Zepto-

Zepto (unit symbol z) is a unit prefix in the metric system denoting a factor of 10−21 or 0.000000000000000000001.

Adopted in 1991, it comes from the Latin septem, meaning "seven", since it is equal to 1000−7.

Examples of its use:

Prefix Base 1000 Base 10 Decimal English word Adoption[nb 1]
Name Symbol Short scale Long scale
yotta Y  10008  1024 1000000000000000000000000  septillion  quadrillion 1991
zetta Z  10007  1021 1000000000000000000000  sextillion  trilliard 1991
exa E  10006  1018 1000000000000000000  quintillion  trillion 1975
peta P  10005  1015 1000000000000000  quadrillion  billiard 1975
tera T  10004  1012 1000000000000  trillion  billion 1960
giga G  10003  109 1000000000  billion  milliard 1960
mega M  10002  106 1000000  million 1873
kilo k  10001  103 1000  thousand 1795
hecto h  10002/3  102 100  hundred 1795
deca da  10001/3  101 10  ten 1795
 10000  100 1  one –
deci d  1000−1/3  10−1 0.1  tenth 1795
centi c  1000−2/3   10−2 0.01  hundredth 1795
milli m  1000−1  10−3 0.001  thousandth 1795
micro µ  1000−2  10−6 0.000001  millionth 1873
nano n  1000−3  10−9 0.000000001  billionth  milliardth 1960
pico p  1000−4  10−12 0.000000000001  trillionth  billionth 1960
femto f  1000−5  10−15 0.000000000000001  quadrillionth  billiardth 1964
atto a  1000−6  10−18 0.000000000000000001  quintillionth  trillionth 1964
zepto z  1000−7  10−21 0.000000000000000000001  sextillionth  trilliardth 1991
yocto y  1000−8  10−24  0.000000000000000000000001  septillionth  quadrillionth 1991
  1. ↑ Prefixes adopted before 1960 already existed before SI. 1873 was the introduction of the CGS system.

References

  1. ↑ Professor John Dell, Slide 2: https://www.engineersaustralia.org.au/sites/default/files/shado/Learned%20Groups/Colleges/Mechanical%20College/WA%20Branch/Mechanical%20Engineering%20Gone%20Small%20(Presentation%20with%20Audio).pdf
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.