 ### Circle With Sector and Segment labeled

Illustration of circle with sector and segment used to find area. ### Circle With Sector and Segment labeled

Illustration of partial circle with sector and segment used to find area. ### Sector of Circle

Illustration of a circle with a sector. "A sector of a circle is the space included between an arc and… ### Sector Of Circle

Illustration of a sector of a circle. A sector is the space between an arc and two radii drawn to the… ### Sector Of A Hollow Circle

Illustration of a sector of a hollow circle. A sector is the space between an arc and two radii drawn… ### Sectors of Circle

Illustration of a circle with 6 equal sectors. ### Circle with Segment, Semicircle, Sector, Quadrant, and Central Angle

Illustrations of a circle with segment, semicircle, sector, quadrant, and central angles drawn. ### Condensing Light

"Fixed Conensing Light for a Single Sector, 1850.—The holophote Light pLp throws its whole light… ### Finger system

"Used with indistinct or invisible targets and to define sectors." — Moss, 1914 ### Triangles and Sectors in Quadrant I

Illustration of an angle &alpha with the vertex at the center, O, of a circle with radius OB. AC and… ### Sector

The sector is a hinged rule with scales used for various mathematical calculations. ### Sector

"In geometry: (a) A plane figure inclosed between the arc of a circle, ellipse, or other central curve… ### Circle Sector

An illustration showing a circle sector with radius r, center/central angle v, and length of circle… ### Circle Sector

An illustration showing a circle sector with center/central angle v and polygon angle w. ### Circle Sector

An illustration showing a circle sector with height of segment h and radius r. ### Sphere With Sectors and Arcs

Diagram of a sphere with sectors and arcs drawn. ### Sphere With Sectors and Arcs

Illustration of a sphere with sectors and arcs. ### Napier's Right Spherical Triangle

Illustration of a right spherical triangle and the five circular parts placed in the sectors of a circle… ### Relationships In A Spherical Triangle

Illustration used, with the law of sines, to find the relation between two sides of a spherical triangle… ### Relationships In A Spherical Triangle

Illustration used, with the law of cosines, to find the relation between the three sides and an angle… ### Relationships In A Spherical Triangle

Illustration used to extend the law of cosines when finding the relation between the three sides and… ### Relationships In A Spherical Triangle

Illustration used to extend the law of cosines when finding the relation between the three sides and… ### Right Spherical Triangle

Illustration of a right spherical triangle with a and b the sides, and α and β the angles… ### Superimposed Symmetrical Spherical Triangles

Diagram showing 2 superimposed symmetrical spherical triangles. ### Symmetrical Spherical Triangles

Diagram showing 2 symmetrical spherical triangles. ### Circle Inscribed In A Triangle

An illustration showing a circle with sectors D and E inscribed in a triangle with angles, A, B, and… ### Spherical Triangle

Diagram showing a spherical triangle. ### Spherical Triangle

Diagram showing a spherical triangle constructed by the intersection of polar arcs. ### Spherical Triangle

Diagram showing a spherical triangle constructed by the intersection of polar arcs. ### Spherical Triangle

Diagram showing a spherical triangle constructed by the intersection of polar arcs. ### Two Symmetrical Spherical Triangles

Diagram showing a 2 symmetrical spherical triangles.