|an arrangement of five objects, as trees, in a square or rectangle, one at each corner and one in the middle.|
|a children's mummer's parade, as on the Fourth of July, with prizes for the best costumes.|
|Hertz (hɜːts, German hɛrts)|
|1.||Gustav (ˈɡʊstaf). 1887--1975, German atomic physicist. He provided evidence for the quantum theory by his research with Franck on the effects produced by bombarding atoms with electrons: they shared the Nobel prize for physics (1925)|
|2.||Heinrich Rudolph (ˈhainrɪç ˈruːdɔlf). 1857--94, German physicist. He was the first to produce electromagnetic waves artificially|
n. pl. hertz
A unit of frequency equal to 1 cycle per second.
|hertz (hûrts) Pronunciation Key
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The SI derived unit used to measure the frequency of vibrations and waves, such as sound waves and electromagnetic waves. One hertz is equal to one cycle per second. The hertz is named after German physicist Heinrich Hertz (1857-1894).
unit of frequency. The number of hertz (abbreviated Hz) equals the number of cycles per second. The frequency of any phenomenon with regular periodic variations can be expressed in hertz, but the term is used most frequently in connection with alternating electric currents, electromagnetic waves (light, radar, etc.), and sound. It is part of the International System of Units (SI), which is based on the metric system. The term hertz was proposed in the early 1920s by German scientists to honour the 19th-century German physicist Heinrich Hertz. The unit was adopted in October 1933 by a committee of the International Electrotechnical Commission and is in widespread use today, although it has not entirely replaced the expression "cycles per second."
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