycle per second (cps) (Hz) (Гц), vibrations per second

12) Hi-Fi. Hz (Гц)

1) Engineering: (циклов) cycle per second, vibrations per second

2) Makarov: periods per second

1) General subject: vibrations per second 20

2) Mining: vibrations per minute

f vibration

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vibrazione s.f.

1 vibration, quivering: la vibrazione delle corde di uno strumento, the vibration of the strings of a musical instrument; le vibrazioni delle ali di un insetto, the quivering of an insect's wings

2 (fis., mecc.) vibration: vibrazione acustica, sonora, sound, sonorous vibration; vibrazione forzata, libera, forced, free vibration; vibrazione reticolare, lattice vibration; vibrazione aeroelastica, flutter; dieci vibrazioni al secondo, ten vibrations per second; senza vibrazioni, vibrationless (o vibration-proof).

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sostantivo femminile vibration

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vibrazione

/vibrat'tsjone/

sostantivo f.

vibration.

 

органы слуха
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[ http://www.eionet.europa.eu/gemet/alphabetic?langcode=en]

EN

hearing system
The system that is concerned with the perception of sound, is mediated through the organ of Corti of the ear in mammals or through corresponding sensory receptors of the lagena in lower vertebrates, is normally sensitive in man to sound vibrations between 16 and 27.000 cycles per second but most receptive to those between 2.000 and 5.000 cycles per second, is conducted centrally by the cochlear branch of the auditory nerve, and is coordinated especially in the medial geniculate body. (Source: WEBSTE)
[http://www.eionet.europa.eu/gemet/alphabetic?langcode=en]

Тематики

• охрана окружающей среды

EN

• hearing system

DE

• Gehörorgan

FR

• systčme auditif

SUBJECT AREA: Electronics and information technology, Horology

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Hetzel trained as an electrical engineer at the Federal Polytechnic in Zurich and worked for several years in the field of telecommunications before joining the Bulova Watch Company in 1950. At that time several companies were developing watches with electromagnetically maintained balances, but they represented very little advance on the mechanical watch and the mechanical switching mechanism was unreliable. In 1952 Hetzel started work on a much more radical design which was influenced by a transistorized tuning-fork oscillator that he had developed when he was working on telecommunications. Tuning forks, whose vibrations were maintained electromagnetically, had been used by scientists during the nineteenth century to measure small intervals of time, but Niaudet- Breguet appears to have been the first to use a tuning fork to control a clock. In 1866 he described a mechanically operated tuning-fork clock manufactured by the firm of Breguet, but it was not successful, possibly because the fork did not compensate for changes in temperature. The tuning fork only became a precision instrument during the 1920s, when elinvar forks were maintained in vibration by thermionic valve circuits. Their primary purpose was to act as frequency standards, but they might have been developed into precision clocks had not the quartz clock made its appearance very shortly afterwards. Hetzel's design was effectively a miniaturized version of these precision devices, with a transistor replacing the thermionic valve. The fork vibrated at a frequency of 360 cycles per second, and the hands were driven mechanically from the end of one of the tines. A prototype was working by 1954, and the watch went into production in 1960. It was sold under the tradename Accutron, with a guaranteed accuracy of one minute per month: this was a considerable improvement on the performance of the mechanical watch. However, the events of the 1920s were to repeat themselves, and by the end of the decade the Accutron was eclipsed by the introduction of quartz-crystal watches.

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SUBJECT AREA: Electricity, Electronics and information technology, Telecommunications

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At the age of 17 Hertz entered the Gelehrtenschule of the Johaneums in Hamburg, but he left the following year to obtain practical experience for a year with a firm of engineers in Frankfurt am Main. He then spent six months at the Dresden Technical High School, followed by year of military service in Berlin. At this point he decided to switch from engineering to physics, and after a year in Munich he studied physics under Helmholtz at the University of Berlin, gaining his PhD with high honours in 1880. From 1883 to 1885 he was a privat-dozent at Kiel, during which time he studied the electromagnetic theory of James Clerk Maxwell. In 1885 he succeeded to the Chair in Physics at Karlsruhe Technical High School. There, in 1887, he constructed a rudimentary transmitter consisting of two 30 cm (12 in.) rods with metal balls separated by a 7.5 mm (0.3 in.) gap at the inner ends and metallic plates at the outer ends, the whole assembly being mounted at the focus of a large parabolic metal mirror and the two rods being connected to an induction coil. At the other side of his laboratory he placed a 70 cm (27½ in.) diameter wire loop with a similar air gap at the focus of a second metal mirror. When the induction coil was made to create a spark across the transmitter air gap, he found that a spark also occurred at the "receiver". By a series of experiments he was not only able to show that the invisible waves travelled in straight lines and were reflected by the parabolic mirrors, but also that the vibrations could be refracted like visible light and had a similar wavelength. By this first transmission and reception of radio waves he thus confirmed the theoretical predictions made by Maxwell some twenty years earlier. It was probably in his experiments with this apparatus in 1887 that Hertz also observed that the voltage at which a spark was able to jump a gap was significantly reduced by the presence of ultraviolet light. This so-called photoelectric effect was subsequently placed on a theoretical basis by Albert Einstein in 1905. In 1889 he became Professor of Physics at the University of Bonn, where he continued to investigate the nature of electric discharges in gases at low pressure until his death after a long and painful illness. In recognition of his measurement of radio and other waves, the international unit of frequency of an oscillatory wave, the cycle per second, is now universally known as the Hertz.

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See also: Heaviside, Oliver

1) the state of happening often:

2) (in electricity, radio etc) the number of waves, vibrations etc per second:

3) a set wavelength on which radio stations regularly broadcast: