Calculations at a circular sector. A circular sector is formed by a circle and an angle originating at its center.
Enter radius and angle and choose the number of decimal places. Then click Calculate. Please enter angles in degrees, here you can convert angle units.
Formulas:
l = 2 * r * π * Θ / 360°
p = l + 2 * r
A = r² * π * Θ / 360°
pi:
π = 3.141592653589793...
Radius, arc length and perimeter have the same unit (e.g. meter), the area has this unit squared (e.g. square meter).
In geometry, a sector of a two-dimensional shape is a section that starts from the center of a shape and from which two straight lines run outwards. The area between these straight lines is the sector. The remaining area of the original shape without this section is also called a sector. A circular sector is made up of a circular segment and an isosceles triangle placed at the base, the tip of which is at the center of the circle. A circular sector is axially symmetrical to the bisector of this tip. Circular sectors are used, for example, in pie charts to illustrate the size of parts. Hereby, often a whole circle is broken down into individual sectors or "pie slices".
Calculating the values of a circular sector is simple. The arc length corresponds to the circumference of the circle multiplied with the proportion that the angle of the sector has of the full circle. The same applies to calculating the area. The circumference of a circular sector is the arc length plus the length of both legs of the isosceles triangle.
Special types of circular sectors are a quarter circle with an angle of 90 degrees and a semicircle with an angle of 180 degrees. Sectors can also be cut out of other two-dimensional shapes. For example, there is a annulus sector and an elliptical sector. The three-dimensional equivalent of a circular sector is, depending on interpretation, either a spherical sector or a cylindrical sector.