Circle Concepts Made Great : With Points For Class 6th,7th,8th,9th,10th [1]

1) A line segment with one end point at the center of a circle and the other on the circle is called a ‘radius’ of the circle.

2) All radii of a circle are equal.

3) A line segment passing through the center of a circle and having its end points on the circle is called a ‘diameter’ of the circle.

4) Diameter = 2 * ( radius ).

5) All the diameters of a circle meet at the center of the circle.

6) A point lies in the ‘interior of a circle’, on the ‘circle ‘ or in the ‘exterior of a circle’, if its distance from the center is less than, equal to or greater than the radius of the circle, respectively.

7) A line segment with its end points lying on a circle is called a ‘chord of the circle’.

8) The diameter is the longest chord of the circle.

9) A line passing through a circle and intersecting the circle at two points is called a ‘secant’ of the circle.

10) The interior of a circle together with the circle itself is called the ‘circular region’.

11) The end points of the diameter of a circle divide the circle into two equal parts ; each part is called a semicircle.

12) A diameter of a circle divides the circular region into two equal parts ; each part is called a ‘semicircular region’.

13) The perimeter of a circle is called its ‘circumference’.

14) Any part of a circle is called an ‘arc’ of the circle.

15) A chord of a circle divides the circular region into two parts ; each part is called a ‘segment’.

16) The segment containing the center of the circle is called the major segment, and the other part is called the minor segment of the circle.