User:Milton Beychok/Sandbox: Difference between revisions

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A '''gallon''' is a measure of [[volume]] of approximately four [[litre]]s in the United States, and approximately five [[litre]]s in the United Kingdom. Historically it has had many different definitions, but there are three definitions in current use.  These are the [[U.S. liquid gallon]] (≈&nbsp;3.78&nbsp;L) and the lesser used [[U.S. dry gallon]] (≈&nbsp;4.4&nbsp;L) which are in use in the [[United States]], and the [[Imperial (UK) gallon]] (≈&nbsp;4.5&nbsp;L) which is in unofficial use within the [[United Kingdom]] and [[Ireland]] and is in semi-official use within [[Canada]] (See [[Canadian units]]).<ref>{{cite web|url=http://laws.justice.gc.ca/en/showdoc/cs/W-6/sc:2//en#anchorsc:2|title=Weights and Measures Act: Canadian units of measure|publisher=Department of Justice|accessdate=2007-11-14}}</ref>  The gallon, be it the Imperial or U.S. gallon, is sometimes found in other [[English language|English]]-speaking countries.
The '''gallon''' (abbrevuation: '''gal''') is a non-[[SI]] measurement unit of [[volume]] used in the [[U.S. customary units|U.S. customary]] and the [[Imperial units|Imperial]] systems of measurement. Historically it has had many different definitions, but there are three definitions in current use.  These are the '''''U.S. liquid gallon''''' and the '''''U.S. dry gallon''''' which are used in the [[United States]] and the [[Imperial gallon]] which is in unofficial use within the [[United Kingdom]] and [[Ireland]] and in semi-official use within [[Canada]].<ref>{{cite web|url=http://laws.justice.gc.ca/en/showdoc/cs/W-6/sc:2//en#anchorsc:2|title=Weights and Measures Act: Canadian units of measure|publisher=Department of Justice|accessdate=2007-11-14}}</ref>  The gallon, be it the U.S. or Imperial gallon, is sometimes used in other [[English language|English]]-speaking countries as well.


==Definitions==
==Definitions==
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The gallons in current use are subdivided into eight [[pint]]s or four [[quart]]s. [[Pint]]s are further subdivided into [[fluid ounce]]s and liquid gallons are also subdivided into 32 [[gill (unit)|gills]], i.e. a quarter of a pint. The sub-units of [[pint]] and [[fluid ounce]], despite having the same name in both Imperial and U.S. units, differ in volume and are therefore not interchangeable. The principal difference is that the Imperial [[pint]] contains 20 Imperial [[fluid ounce]]s, whereas the U.S. [[pint]] contains 16 U.S. [[fluid ounces]]. A U.S. [[fluid ounce]] is approximately 4% bigger than an Imperial [[fluid ounce]] and therefore they are often used interchangeably, whereas U.S. and Imperial pints and gallons are sufficiently different that they should not be used interchangeably, although they often are.
The gallons in current use are subdivided into eight [[pint]]s or four [[quart]]s. [[Pint]]s are further subdivided into [[fluid ounce]]s and liquid gallons are also subdivided into 32 [[gill (unit)|gills]], i.e. a quarter of a pint. The sub-units of [[pint]] and [[fluid ounce]], despite having the same name in both Imperial and U.S. units, differ in volume and are therefore not interchangeable. The principal difference is that the Imperial [[pint]] contains 20 Imperial [[fluid ounce]]s, whereas the U.S. [[pint]] contains 16 U.S. [[fluid ounces]]. A U.S. [[fluid ounce]] is approximately 4% bigger than an Imperial [[fluid ounce]] and therefore they are often used interchangeably, whereas U.S. and Imperial pints and gallons are sufficiently different that they should not be used interchangeably, although they often are.


Earlier in the 20th century, while Canada was still using the imperial gallon as its automotive fuel measurement, some U.S. citizens referred to the imperial fluid measure as a "five quart gallon", since an imperial gallon has a volume equal to 4.804 U.S. quarts.
==References==
{{reflist}}

Revision as of 18:11, 5 June 2010

The gallon (abbrevuation: gal) is a non-SI measurement unit of volume used in the U.S. customary and the Imperial systems of measurement. Historically it has had many different definitions, but there are three definitions in current use. These are the U.S. liquid gallon and the U.S. dry gallon which are used in the United States and the Imperial gallon which is in unofficial use within the United Kingdom and Ireland and in semi-official use within Canada.[1] The gallon, be it the U.S. or Imperial gallon, is sometimes used in other English-speaking countries as well.

Definitions

A one U.S. gallon gas can purchased near the U.S.-Canada border. It shows equivalences in Imperial gallons and litres.
  • The U.S. liquid gallon is legally defined as 231 cubic inches,[2] and is equal to exactly Template:Val or about Template:Val. This is the most common definition of a gallon in the United States. The U.S. fluid ounce is defined as Template:Frac of a U.S. gallon.
  • The U.S. dry gallon is one-eighth of a U.S. Winchester bushel of 2150.42 cubic inches, thus it is equal to exactly 268.8025 cubic inches or Template:Val. The U.S. dry gallon is less commonly used, and is not listed in the relevant statute, which jumps from the dry quart to the peck.[2]
  • The imperial (UK) gallon was legally defined as Template:Val. This definition is used in some Commonwealth countries and Ireland, and is based on the volume of 10 pounds of water at 62 °F. (A U.S. liquid gallon of water weighs about 8.33 pounds at the same temperature.) The imperial fluid ounce is defined as Template:Frac of an imperial gallon.

On 1 January 2000, it ceased to be a legal unit of measure within the United Kingdom for economic, health, safety or administrative purposes.[3] In 2005 a major step in metrication i.e. kilometres and litres, was taken in Ireland, only excluding draught beer.[4]

Worldwide usage of gallons

As of 2005 the U.S. liquid gallon continued to be used as a unit of measure for fuel in Colombia, Dominican Republic, Ecuador, El Salvador, Guatemala, Haiti, Honduras, Liberia, Nicaragua, Panama, Peru, and the United States.[5]

The Imperial gallon is used colloquially (and in advertising) in the United Kingdom and Canada for the fuel economy figures, in miles per gallon (elsewhere in Europe, the effective fuel consumption is often advertised in litres per 100 km, or km per litre). It continues to be used as a unit of measure for fuel[5] in Antigua and Barbuda,[6] Belize,[7][8] Burma (Myanmar),[9][10][11] Cayman Islands, Grenada,[12][13] Guyana, and Sierra Leone. The United Arab Emirates switched from Imperial gallons to litres on 1 January 2010.

The word has also been used as translation for several foreign units of the same magnitude.Template:Citation needed

Subdivisions

The gallons in current use are subdivided into eight pints or four quarts. Pints are further subdivided into fluid ounces and liquid gallons are also subdivided into 32 gills, i.e. a quarter of a pint. The sub-units of pint and fluid ounce, despite having the same name in both Imperial and U.S. units, differ in volume and are therefore not interchangeable. The principal difference is that the Imperial pint contains 20 Imperial fluid ounces, whereas the U.S. pint contains 16 U.S. fluid ounces. A U.S. fluid ounce is approximately 4% bigger than an Imperial fluid ounce and therefore they are often used interchangeably, whereas U.S. and Imperial pints and gallons are sufficiently different that they should not be used interchangeably, although they often are.

References

  1. Weights and Measures Act: Canadian units of measure. Department of Justice. Retrieved on 2007-11-14.
  2. 2.0 2.1 Authorized tables, U.S. Code, Title 15, ch. 6, subchapter I, sec. 205, accessed 19 July 2008.
  3. The Units of Measurement Regulations 1995 (Article 4) (2000-09-20). Retrieved on 2009-01-28.
  4. Metric usage and metrication in other countries (2009-02-13). Retrieved on 2009-07-03.
  5. 5.0 5.1 FuelPrices2005 (see chapter 12.2: Conversion units) (pdf) 96. German Technical Cooperation. Retrieved on 2008-06-10.
  6. The High Commission Antigua and Barbuda. Retrieved on 2008-01-15.
  7. Belize Ministry of Finance::FAQ. Belize Ministry of Finance. Retrieved on 2008-01-15. “#Kerosene per US Gallon (per Imperial gallon)#Gasoline (Regular)(per Imperial Gallon)# Gasoline (Premium) (per Imperial Gallon)#Diesel (per Imperial Gallon)”
  8. Belize shopping. Retrieved on 2008-01-15. “Although the Belize $ is pegged at two for every US$, they use Imperial gallons rather than the smaller US gallons (0.83 of an Imperial) when dealing with gasoline. The cheapest grade of gasoline was US$4.69/Imperial gallon”
  9. Erlanger, Steven. 500 Are Detained in Burmese Capital, The New York Times, 1990-08-25. Retrieved on 2008-01-16. “... the Government cut the ration of subsidized gasoline from six to four imperial gallons a week”
  10. Win, Aye Aye (2007-08-22). Fuel Hike Protest Begins in Myanmar. Associated Press. Retrieved on 2008-01-16. “The government, which holds a monopoly on fuel sales and subsidizes them, raised prices of fuel from $1.16 to $2.33 per imperial gallon for diesel and to $1.94 for gasoline. A canister of natural gas containing 17 gallons was raised from 39 cents to $1.94.”
  11. Burma's Activists March against Fuel Price. HikeThe Irrawaddy News Magazine Online Edition Covering Burma (2007-08-20). Retrieved on 2008-01-16. “The government, which holds a monopoly on fuel sales and subsidizes them, raised prices of fuel from 1,500 kyats (US $1.16) to 3,000 kyats ($2.33) per imperial gallon for diesel and to 2,500 kyats ($1.94) for gasoline.”
  12. GRENADA VISITOR FORUM - Cost Of Living - Grocery Prices. Retrieved on 2008-01-15.
  13. The Government of Grenada - The Ministry of Agriculture. Retrieved on 2008-01-15. “he price of gasoline at the pumps was fixed at EC$7.50 per imperial gallon...”