#Area of a circle calculator how to#

#Area of a circle calculator how to#

There are different tools for measuring angles, depending on your particular situation. How to calculate Area of quadrant of Circle using this online calculator To use this online calculator for Area of quadrant of Circle, enter Radius (r) and hit the calculate button. This online calculator will find the area, circumference and radii of an annulus. If the sector is a quadrant, then the angle is 90°. A 2 area of circle of r 2, area within inner circle A 0 shaded area, outer area minus inner area A 0 A 1 - A 2 pi 3.1415926535898 square root Calculator Use. You need to measure or know two things: the sector's radius and its angle. Instead, you may be given the diameter of a circle. Some problems or situations will not provide you with the radius. Method 2 Calculating Area from the Diameter 1 Measure or record the diameter. π is, of course, the mathematical constant equal to about 3.14159. For the sample circle with a radius of 6 cm, the area will be either 36 cm 2 or 113.04 cm 2. The radius can be expressed as either degrees or radians, with our area of a sector calculator accepting only degrees for now (let us know if it would help you if it supported radians as well).

Measuring the diameter is easier in many practical situations, so another convenient way to write the formula is (angle / 360) x π x (diameter / 2) 2. The figure below illustrates the measurement:Īs you can easily see, it is quite similar to that of a circle, but modified to account for the fact that a sector is just a part of a circle. The formula for the area of a sector is (angle / 360) x π x radius 2. All of the area within the boundary of the circle, expressed as a square of the unit of measurement (square mm, square feet, etc.).