All About Circles that a Beginner has got to know! Includes all the parts of a circle and basic relations between arcs, segments, sectors, diameters and radii.

2. A project by Afrah Aamer

3.  Circles in Our Daily life
 Circles in Music
 Circles
 Circumference
 Circular Region
 Radius
 Diameter
 Chord
 Arc
 Semi-Circle
 Circle’s Parts

4. Bicycle Indian FlagCoin
CIRCLES

5. Bass Drum Snare DrumBingo Drum
CIRCLES

6. OCentre A circle
 A circle is a closed curve consisting of all points in
a plane which are at the same distance(equidistant)
from a fixed point inside it.
 This fixed point (equidistant) inside a circle is called
center.
 A circle has one and only one centre.

7. O
A
The distance around a circle is called its circumference.

8. 2. Interior of a Circle
O
1. The circle
3. Exterior of a Circle
A
B
A circle divides a plane into three parts- the circle, Interior and the Exterior.

9. A
O
 A line segment that joins any point on the circle
to its center is called a radius.
 Radii (plural of radius) of a circle are equal in
length
 Infinite number of radius can be drawn in a
circle.
M
N
L

10. DiameterAB
A
O
B
A line segment that joins any two points on the circle and passes through its center is called a diameter.

11. O
B
Q
P
A
N
M
 As the radii of a circle are equal in length, its
diameters too are equal in length.
 Infinite number of diameters can be drawn
in a circle.

12. Radius OM
M
O
N
Radius ON
Diameter MN
 Radius OM = Radius ON
 Diameter MN = Radius OM + Radius ON
 The length of the diameter of a circle is
twice the length of its radius.

13. B
A
A is a point on the
circle
B is also a point on
the circle
A line segment that joins any two points on the circle is called a chord.

14. O
Chord CD
C D
M
N
K
L
Diameter CD
Diameter is also a chord of the circle.

15. Diameter CD
C D
M N
Chord MN
C D
M N
Chord KL
LK
The diameter is the longest chord.

16. An arc is the distance between any two points on the circumference of a circle.
O
Centre
K L

17. Half of a circle is called a semicircle.
Centre
O
Diameter
D E
S
A semicircle is also an arc of the circle.
R
Arc DSE
Semicircle DRE
Semicircle DSE
Arc DRE

18. A chord divides the circular region into 2 parts, each of which is
called a segment of the circle.
Centre
O
D E
Chord DE
Minor segment of a circle
Major segment of a circle
S
R

19. S
Centre
M
P
ED
Q
G
O
F
Diameter DE