List of strange units of measurement

Strange and whimsical units are sometimes used by scientists, especially physicists and mathematicians, and other technically-minded people such as engineers and programmers, as bits of dry humor combined with putative practical convenience.

FFF

While most countries have Le Système International d’Unités (SI), this seems to be one more reason to delve into the Furlong/Firkin/Fortnight system of units of measurement which draws its attraction from being conservative and off-beat at the same time.

FFF Base units

Additionally, the Fahrenheit is usually considered the unit of temperature in FFF.

FFF derived units

Furlong/fortnight

1 furlong/fortnight is very nearly 1 centimetre/minute (to within 1 part in 400). Besides having the meaning of "any obscure unit", furlongs per fortnight have also served frequently in the classroom as an example on how to reduce a units' fraction.

It is perhaps remotely notable that using the FFF system the speed of light may be expressed as being roughly 1.8 megafurlongs per microfortnight. [1] (http://www.uk-rec-sheds.org.uk/faq60.txt)

Microfortnight

One very convenient unit deduced from this set is the 1-millionth part of the fundamental time unit of FFF, which equals 1.2096 seconds, and is a typical example of computer nerd humour. As the story goes, "The VMS operating system has a lot of tuning parameters that you can set with the SYSGEN utility, and one of these is TIMEPROMPTWAIT, the time the system will wait for an operator to set the correct date and time at boot if it realizes that the current value is bogus. This time is specified in microfortnights."[2] (http://info.astrian.net/jargon/terms/m.html#microfortnight)

The joke is in having a rather large, obsolete unit (fortnight) combined with a fractional SI prefix (micro) to counteract that. The practical purpose is to discourage setting such parameters without some thought.

Other

Further development of derived units, like firkin furlongs per fortnight squared for force, has yet to happen.

Nanocentury

Another example which shows this principle is the nanocentury. Another derived time unit, reducing a rather large time span (century) by preceding it with a fractional prefix (nano). As Tom Duff at Bell Labs pointed out: "How many seconds are there in a year? If I tell you there are 3.155 × 10⁷, you won't even try to remember it. On the other hand, who could forget that, to within half a percent, π seconds is a nanocentury."[3] (http://ptah.jpaulson.net/wip/Quotes.txt)

One computer science professor used to characterize the standard length of his lectures (a little less than an hour) as a microcentury.[4] (http://info.astrian.net/jargon/terms/m.html#micro-)

Attoparsec

Another nonstandard unit of length is the attoparsec. It comes in disguise and even has a proper abbreviation, "apc". It is, however, rarely used in the real world.

Parsecs are used in astronomy to measure enormous interstellar distances; a parsec is approximately 3.26 light-years or 3.085×10¹⁶m. Combining it with the "atto" prefix yields attoparsec, a conveniently human-scaled unit of 3.085 centimeters (about 1-7/32 inches) that has no obvious practical use.

Interestingly, 1 attoparsec/microfortnight is nearly 1 inch/second (the actual figure is 1.0043 inch per second).

Seemeilen/Woche

A German counterpart is the Seemeilen pro Woche, German for nautical miles per week. 1 Sm/Woche equals about 3 mm/s, said to be the nominal value for a snail's pace.

(This is reasonable for the European garden snail, Helix aspersa, whose speed is dependent on the surface and ranges from 1.05 mm/s on a paper towel to 2.8 mm/s on Formica. As of 2004 the record speed in the World Snail Racing Championships (http://www.west-norfolk.gov.uk/westnorfolk/tourism.nsf/pages/WorldSna083042.html) in Congham, U.K., set in 1995, is 13 inches in 2 minutes = 5.5 mm/s; the Costa Rican mountain snail Velifera can travel 18"/minute = 7.62 mm/s.)

Nanoacre

A nanoacre is a unit (about 2 mm square) of real estate on a VLSI chip. "The term gets its giggle value from the fact that VLSI nanoacres have costs in the same range as real acres in Silicon Valley once one figures in design and fabrication-setup costs." (Source: The Jargon File (http://catb.org/~esr/jargon/html/N/nanoacre.html))

Smoot

The smoot is a unit of length, defined as the height of Oliver R. Smoot, former president of ISO. The unit is used to measure the length of the Harvard Bridge. Canonically, and originally, in 1958 when Smoot was a student at MIT, the bridge was measured using Mr Smoot himself as a ruler, turning him end over end for the 364.4-smoot length of the bridge.

Poronkusema

Poronkusema (literally: passing of water of reindeer) is a measurement of distance originating from Northern Finland. It is a distance travelled in a reindeer pulled sleigh, between two instances of reindeer passing water. This distance is 7.5–10 km.

Lawyer

Paleontologists measure food consumption by the Tyrannosaurus rex in lawyers, after the scene in the film Jurassic Park in which a lawyer is consumed in one bite.

Gillette

A unit described by Theodore Maiman as an early measure of Laser output power. The measure was simply the number of razor blades through which the laser could burn a hole. This measurement was especially convenient as the first Lasers were pulsed Ruby Lasers, making it otherwise difficult to measure the output power. Also, due to the relative uniformity of razor blades manufactured by The Gillette Company, it had some usefulness as a rough comparison.

Thus, scientists would brag about having a "4 Gillette" Laser versus their competitor's puny "2 Gillette" Laser. (For the record, Ted Maiman claims that the first laser was a "2 Gillette" Laser.)

Potrzebie

In the 1950s, Mad magazine published its own system of weights and measures. The basic unit of this system was the potrzebie, which equals the thickness of Mad issue 23, or 2.263348517438173216473 mm.

Library of Congress

The term Library of Congress (or LoC) is sometimes used as a unit of measurement when discussing large amounts of data. It refers to the US Library of Congress. One Library of Congress equals approximately 20 terabytes of uncompressed textual data.

Stone's throw

A stone's throw is a measure of distance that can be traced back to the Viking Age, that is used to this day as a very approximate measure. No accurate definition exists, although it is sometimes seen equalled to 25 fathoms (46 m). In most cases "bare et stenkast væk" (Danish, meaning: just one stones throw away) is taken to mean "quite nearby". Spitting distance is another similar measurement of closeness

SI-Imperial hybrids

There are reports of engineers realizing the comfort of base ten SI prefixes, combining them with Imperial or US customary units instead of making the full switch, for example the kiloyard (914.4 m).

The kilofoot is quite common in US telecommunication engineering, as significant distances in cable route planning are usually given in thousands of feet. Instruments like optical time domain reflectometers usually have an option to display results in kFt.

In the US, gramms per ounce is a common measure used in sports nutrition, for example to measure the density of carbohydrate in a beverage.

Metric

There are also some obscure units used within the metric system(s). The issue is basically, that with arbitrary units and prefixes you can express a common unit with an unfamiliar term.

• For instance, the French at first preferred the are, which is 100 m², as base unit for areas; the square metre (m²) becomes a centiare (ca). Only the base unit and hectare (ha) saw a wider use and are still in use in some countries.
• Some also used the stere (st) equalling a cubic metre (m³), so the litre (l), which is a cubic decimetre (dm³), becomes a millistere (mst). Motorcyclists are often confused, if the cubic capacity of their engines are given in millilitre (ml) instead of cubic centimetre (cm³); on the contrary the same property for cars is usually given in litres (l), not cubic decimetres (dm³). On the next level, the kilolitre (kl) could replace the cubic metre (m³).
• The Soviets and French for a short period in the 20th century used a variant of the metric system where the base unit of mass was the tonne, meaning that a kilogram was a millitonne (mt). Conversely, some companies are using the megagram (Mg), to avoid confusion with Imperial tons.
• In 1793, the French term "grave" was suggested as the base unit for the metric system. Due in no small part to the French Revolution, in 1795 the name "kilogram" [5] (http://www1.bipm.org/en/si/history-si/name_kg.html) was adopted instead. Now we have a base unit with a prefix, due to a historical quirk.
• A mil in Norway and Sweden is a distance of 10 kilometres. The term originates from a pre-metric mil (in earlier times rast) of slightly over 10 km, denoting a suitable distance between rests when walking. The metric mil was officially established in Sweden on 1 January 1889. For geographical distances the term is probably used more than the kilometre. It is also used commonly for measuring vehicle fuel consumption, litres per mil means litres consumed per 10 km [6] (). However, confusingly, the mil is also a little-used much smaller unit equal to one-thousandth of an inch.

See also: Mesures usuelles

Nelson's Column

The Nelson's Column is a measure of height equal to 61.5 m. Used principally by British newspapers or reference books, it is useful in measuring the size of buildings or, occasionally, mountains.

Wales/Belgium

The Wales is a unit of area equal to 20,779 km². Used in phrases such as "an the area of Wales" or "twice the area of Wales". Smaller areas are measured in "football pitches". Rather than referring to Wales, some journalists refer to "the area of Belgium". This terminology is often used when referring to the depletion of the Amazon rainforest or large icebergs (all of which, it seems, are approximate multiples of Wales's or Belgium's area in size). The Wales and the Belgium can be easily converted between the two: 1 Belgium = 1.47 Waleses; 1 Wales = 0.68 Belgiums.

Rhode Island/Texas/Alaska

In the United States, the areas of Rhode Island (1,545 mi²), Texas (268,601 mi²), and rarely Alaska (656,425 mi²) are used in a similar fashion. For instance, Antarctica's Larsen B ice-shelf was approximately the size of Rhode Island until it broke up in 2002. Due to the Rhode Island being a relatively small unit of measurement (and, perhaps, due to its area being 33% water), many comparisons to the size of Rhode Island are somewhat imprecise (http://www.quahog.org/factsfolklore/index.php?id=12).

Jiffy

In computing, the jiffy is the duration of one tick of the system timer interrupt. Typically, this time is 0.01 seconds, though in some earlier systems (such as the Commodore 8-bit machines) the jiffy was defined as 1/60 of a second, roughly equal to the vertical blanking interval on NTSC video hardware.

Helen

The amount of beauty that can launch one thousand ships. Usually used as the millihelen, the amount of beauty that can launch one ship.

Named after Helen of Troy, from the Iliad, inspired by Marlowe's line, "Was this the face that launched a thousand ships...?".

Johm

Named after Jomanda, a Dutch new age guru who alleged to be able to infuse water with positive energy (even when she was on TV and watchers would place a glass of water in front of their set). One johm is the amount of positive radiation that Jomanda can generate in one day. The average person supposedly has a far smaller capacity for creating positive radition, usually measured in microjohms.

Microbit

The Finnish computer magazine MikroBITTI once claimed to be named after the microbit, defined as one millionth of a value that can be either 0 or 1.

Pinkwater

A notional unit of comfortable seating size; it can be used to describe both the width of a seat, or the width of a seat which a person needs to be comfortable in. Named for writer and book reviewer Daniel Pinkwater, and was coined by 'Click and Clack', the hosts of the Car Talk radio show.

Winger, Shudder

Notional units of Squick. One Winger is equal to the amount of mental disturbance caused by viewing a typical Doug Winger drawing. Usually expressed in milliWingers (mWgr). Shudders are measured by how many milliseconds the victim shudders after being squicked.

Sydharb

A unit of volume used in Australia for water. One sydharb is the ammount of water in Sydney Harbour: approximately 500 gigalitres. [7] (http://www.awa.asn.au/Content/NavigationMenu/Information/UnitsofMeasurement.pdf) [8] (http://www.atse.org.au/index.php?sectionid=631)

See also

• Conversion of units

External links

• http://www.sizeofwales.co.uk - an interactive convertor to strange units

Categories: Units of measure | Physics lists