Straight Angle

Pronunciation: /streɪt ˈæŋ gəl/ ?

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Angles are divided into four classes according to their measure. A straight angle is an angle that measures 1/2 of a full circle.[1]

Classes of Angles
Degree MeasureRadian MeasureClass Name
α<90°α<π/2 rad. Acute angle
α=90°α=π/2 rad. Right angle
90°<α<180°π/2<α<π rad. Obtuse angle
α=180°α=π rad. Straight angle
180<α<360°π<α<2π rad. Reflex angle
α=360°α=2π rad. Full angle
Table 1: Classes of angles

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References

  1. Keller, Samuel Smith. Mathematics for Engineering Students, Plane and Solid Geometry, pg 2. D. Van Nostrand Company, 1908. (Accessed: 2010-01-02). http://www.archive.org/stream/mathengineer00kellrich#page/2/mode/1up/search/straight.
  2. Hilbert, David. The Foundations of Geometry, pp 18-19. Townsend, E. J., Ph. D.. The Open Court Publishing Company, 1950. (Accessed: 2009-12-21). http://www.gutenberg.org/files/17384/17384-pdf.pdf.

Cite this article as:


Straight Angle. 2010-01-01. All Math Words Encyclopedia. Life is a Story Problem LLC. http://www.allmathwords.org/en/s/straightangle.html.

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Revision History


2010-01-01: Added "References" (McAdams, David.)
2009-12-14: Initial version (McAdams, David.)

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