Hertz

/hə:ts/
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Definition
  1. Noun:
    • A unit of frequency: The hertz is the SI unit of frequency, defined as one cycle per second. It is used to measure periodic events, such as sound waves, electrical signals, and light waves.
Usage
  • The hertz is abbreviated as Hz. Multiples are common, such as kilohertz (kHz, 10³ Hz), megahertz (MHz, 10⁶ Hz), and gigahertz (GHz, 10⁹ Hz).
  • It is used in physics, electronics, acoustics, and computing to describe how often something repeats in one second.
Examples
  • Noun:
    • The standard pitch for musical tuning is A above middle C, which vibrates at 440 hertz.
    • This radio station broadcasts at a frequency of 98.5 megahertz (MHz).
    • A computer's processor speed might be 3.5 gigahertz (GHz).
Advanced Usage
  • "Hertz" as a proper noun: The unit is named in honor of the German physicist Heinrich Rudolf Hertz (1857–1894), who first conclusively proved the existence of electromagnetic waves.
  • Contextual Use: In technical contexts, "hertz" specifies the rate of oscillation, vibration, or clock cycles.
    • The human ear can typically hear sounds from 20 hertz to 20,000 hertz.
Variants and Related Words
  • Hertzian (adj): Pertaining to or discovered by Heinrich Hertz.
    • Hertzian waves are another term for radio waves.
  • Kilohertz (kHz): One thousand hertz.
  • Megahertz (MHz): One million hertz.
  • Gigahertz (GHz): One billion hertz.
Synonyms
  • Cycle per second (cps): An older, non-SI term equivalent to one hertz. "Hertz" is now the standard term.
Related Phrases and Compounds
  • Hertz (Hz): The standard symbol.
  • Hertzian dipole: A type of radio antenna.
  • Hertz contact stress: Stress in materials at the point of contact, based on the work of Heinrich Hertz.
Noun
  1. German physicist who with James Franck proved the existence of the stationary energy states postulated by Bohr (1887-1975)
  2. German physicist who was the first to produce electromagnetic waves artificially (1857-1894)
  3. the unit of frequency; one hertz has a periodic interval of one second