Issuu on Google+

Circumference of a Circle Formula Circumference of a Circle Formula In the above diagram, ‘O’ is the centre of the circle, the white line is its radius and the black outline is the perimeter or circumference of the circle. Notice that a circle partitions the area into which it lies in three divisions. The first one is the region inside the circle. The second part is the region that is outside the realm of the circle. The third is the circle itself. The length of this margin that defines the circle is called as its circumference. It is henceforth the perimeter or edge of the circle. In this article, we will discuss the Circumference of a Circle Equation. We can compute he circumference of a circle with the help of its diameter by means of the formula given underneath: Circumference = π * diameter, Or, Circumference = π * 2 * radius, The above two formulas always yield the same result and are considered to be alternatives of each other. Know More About Homework help Math.Tutorvista.com

Page No. :- 1/4


The value of the constant π can be taken as 22 / 7 or 3.142 approximately. Thus, we can calculate the circumference of a circle with the help of only one quantity i.e. radius. Let us solve some problems related to the Circumference of a Circle Equation. Example 1: A circular jogging track is found to have a radius of 21 m. circumference of the jogging track?

Obtain the

Solution: Here, radius, r = 21 m, Since, Circumference, C = π * 2 * r, Therefore, C = π * 2 * 21 = 22 * 2 * 21 / 7 = 132 m, Example 2: the circumference of a circular patch is 88 inches. Determine its radius and diameter? Solution: In this example, the circumference of circular patch, C = 88 inches, Since, Circumference, C = π * 2 * r, Therefore, 88 = π * 2 * r, => r = 88 / (2 * π), => r = 88 / (2 * 22 / 7), => r = 88 * 7 / (2 * 22) = 14 inches. Also, diameter = 2 * r, Therefore, the diameter of circular patch is 28 inches. Learn More :- Algebra

Math.Tutorvista.com

Page No. :- 2/4


Example 3: A table is circular in shape. Its circumference is (25π)". Calculate the diameter of the table? Solution: In this example, the circumference of table, C = 25 π”, Putting the values in the formula, we can write C = π * d, Thus, d = 25 π / π = 25“, In addition to the above mentioned conceptions, keep in mind that for a circle with center (s, t) and radius (r), we can write its equation in x – y plane as, (x - s) 2 + (y - t) 2 = r 2, If we are given only the coordinates of a point on the circle and that of the centre of the circle, we can calculate its radius by substituting values in the above formula and subsequently calculate its circumference.

Math.Tutorvista.com

Page No. :- 4/4


Thank You For Watching

Presentation


Circumference of a Circle Formula