5. A circle can be drawn with the help of a circular object.
For example: A circle drawn with the help of a coin.
A circle is a closed curve in a plane.
6. This fixed point (equidistant)
inside a circle is called
centre.
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.
OCentre
A circle
A circle has one and only
one centre.
7. Radius
A line segment that joins any point on the circle to its centre
is called a radius.
M
A point on the circle
CentreO
(Contd…)
8. Radii ( plural of radius) of a circle are equal in length.
Infinite number of radius can be drawn in a circle.
R
adius
Centre
K
O
L
M
N
(Contd…)
9. Diameter AB
A line segment that joins any two points on the circle and
passes through its centre is called a diameter.
A
B
A circle
O Centre
(Contd…)
10. A circle
O
M
Infinite number of diameters can be drawn in a circle.
As the radii of a circle are equal in length, its diameters too
B
Q
(Contd…)
Centre
P
A
N
11. The length of the diameter of a circle is twice the length of its
radius.
Radius OM
Centre
M
O
N
Radius ON
Diameter MN
Diameter MN = Radius OM + Radius ON
Radius OM = Radius ON
(Contd…)
12. A line segment that joins any two points on the circle is
called a chord.
O
B
A
A is a point on the
circle
B is another point
on the circle
A line segment that joins
point A and B
Chord
13. Diameter is also a chord of the circle.
O
Chord CD
C D
M
N
K
L
Chord MN
Chord KL
(Contd…)
Diameter CD
14. The diameter is the longest chord.
O
Diameter CD
C D
M N
Chord MN
(Contd…)
C D
M N
Chord KL
LK
15. L
K
M N
Chord MN
O Centre
Infinite number of chords can be drawn in a circle.
Chord KL
Chord
GH
G
H
18. K
C
O
Centre
It is a line that intersects the circle at exactly one
point on the circle. This point is called Point of
Tangency.
C
Point of
Tangency
19. O
Centre
An arc is the distance between any two points on the
circumference of a circle.
K L
(Contd…)
20. O
Centre
LK
An arc is named by three points, of which two are the end
points of the arc and the third one lies in between them.
X
Naming an arc
(Contd…)
Arc KXL
21. O
Centre
LK
X
Y
An arc divides the circle into two parts: the smaller arc is
called the minor arc, the larger one is called the major arc.
Minor Arc KXL
Major Arc KYL
(Contd…)
23. 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
(Contd…)
Semicircle DSE
Arc DRE
32. 1. the distance between any
two points on the
circumference of a circle.
2. A line segment that joins
any two points on a circle.
3..The line segment that joins
any two points on the
circle and passes through
its center.
4. Line segment that joins any
point on the circle to its
centre .
5. Line that intersects the
circle at any two point on
the circle.
6. line that intersects the circle
at exactly one point on the
circle
23 4
5
6
1
Direction: Fill in the box
the answers of its
corresponding statements
shown on the right.
Hint: The last letter of the
answer will be the first
letter of next answer.
33. Across:
1. the distance between any
two points on the
circumference of a circle.
2. A line segment that joins
any two points on a circle.
3..The line segment that joins
any two points on the
circle and passes through
its center.
4. Line segment that joins any
point on the circle to its
centre .
5. Line that intersects the
circle at any two point on
the circle.
6. line that intersects the circle
at exactly one point on the
circle
CHORDIA
M
E
T
E R A D I U S
E
C
ANTANGENT
R
A
Direction: Fill in the box
the answers of its
corresponding statements
shown on the right.
Hint: The last letter of the
answer will be the first
letter of next answer.
