Circle
A circle is a particular shape of the objects. A circle is a type of closed shape. It is the set of all points in a plane that are at a given distance from a given point. So, it is the curve traced out by a point that moves in a plane in such a way so that its distance from the given point is constant.
Where,
r the radius of the circle.
d the diameter of the circle.
C circumference of the circle.
Diameter of the Circle
D = 2 × R
Circumference of the circle
C = 2 × π × R
Example:
Find the circumference of a circle whose radius is 10 cm.
Solution:
Circumference, C = 2πr
= 2 ×3.14×10
= 62.8 cm
Area of the circle:
A = π × R2
Example:
Find the area of a circle whose radius is 10 cm
Solution:
Area = 3.14 × 102
= 314 cm2