Closed curves

Simple Closed Curves

Simple closed curves made of line segments

WHAT IS A CIRCLE ?WHAT IS A CIRCLE ?

A CIRCLE IS A LOCUS OF A POINT WHICH ARE EQUIDISTANT FROM

THE FIXED POINT

CONSTRUCTION OF A CIRCLECONSTRUCTION OF A CIRCLE

CIRCULAR SHAPED OBJECTS

Medal

CoinsClock

Plate

TubeKey hole

Ring

Top

APPLICATION

PATTERNS IN CIRCLES

TOOTHED WHEEL GRINDING WHEEL FAN

DESIGNED WHEEL

COLOUR WHEEL

PATTERN OF A CIRCLE

Did you know we can draw a number of chords to the circle?

Can you guess which is the

longest chord?O

A

B

CD

E

F

G

RADII OF THE CIRCLE

We can draw a number of radii to the circle. All the radii are of equal length.

A

C

DE

F

B

O

The length of the diameter is always twice the length of the radius.

FIND ME WITH THE GIVEN CLUES IN THE LETTER MAZELOOK VERTICALLY HORIZONTALLY AND DIAGONALLY

• I measure half of the diameter . What is the name given to me?

• I am the distance around the circle. What am I called?

• I lie in the middle of the circle . Who am I?

• I pass through the centre and touch two ends of the circumference. What is my name?

• I am a line segment and my end points lie on the circle. Can you guess the name given to me?

A B C D E F G H I J R L M

C I R C U M F E R E N C E

M N R E O P Q R T S T H U

V W D N X Y Z E A B C O D

E F I T G H M I J K L R M

N O U R P A Q R S T U D V

W X S E I Y R A D I U S F

G H I D J K L M N O P Q R

RESOURCE MATERIAL

• C.B.S.E. MATHEMATICS TEXT BOOKS OF CLASSES V, VI, VII

• Encarta 2000