Shake (unit): Difference between revisions
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Quuxplusone (talk | contribs) With the misinformation corrected, this bit of trivia might not belong here at all, I dunno |
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Like many informal units having to do with nuclear physics, it arose from [[top secret]] operations of the [[Manhattan Project]] during [[World War II]]. The word "shake" was taken from the [[idiomatic expression]] [[wikt:in two shakes of a lamb's tail|"in two shakes of a lamb's tail"]], which indicates a very short time interval. |
Like many informal units having to do with nuclear physics, it arose from [[top secret]] operations of the [[Manhattan Project]] during [[World War II]]. The word "shake" was taken from the [[idiomatic expression]] [[wikt:in two shakes of a lamb's tail|"in two shakes of a lamb's tail"]], which indicates a very short time interval. |
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The phrase "a couple of shakes," in reference to the measurement of time, may have been popularized by [[Richard Barham]]'s ''[[Ingoldsby Legends]]'' (1840);<ref name="Barham1840"/> however, the phrase was already part of vernacular language long before that.<ref name="Bruce2011"/> |
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==Nuclear physics== |
==Nuclear physics== |
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== References == |
== References == |
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<references> |
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{{reflist}} |
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<ref name="Barham1840">{{cite book |author=[[Richard Harris Barham]] |year=1840 |chapter=The Babes in the Wood |title=The Ingoldsby Legends |page=191 |url=https://archive.org/details/ingoldsbylegend02ingogoog/page/n212 |quote=I'll be back in a couple of shakes.}} Also on page 212 ("A Row in an Omnibus") "in a brace of shakes" and on page 247 ("The Lay of St. Alois") "in a couple of shakes." But the phrase appeared in print before Barham; see for example {{cite book |title=Transatlantic Sketches |author=[[James Edward Alexander]] |year=1833 |page=284 |url=https://archive.org/details/transatlanticsk00unkngoog/page/n320}}</ref> |
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| ⚫ | <ref name="Bruce2011">{{cite web |author=Elyse Bruce |title=Two shakes of a lamb's tail |year=2011 |website=idiomation.wordpress.com |url=http://idiomation.wordpress.com/2011/01/28/two-shakes-of-a-lambs-tail/ |access-date=2012-06-28 |url-status=live |archive-url=https://web.archive.org/web/20120502071023/http://idiomation.wordpress.com/2011/01/28/two-shakes-of-a-lambs-tail/ |archive-date=2012-05-02}}</ref> |
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</references> |
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{{Time measurement and standards}} |
{{Time measurement and standards}} |
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Latest revision as of 17:38, 28 July 2024
A shake is an informal metric unit of time equal to 10 nanoseconds, or 10−8 seconds.[1] It was originally coined for use in nuclear physics, helping to conveniently express the timing of various events in a nuclear reaction.
Etymology
[edit]Like many informal units having to do with nuclear physics, it arose from top secret operations of the Manhattan Project during World War II. The word "shake" was taken from the idiomatic expression "in two shakes of a lamb's tail", which indicates a very short time interval.
The phrase "a couple of shakes," in reference to the measurement of time, may have been popularized by Richard Barham's Ingoldsby Legends (1840);[2] however, the phrase was already part of vernacular language long before that.[3]
Nuclear physics
[edit]For nuclear-bomb designers, the term was a convenient name for the short interval, rounded to 10 nanoseconds, which was frequently seen in their measurements and calculations: The typical time required for one step in a chain reaction (i.e. the typical time for each neutron to cause a fission event, which releases more neutrons) is of the order of 1 shake, and a chain reaction is typically complete by 50 to 100 shakes.[4]
Integrated circuitry
[edit]Shakes are also applicable to circuits. Since signal progression in IC chips is very rapid, on the order of nanoseconds, a shake is a good measure of how quickly a signal can progress through an integrated circuit (IC).
See also
[edit]- ‘Barn’ a companion unit of cross-sectional area created by the same people, for the same general purposes, at the same time (the measured value of nuclear-reaction cross section was larger than expected, hence deemed “as big as a barn”).
- List of humorous units of measurement
References
[edit]- ^ Rowlett, Russ (ed.). "[Letter] S". How many? A dictionary of units of measurement. Chapel Hill, NC: University of North Carolina. Archived from the original on 2007-06-29.
- ^ Richard Harris Barham (1840). "The Babes in the Wood". The Ingoldsby Legends. p. 191.
I'll be back in a couple of shakes.
Also on page 212 ("A Row in an Omnibus") "in a brace of shakes" and on page 247 ("The Lay of St. Alois") "in a couple of shakes." But the phrase appeared in print before Barham; see for example James Edward Alexander (1833). Transatlantic Sketches. p. 284. - ^ Elyse Bruce (2011). "Two shakes of a lamb's tail". idiomation.wordpress.com. Archived from the original on 2012-05-02. Retrieved 2012-06-28.
- ^ Cochran, Thomas B. (10 April 1994). "Hydronuclear Testing or a Comprehensive Test Ban?" (PDF). Washington, DC: Natural Resources Defense Council. p. 4. Archived from the original (PDF) on 2008-12-06.
The period, 10−8 seconds, turns out to be a convenient unit of time, and it was defined during the Manhattan Project as one 'shake'.
