OK. US mpg =/= UK CA mpg 抄来概念学习学习

维基百科的加仑定义

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, and is equal to exactly 3.785411784 litres or about 0.133680555 cubic feet. This is the most common definition of a gallon in the United States. The U.S. fluid ounce is defined as 1⁄128 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 4.40488377086 litres. 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.

The imperial (UK) gallon was legally defined as 4.54609 litres. 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 1⁄160 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. In 2005 a major step in metrication i.e. kilometres and litres, was taken in Ireland, only excluding draught beer.



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.

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 advertised in litres per 100 km, or km per litre). It continues to be used as a unit of measure for fuel in Antigua and Barbuda, Belize, Burma (Myanmar), Cayman Islands, Grenada, 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.

所有跟帖： 

• right -xxhhwxc- ♂ (47 bytes) () 07/27/2010 postreply 07:45:28

• 国际标准万岁。 -booloolood -booloolood- ♂ (0 bytes) () 07/27/2010 postreply 08:22:05

• 简单点：1美加仑=3.785412升；而1英加仑=4.546087升 -Kaolin007- ♂ (43 bytes) () 07/27/2010 postreply 10:08:44