What is the formula for circles?
We use the circle formula to calculate the area, diameter, and circumference of a circle. The length between any point on the circle and its center is known as its radius.
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Formulas Related to Circles.
Diameter of a Circle D = 2 × r
Circumference of a Circle C = 2 × π × r
Area of a Circle A = π × r2.
What are the different types of circles?
Types of Circles
Concentric Circles. When two or more circles have the common centre, then these circles are called concentric circles. In the above figure, there are three circles inside one other. ...
Contact of Circles. When outer surface of two circles are touching, it is known as contact of circles. ...
Orthogonal Circles.