Hertz

The hertz (symbol Hz) is the SI derived unit of frequency, which is expressed in terms of oscillations per second (s^-1, 1/s).

For example, red light has a frequency of about 4.6×10¹⁴ Hz. The unit is named in honor of the German physicist Heinrich Rudolf Hertz who made some important contributions to science in the field of electromagnetism.

Alternating current electric power is supplied at either 50 Hz or 60 Hz depending on the standard in the country. Power systems that have differing frequency can only be connected by using a HVDC link.

Multiples:

1 terahertz (THz) = 10¹² Hz = 1,000,000,000,000 Hz

1 gigahertz (GHz) = 10⁹ Hz = 1,000,000,000 Hz

1 megahertz (MHz) = 10⁶ Hz = 1,000,000 Hz

1 kilohertz (kHz) = 10³ Hz = 1,000 Hz

In older writings, the equivalent term cycle per second (cps) is seen.