Search results
Results from the WOW.Com Content Network
square chain (US Survey) sq ch ≡ 66 ft (US) × 66 ft (US) = 1 ⁄ 10 US survey acre ≈ 404.6873 m 2: square foot: sq ft ≡ 1 ft × 1 ft: ≡ 9.290 304 × 10 −2 m 2: square foot (US Survey) sq ft ≡ 1 ft (US) × 1 ft (US) ≈ 9.290 341 161 3275 × 10 −2 m 2: square inch: sq in ≡ 1 in × 1 in: ≡ 6.4516 × 10 −4 m 2: square ...
The foot (standard symbol: ft) [1] [2] is a unit of length in the British imperial and United States customary systems of measurement. The prime symbol, ′, is commonly used to represent the foot. [3] In both customary and imperial units, one foot comprises 12 inches, and one yard comprises three feet.
The United States and the Metric System (LC 1136) nist.gov Archive.org; The Metric System in the United States Archived June 11, 2017, at the Wayback Machine; A Metric America: A Decision Whose Time Has Come on nist.gov Archive.org; Metric Conversion Act of 1975 on nist.gov Archive.org; www.us-metric.org—U.S. Metric Association (mirror link)
These are the defining dimensions for NAD 27, but Clarke actually defined his 1866 spheroid as a = 20,926,062 British feet, b = 20,855,121 British feet. The conversion to meters uses Clarke's 1865 inch-meter ratio of 39.370432. The length of a foot or meter at the time could not practically be benchmarked to better than about 0.02 mm. [11]
These efforts are known as "High Accuracy Reference Network" (HARN) or "High Precision GPS Network" (HPGN). In addition, the basic unit of distance used is sometimes feet and sometimes meters. Thus a fully described coordinate system often looks something like: "Washington State Plane North, NAD83 HARN, US Survey feet".
United States customary units form a system of measurement units commonly used in the United States and most U.S. territories, [1] since being standardized and adopted in 1832. [2] The United States customary system developed from English units that were in use in the British Empire before the U.S. became an independent country.
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
In many measurement systems based on former English units, the link has remained fixed at 0.66 feet, therefore 0.22 yards or 7.92 inches; it is the absolute length of the yard that has varied. A rare remaining application of the link is in the service of some surveying in the United States, which relates to the definition of the survey foot.