- See also the car rental company, The Hertz Corporation, and Hertz (disambiguation).
The hertz (symbol: Hz) is the SI unit of frequency. It is named in honour of the German physicist Heinrich Rudolf Hertz who made important scientific contributions to electromagnetism.
Definition
One hertz is defined as one cycle per second.
- 1 Hz = 1 s−1
SI multiples
| Multiple |
Name |
Symbol |
|
Multiple |
Name |
Symbol |
| 100 |
hertz |
Hz |
|
|
|
|
| 101 |
decahertz |
daHz |
|
10–1 |
decihertz |
dHz |
| 102 |
hectohertz |
hHz |
|
10–2 |
centihertz |
cHz |
| 103 |
kilohertz |
kHz |
|
10–3 |
millihertz |
mHz |
| 106 |
megahertz |
MHz |
|
10–6 |
microhertz |
µHz |
| 109 |
gigahertz |
GHz |
|
10–9 |
nanohertz |
nHz |
| 1012 |
terahertz |
THz |
|
10–12 |
picohertz |
pHz |
| 1015 |
petahertz |
PHz |
|
10–15 |
femtohertz |
fHz |
| 1018 |
exahertz |
EHz |
|
10–18 |
attohertz |
aHz |
| 1021 |
zettahertz |
ZHz |
|
10–21 |
zeptohertz |
zHz |
| 1024 |
yottahertz |
YHz |
|
10–24 |
yoctohertz |
yHz |
Explanation
One hertz simply means "one per second" (1 / s); 100 Hz means "one hundred per second", and so on. The unit may be applied to any periodic event – for example, a clock might be said to tick at 1 Hz, or a human heart might be said to beat at 1.2 Hz. Frequency of random events, such as radioactive decays, is expressed in becquerels.
The name hertz was adopted by the CGPM (Conférence générale des poids et mesures) in 1960, replacing the previous name for the unit, cycles per second (cps), along with its related multiples, primarily kilocycles (kc) and megacycles (mc). Hertz largely replaced cycles in common use by 1970.
See also
|
