Hertz

Dr Daniel J Bell et al.

Hertz (Hz) is the derived SI unit for frequency. One hertz represents one cycle per second, and thus in base SI units equates to one per second (1/s). In radiology, it is usually encountered in the context of ultrasound physics.

Terminology

As for all other eponymous units when the name is written out in full it is not capitalized, but its symbol is capitalized. Hertz is also the plural form; "hertzs" is incorrect.

History and etymology

The unit is named after Heinrich Rudolf Hertz (1857-1894) 2, a brilliant German physicist, remembered chiefly for his achievement in proving the existence of electromagnetic waves 1,2. Interestingly, in retrospect it is now the historical consensus that he suffered from granulomatosis with polyangiitis (Wegener granulomatosis), which explains his premature death at the age of only 36 years old 2.

Physics and imaging technology: ultrasound
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Article information

rID: 68971
Section: Physics
Tag: units
Synonyms or Alternate Spellings:
  • Hertz (Hz)

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