Learn Class 9 Math - Circles

The term circle refers to a closed figure that consists of diameter and radius. The diameter is the full line that passed from the circle. At the same time, the radius is half of the diameter. Many components of circles are present that make the complete circle. The area of the circle is πr2.

Interior and exterior of the circle

There are two components, i.e., the interior and exterior of a circle. These are the two different components that make a circle.

• The interior of a circle is the part of a circle. Further that includes the distance of the circle is less than the radius of a circle.
• The exterior of a circle is the part of a circle. Further, that includes the distance of the circle is more than the radius of a circle.

Components of a circle

1. Sector:

• The sector of a circle is considered an area covered by the two radii and an arc.
• These two things, i.e., arc and radii, pass from the circle's centre.
• The sector can be major or minor.

2. Arc:

• The curve joins the two points.
• The arc can be of two types, i.e., major and minor.

3. Circumference:

• The circumference of a circle is the perimeter of a circle.

Learning Videos for 9th Grade Math - Circles