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1 Hertz, Heinrich Rudolph
[br]b. 22 February 1857 Hamburg, Germanyd. 1 January 1894 Bonn, Germany[br]German physicist who was reputedly the first person to transmit and receive radio waves.[br]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.[br]Principal Honours and DistinctionsRoyal Society Rumford Medal 1890.BibliographyMuch of Hertz's work, including his 1890 paper "On the fundamental equations of electrodynamics for bodies at rest", is recorded in three collections of his papers which are available in English translations by D.E.Jones et al., namely Electric Waves (1893), Miscellaneous Papers (1896) and Principles of Mechanics (1899).Further ReadingJ.G.O'Hara and W.Pricha, 1987, Hertz and the Maxwellians, London: Peter Peregrinus. J.Hertz, 1977, Heinrich Hertz, Memoirs, Letters and Diaries, San Francisco: San Francisco Press.R.Appleyard, 1930, Pioneers of Electrical Communication.See also: Heaviside, OliverKFBiographical history of technology > Hertz, Heinrich Rudolph
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2 Hertz
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3 hertz
[həːts] plural hertz noun هيرْتز: وِحْدَة التردُّد -
4 Hertz'sche Wellen
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5 hertz dalgaları
n. Hertzian waves -
6 электромагнитные волны
Русско-английский словарь по строительству и новым строительным технологиям > электромагнитные волны
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7 електромагнитен вълна
hertz waveshertzian wavesБългарски-Angleščina политехнически речник > електромагнитен вълна
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8 волна
waveволны АльвенаAlfven wavesволна возмущенийdisturbance waveволны в полутениpenumbral wavesволны в солнечном ветреsolar wind wavesволны де Бройляde Broglie wavesволна интенсивностиintensity waveволны космического происхожденияextraterrestrial wavesволны ЛенгмюраLangmuir wavesволны материи1.matter waves 2.de Broglie wavesволна МоретонаMoreton waveволна отраженная от Землиground-reflected waveволна плотностиdensity waveволна разрежения1.expansion wave 2.rarefaction waveволны сжатияcompression(al) wavesатмосферные волныatmospheric wavesбыстрая ударная волнаfast shock (in solar wind)взрывная волнаblast wave (in solar wind)взрывная вспышечная волнаblast flare waveвзрывная ударная волнаexplosion shockвспышечная взрывная волнаflare blast waveголовная ударная волнаforeward shockгравитационная волна1.gravitational wave 2.gravity waveгравитационные внутренние волныinternal gravity wavesзвездные ударные волныstellar shock wavesкосмические радиоволныcosmic radio wavesлунная приливная волнаlunar tidal waveлунно-солнечная суточная волнаluni-solar diurnal waveмагнитогидродинамическая волна1.hydromagnetic wave 2.magnetohydrodynamic waveмагнитогидродинамическая волна сжатия1.compression(al) dilatation wave 2.Alfven waveнебесная волна1.sky wave 2.space waveнейтронные волныneutron wavesнеоднородная волнаinhomogeneous waveобратная ударная волнаreverse shockосновная лунная волнаprincipal lunar waveосновная солнечная волнаprincipal solar waveотраженная волнаrefracted waveплазменная волнаplasma waveполусуточная волнаsemidiurnal waveпоршневая волнаdriven waveпреломленная волнаrefracted waveприливная волнаtidal waveприливная волна в атмосфереatmospheric tidal waveпространственная волна1.indirect wave 2.space waveрассеянная волнаscattered waveсветовая волнаlight waveсейсмическая волнаEarth (quake) waveстоячая ударная волнаstanding bow shockударная волнаshock waveударная волна сжатияcompression shock waveчеренковские плазменные волныCerenkov plasma wavesэлектромагнитные волны1.electromagnetic waves 2.Hertz wavesэлектромагнитная волна космического происхожденияnatural wave -
9 волны Герца
1) Physics: Hertzian radiation2) Makarov: Hertz wave (электромагнитные), Hertz waves, Hertzian wave (электромагнитные), Hertzian waves -
10 радиоволны
1) General subject: radio waves2) Engineering: Hertz waves, Hertzian waves3) Physics: radiowaves4) Mass media: airwaves5) Makarov: broadcast waves, radio wave -
11 электромагнитные волны
1) General subject: electromagnetic waves2) Physics: Hertzian waves3) Makarov: Hertz waves, electromagnetic radiationУниверсальный русско-английский словарь > электромагнитные волны
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12 волны Герца
Hertzian waves, Hertz waves -
13 радиоволны
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14 Branly, Edouard Eugène
[br]b. 23 October 1844 Amiens, Franced. 24 March 1940 Paris, France[br]French electrical engineer, who c.1890 invented the coherer for detecting radio waves.[br]Branly received his education at the Lycée de Saint Quentin in the Département de l'Aisne and at the Henri IV College of Paris University, where he became a Fellow of the University, graduating as a Doctor of Physics in 1873. That year he was appointed a professor at the College of Bourges and Director of Physics Instruction at the Sorbonne. Three years later he moved to the Free School in Paris as Professor of Advanced Studies. In addition to these responsibilities, he qualified as an MD in 1882 and practised medicine from 1896 to 1916. Whilst carrying out experiments with Hertzian (radio) waves in 1890, Branly discovered that a tube of iron filings connected to a source of direct voltage only became conductive when the radio waves were present. This early form of rectifier, which he called a coherer and which needed regular tapping to maintain its response, was used to operate a relay when the waves were turned on and off by Morse signals, thus providing the first practical radio communication.[br]Principal Honours and DistinctionsPapal Order of Commander of St George 1899. Légion d'honneur, Chevalier 1900, Commandeur 1925. Osiris Prize (jointly with Marie Curie) 1903. Argenteuil Prize and Associate of the Royal Belgian Academy 1910. Member of the Academy of Science 1911. State Funeral at Notre Dame Cathedral.BibliographyAmongst his publications in Comptes rendus were "Conductivity of mediocre conductors", "Conductivity of gases", "Telegraphic conduction without wires" and "Conductivity of imperfect conductors realised at a distance by wireless by spark discharge of a capacitor".Further ReadingE.Hawkes, 1927, Pioneers of Wireless, London: Methuen. E.Larien, 1971, A History of Invention, London: Victor Gollancz.V.J.Phillips: 1980, Early Radio Wave Detectors, London: Peter Peregrinus.KF -
15 Maxwell, James Clerk
[br]b. 13 June 1831 Edinburgh, Scotlandd. 5 November 1879 Cambridge, England[br]Scottish physicist who formulated the unified theory of electromagnetism, the kinetic theory of gases and a theory of colour.[br]Maxwell attended school at the Edinburgh Academy and at the age of 16 went on to study at Edinburgh University. In 1850 he entered Trinity College, Cambridge, where he graduated four years later as Second Wrangler with the award of the Smith's Prize. Two years later he was appointed Professor at Marischal College, Aberdeen, where he married the Principal's daughter. In 1860 he moved to King's College London, but on the death of his father five years later, Maxwell returned to the family home in Scotland, where he continued his researches as far as the life of a gentleman farmer allowed. This rural existence was interrupted in 1874 when he was persuaded to accept the chair of Cavendish Professor of Experimental Physics at Cambridge. Unfortunately, in 1879 he contracted the cancer that brought his brilliant career to an untimely end. While at Cambridge, Maxwell founded the Cavendish Laboratory for research in physics. A succession of distinguished physicists headed the laboratory, making it one of the world's great centres for notable discoveries in physics.During the mid-1850s, Maxwell worked towards a theory to explain electrical and magnetic phenomena in mathematical terms, culminating in 1864 with the formulation of the fundamental equations of electromagnetism (Maxwell's equations). These equations also described the propagation of light, for he had shown that light consists of transverse electromagnetic waves in a hypothetical medium, the "ether". This great synthesis of theories uniting a wide range of phenomena is worthy to set beside those of Sir Isaac Newton and Einstein. Like all such syntheses, it led on to further discoveries. Maxwell himself had suggested that light represented only a small part of the spectrum of electromagnetic waves, and in 1888 Hertz confirmed the discovery of another small part of the spectrum, radio waves, with momentous implications for the development of telecommunication technology. Maxwell contributed to the kinetic theory of gases, which by then were viewed as consisting of a mass of randomly moving molecules colliding with each other and with the walls of the containing vessel. From 1869 Maxwell applied statistical methods to describe the molecular motion in mathematical terms. This led to a greater understanding of the behaviour of gases, with important consequences for the chemical industry.Of more direct technological application was Maxwell's work on colour vision, begun in 1849, showing that all colours could be derived from the three primary colours, red, yellow and blue. This enabled him in 1861 to produce the first colour photograph, of a tartan. Maxwell's discoveries about colour vision were quickly taken up and led to the development of colour printing and photography.[br]BibliographyMost of his technical papers are reprinted in The Scientific Papers of J.Clerk Maxwell, 1890, ed. W.D.Niven, Cambridge, 2 vols; reprinted 1952, New York.Maxwell published several books, including Theory of Heat, 1870, London (1894, 11th edn, with notes by Lord Rayleigh) and Theory of Electricity and Magnetism, 1873, Oxford (1891, ed. J.J.Thomson, 3rd edn).Further ReadingL.Campbell and W.Garnett, 1882, The Life of James Clerk Maxwell, London (the standard biography).J.J.Thomson (ed.), 1931, James Clerk Maxwell 1831–1931, Cambridge. J.G.Crowther, 1932, British Scientists of the Nineteenth Century, London.LRD -
16 Marconi, Marchese Guglielmo
[br]b. 25 April 1874 Bologna, Italyd. 20 July 1937 Rome, Italy[br]Italian radio pioneer whose inventiveness and business skills made radio communication a practical proposition.[br]Marconi was educated in physics at Leghorn and at Bologna University. An avid experimenter, he worked in his parents' attic and, almost certainly aware of the recent work of Hertz and others, soon improved the performance of coherers and spark-gap transmitters. He also discovered for himself the use of earthing and of elevated metal plates as aerials. In 1895 he succeeded in transmitting telegraphy over a distance of 2 km (1¼ miles), but the Italian Telegraph authority rejected his invention, so in 1896 he moved to England, where he filed the first of many patents. There he gained the support of the Chief Engineer of the Post Office, and by the following year he had achieved communication across the Bristol Channel.The British Post Office was also slow to take up his work, so in 1897 he formed the Wireless Telegraph \& Signal Company to work independently. In 1898 he sold some equipment to the British Army for use in the Boer War and established the first permanent radio link from the Isle of Wight to the mainland. In 1899 he achieved communication across the English Channel (a distance of more than 31 miles or 50 km), the construction of a wireless station at Spezia, Italy, and the equipping of two US ships to report progress in the America's Cup yacht race, a venture that led to the formation of the American Marconi Company. In 1900 he won a contract from the British Admiralty to sell equipment and to train operators. Realizing that his business would be much more successful if he could offer his customers a complete radio-communication service (known today as a "turnkey" deal), he floated a new company, the Marconi International Marine Communications Company, while the old company became the Marconi Wireless Telegraph Company.His greatest achievement occurred on 12 December 1901, when Morse telegraph signals from a transmitter at Poldhu in Cornwall were received at St John's, Newfoundland, a distance of some 2,100 miles (3,400 km), with the use of an aerial flown by a kite. As a result of this, Marconi's business prospered and he became internationally famous, receiving many honours for his endeavours, including the Nobel Prize for Physics in 1909. In 1904, radio was first used to provide a daily bulletin at sea, and in 1907 a transatlantic wireless telegraphy service was inaugurated. The rescue of 1,650 passengers from the shipwreck of SS Republic in 1909 was the first of many occasions when wireless was instrumental in saving lives at sea, most notable being those from the Titanic on its maiden voyage in April 1912; more lives would have been saved had there been sufficient lifeboats. Marconi was one of those who subsequently pressed for greater safety at sea. In 1910 he demonstrated the reception of long (8 km or 5 miles) waves from Ireland in Buenos Aires, but after the First World War he began to develop the use of short waves, which were more effectively reflected by the ionosphere. By 1918 the first link between England and Australia had been established, and in 1924 he was awarded a Post Office contract for short-wave communication between England and the various parts of the British Empire.With his achievements by then recognized by the Italian Government, in 1915 he was appointed Radio-Communications Adviser to the Italian armed forces, and in 1919 he was an Italian delegate to the Paris Peace Conference. From 1921 he lived on his yacht, the Elettra, and although he joined the Fascist Party in 1923, he later had reservations about Mussolini.[br]Principal Honours and DistinctionsNobel Prize for Physics (jointly with K.F. Braun) 1909. Russian Order of S t Anne. Commander of St Maurice and St Lazarus. Grand Cross of the Order of the Crown (i.e. Knight) of Italy 1902. Freedom of Rome 1903. Honorary DSc Oxford. Honorary LLD Glasgow. Chevalier of the Civil Order of Savoy 1905. Royal Society of Arts Albert Medal. Honorary knighthood (GCVO) 1914. Institute of Electrical and Electronics Engineers Medal of Honour 1920. Chairman, Royal Society of Arts 1924. Created Marquis (Marchese) 1929. Nominated to the Italian Senate 1929. President, Italian Academy 1930. Rector, University of St Andrews, Scotland, 1934.Bibliography1896, "Improvements in transmitting electrical impulses and in apparatus thereof", British patent no. 12,039.1 June 1898, British patent no. 12,326 (transformer or "jigger" resonant circuit).1901, British patent no. 7,777 (selective tuning).1904, British patent no. 763,772 ("four circuit" tuning arrangement).Further ReadingD.Marconi, 1962, My Father, Marconi.W.J.Baker, 1970, A History of the Marconi Company, London: Methuen.KFBiographical history of technology > Marconi, Marchese Guglielmo
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17 и более
. и выше•Ultrasonic waves with frequencies of a billion hertz and up (or over, or more) are capable of travelling several centimetres through a solid medium.
Русско-английский научно-технический словарь переводчика > и более
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18 и более
. и выше•Ultrasonic waves with frequencies of a billion hertz and up (or over, or more) are capable of travelling several centimetres through a solid medium.
Русско-английский научно-технический словарь переводчика > и более
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19 Lodge, Sir Oliver Joseph
[br]b. 12 June 1851 Penkhull, Staffordshire, Englandd. 22 August 1940 Lake, near Salisbury, Wiltshire, England[br]English physicist who perfected Branly's coherer; said to have given the first public demonstration of wireless telegraphy.[br]At the age of 8 Lodge entered Newport Grammar School, and in 1863–5 received private education at Coombs in Suffolk. He then returned to Staffordshire, where he assisted his father in the potteries by working as a book-keeper. Whilst staying with an aunt in London in 1866–7, he attended scientific lectures and became interested in physics. As a result of this and of reading copies of English Mechanic magazine, when he was back home in Hanley he began to do experiments and attended the Wedgewood Institute. Returning to London c. 1870, he studied initially at the Royal College of Science and then, from 1874, at University College, London (UCL), at the same time attending lectures at the Royal Institution.In 1875 he obtained his BSc, read a paper to the British Association on "Nodes and loops in chemical formulae" and became a physics demonstrator at UCL. The following year he was appointed a physics lecturer at Bedford College, completing his DSc in 1877. Three years later he became Assistant Professor of Mathematics at UCL, but in 1881, after only two years, he accepted the Chair of Experimental Physics at the new University College of Liverpool. There began a period of fruitful studies of electricity and radio transmission and reception, including development of the lightning conductor, discovery of the "coherent" effect of sparks and improvement of Branly's coherer, and, in 1894, what is said to be the first public demonstration of the transmission and reception (using a coherer) of wireless telegraphy, from Lewis's department store to the clock tower of Liverpool University's Victoria Building. On 10 May 1897 he filed a patent for selective tuning by self-in-ductance; this was before Marconi's first patent was actually published and its priority was subsequently upheld.In 1900 he became the first Principal of the new University of Birmingham, where he remained until his retirement in 1919. In his later years he was increasingly interested in psychical research.[br]Principal Honours and DistinctionsKnighted 1902. FRS 1887. Royal Society Council Member 1893. President, Society for Psychical Research 1901–4, 1932. President, British Association 1913. Royal Society Rumford Medal 1898. Royal Society of Arts Albert Medal 1919. Institution of Electrical Engineers Faraday Medal 1932. Fourteen honorary degrees from British and other universities.Bibliography1875, "The flow of electricity in a plane", Philosophical Magazine (May, June and December).1876, "Thermo-electric phenomena", Philosophical Magazine (December). 1888, "Lightning conductors", Philosophical Magazine (August).1889, Modern Views of Electricity (lectures at the Royal Institution).10 May 1897, "Improvements in syntonized telegraphy without line wires", British patent no. 11,575, US patent no. 609,154.1898, "Radio waves", Philosophical Magazine (August): 227.1931, Past Years, An Autobiography, London: Hodder \& Stoughton.Further ReadingW.P.Jolly, 1974, Sir Oliver Lodge, Psychical Resear cher and Scientist, London: Constable.E.Hawks, 1927, Pioneers of Wireless, London: Methuen.See also: Hertz, Heinrich RudolphKFBiographical history of technology > Lodge, Sir Oliver Joseph
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20 Preece, Sir William Henry
[br]b. 15 February 1834 Bryn Helen, Gwynedd, Walesd. 6 November 1913 Penrhos, Gwynedd, Wales[br]Welsh electrical engineer who greatly furthered the development and use of wireless telegraphy and the telephone in Britain, dominating British Post Office engineering during the last two decades of the nineteenth century.[br]After education at King's College, London, in 1852 Preece entered the office of Edwin Clark with the intention of becoming a civil engineer, but graduate studies at the Royal Institution under Faraday fired his enthusiasm for things electrical. His earliest work, as connected with telegraphy and in particular its application for securing the safe working of railways; in 1853 he obtained an appointment with the Electric and National Telegraph Company. In 1856 he became Superintendent of that company's southern district, but four years later he moved to telegraph work with the London and South West Railway. From 1858 to 1862 he was also Engineer to the Channel Islands Telegraph Company. When the various telegraph companies in Britain were transferred to the State in 1870, Preece became a Divisional Engineer in the General Post Office (GPO). Promotion followed in 1877, when he was appointed Chief Electrician to the Post Office. One of the first specimens of Bell's telephone was brought to England by Preece and exhibited at the British Association meeting in 1877. From 1892 to 1899 he served as Engineer-in-Chief to the Post Office. During this time he made a number of important contributions to telegraphy, including the use of water as part of telegraph circuits across the Solent (1882) and the Bristol Channel (1888). He also discovered the existence of inductive effects between parallel wires, and with Fleming showed that a current (thermionic) flowed between the hot filament and a cold conductor in an incandescent lamp.Preece was distinguished by his administrative ability, some scientific insight, considerable engineering intuition and immense energy. He held erroneous views about telephone transmission and, not accepting the work of Oliver Heaviside, made many errors when planning trunk circuits. Prior to the successful use of Hertzian waves for wireless communication Preece carried out experiments, often on a large scale, in attempts at wireless communication by inductive methods. These became of historic interest only when the work of Maxwell and Hertz was developed by Guglielmo Marconi. It is to Preece that credit should be given for encouraging Marconi in 1896 and collaborating with him in his early experimental work on radio telegraphy.While still employed by the Post Office, Preece contributed to the development of numerous early public electricity schemes, acting as Consultant and often supervising their construction. At Worcester he was responsible for Britain's largest nineteenth-century public hydro-electric station. He received a knighthood on his retirement in 1899, after which he continued his consulting practice in association with his two sons and Major Philip Cardew. Preece contributed some 136 papers and printed lectures to scientific journals, ninety-nine during the period 1877 to 1894.[br]Principal Honours and DistinctionsCB 1894. Knighted (KCB) 1899. FRS 1881. President, Society of Telegraph Engineers, 1880. President, Institution of Electrical Engineers 1880, 1893. President, Institution of Civil Engineers 1898–9. Chairman, Royal Society of Arts 1901–2.BibliographyPreece produced numerous papers on telegraphy and telephony that were presented as Royal Institution Lectures (see Royal Institution Library of Science, 1974) or as British Association reports.1862–3, "Railway telegraphs and the application of electricity to the signaling and working of trains", Proceedings of the ICE 22:167–93.Eleven editions of Telegraphy (with J.Sivewright), London, 1870, were published by 1895.1883, "Molecular radiation in incandescent lamps", Proceedings of the Physical Society 5: 283.1885. "Molecular shadows in incandescent lamps". Proceedings of the Physical Society 7: 178.1886. "Electric induction between wires and wires", British Association Report. 1889, with J.Maier, The Telephone.1894, "Electric signalling without wires", RSA Journal.1898, "Aetheric telegraphy", Proceedings of the Institution of Electrical Engineers.Further ReadingJ.J.Fahie, 1899, History of Wireless Telegraphy 1838–1899, Edinburgh: Blackwood. E.Hawkes, 1927, Pioneers of Wireless, London: Methuen.E.C.Baker, 1976, Sir William Preece, F.R.S. Victorian Engineer Extraordinary, London (a detailed biography with an appended list of his patents, principal lectures and publications).D.G.Tucker, 1981–2, "Sir William Preece (1834–1913)", Transactions of the Newcomen Society 53:119–36 (a critical review with a summary of his consultancies).GW / KFBiographical history of technology > Preece, Sir William Henry
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См. также в других словарях:
Hertz: Der Vater der Funktechnik — Im Herbst des Jahres 1886 machte Heinrich Hertz, der 29 jährige Professor für Physik an der Technischen Hochschule in Karlsruhe, in seinem Laboratorium eine folgenreiche Beobachtung. Bei Experimenten mit Drahtspulen, deren Wicklungen von einer… … Universal-Lexikon
hertz — [hə:ts US hə:rts] n plural hertz written abbreviation Hz [Date: 1800 1900; Origin: Heinrich Hertz (1857 94), German scientist who worked on energy waves] a unit for measuring the ↑frequency of ↑sound waves … Dictionary of contemporary English
Hertz — Hertz, n. [from the German physicist Heinrich Hertz.] a unit of frequency equal to one cycle per second; it is abbreviated Hz. It is commonly used to specify the frequency of radio waves, and also the clock frequencies in digital computers. For… … The Collaborative International Dictionary of English
HERTZ, GUSTAV — (1887–1975), German physicist and Nobel Prize winner, son of a Jewish father. Born in Hamburg, he became an assistant in the Physical Institute at Berlin in 1913. He was severely wounded in World War I, and subsequently worked at Eindhoven in… … Encyclopedia of Judaism
hertz — [ hɜrts ] (plural hertz) noun count a unit for measuring sound and radio waves … Usage of the words and phrases in modern English
Hertz,Heinrich Rudolf — Hertz (hûrts, hĕrts), Heinrich Rudolf. 1857 1894. German physicist who was the first to produce radio waves artificially. * * * … Universalium
Hertz , Heinrich Rudolf — (1857–1894) German physicist Hertz came from a prosperous and cultured Hamburg family. In 1875 he went to Frankfurt to gain practical experience in engineering and after a year of military service (1876–77) spent a year at the University of… … Scientists
Hertz — This article is about the unit of frequency. For the rental car company, see The Hertz Corporation. For other uses, see Hertz (disambiguation). MHz and MHZ redirect here. For other uses, see MHZ (disambiguation). Hz redirects here. For other uses … Wikipedia
hertz — (Hz) the SI unit of frequency, equal to one cycle per second. The hertz is used to measure the rates of events that happen periodically in a fixed and definite cycle; the becquerel, also equal to one event per second, is used to measure the… … Dictionary of units of measurement
Hertz — F/A/V 1. Unit for measuring frequency of d signal; formerly called cycles per second. 2. cycles per second of an electrical signal. WikiV The standard unit for measuring frequency. One hertz (abbreviated Hz) equals one cycle per second. It is… … Audio and video glossary
hertz — UK [hɜː(r)ts] / US [hɜrts] noun [countable] Word forms hertz : singular hertz plural hertz physics a unit for measuring the frequency of sound waves and radio waves … English dictionary
