Exa-
 | Look up exa- in Wiktionary, the free dictionary. |
Exa is a decimal unit prefix in the metric system denoting 1018 or 1000000000000000000. It was added as an SI prefix to the International System of Units (SI) in 1975,[1] and has the unit symbol E.
Exa comes from the Ancient Greek ἕξ héx, used as a prefix ἑξά- hexá-, meaning six (like hexa-), because it is equal to 10006.
Examples:
- The total storage needed by Google Mail as of April 2012, ignoring backups and compression, is more than an exabyte (10,240 megabytes of storage per user multiplied by an estimated 260 million users).
- 1 EeV = 1018electronvolts = 0.1602 joule
United States electric energy consumption is about 15 exajoule per year.- 1 exasecond is approximately 32 billion years
1 exametre is approximately 110 light years
- 0.43 Es ≈ the approximate age of the Universe
- 1.6 Em—172 ± 12.5 light years—Diameter of Omega Centauri (one of the largest known globular clusters, perhaps containing over a million stars)[2][3]
- 23.6 exahashes/s is the calculation rate of the Bitcoin network ≈ 23600000000000000000 hashes per second (Mar 2018)[4]
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^ Prefixes adopted before 1960 already existed before SI. 1873 was the introduction of the CGS system.
See also
- Exametre
- Exabyte
- Exasecond
- Orders of magnitude (numbers)
- Metric prefix
- Binary prefix
References
^ "Resolution 10 of the 15th meeting of the CGPM (1975)". International Bureau of Weights and Measures. Retrieved 2012-04-18..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"""""""'""'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}
^ distance × sin( diameter_angle ), using distance of 5 kpc (15.8 ± 1.1 kly) and angle 36.3', = 172 ± 12.5 ly.
^ van de Ven, G.; van den Bosch, R. C. E.; Verolme, E. K.; de Zeeuw, P. T. (January II 2006). "The dynamical distance and intrinsic structure of the globular cluster ω Centauri". Astronomy and Astrophysics. 445 (2): 513–543. arXiv:astro-ph/0509228. Bibcode:2006A&A...445..513V. doi:10.1051/0004-6361:20053061.best-fit dynamical distance D=4.8±0.3 kpc ... consistent with the canonical value 5.0±0.2 kpc obtained by photometric methods
Check date values in:|date=(help)CS1 maint: Multiple names: authors list (link)
^ "Bitcoinity.org". data.bitcoinity.org. Retrieved 2017-12-06.
International Bureau of Weights and Measures (2006), The International System of Units (SI) (PDF) (8th ed.), ISBN 92-822-2213-6, archived (PDF) from the original on 2017-08-14
External links
| Look up exa- in Wiktionary, the free dictionary. |
- BIPM website
- Exa Corporation
- Exa Proxy Test
