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Rotational SymmetryRotational Symmetry

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5

7 21

Rotational SymmetryAll 2 dimensional shapes have some rotational symmetry. The degree of rotational symmetry that an object has is known as its order.

Order 1 Order 2 Order 3 Order 4

For shapes that have “order 2” rotational symmetry or higher, a single centre of rotation can be located.

For shapes that have only “order 1” rotational symmetry a centre of rotation can be found anywhere within it.

Rotational Symmetry

The order of rotational symmetry that an object has is the number of times that it fits on to itself during a full rotation of 3600

Order 1

Rotational Symmetry

Order 11

2

Order 2

The order of rotational symmetry that an object has is the number of times that it fits on to itself during a full rotation of 3600

Rotational Symmetry

Order 11

2

Order 2

12

3

Order 3

The order of rotational symmetry that an object has is the number of times that it fits on to itself during a full rotation of 3600

Rotational Symmetry

Order 11

2

Order 2

12

3

Order 312

3 4

Order 4

The order of rotational symmetry that an object has is the number of times that it fits on to itself during a full rotation of 3600 .

What is the order of rotational symmetry of the shape below?

Rotational Symmetry

1

23

4

5

What is the order of rotational symmetry of the shape below?

Order 5

Rotational Symmetry

What is the order of rotational symmetry of the shape below?

Rotational Symmetry

1

2

3

4

5

What is the order of rotational symmetry of the shape below?

Order 6

Rotational Symmetry

6

Equilateral Triangle

An equilateral triangle has rotational symmetry of order ?

Equilateral Triangle

An equilateral triangle has rotational symmetry of order ?

Equilateral Triangle

An equilateral triangle has rotational symmetry of order ?

12

33

Square

A square has rotational symmetry of order ?

Square

Square

A square has rotational symmetry of order ?

Square

A square has rotational symmetry of order ?

12

3

4

4

Pentagon

Regular Pentagon

A regular pentagon has rotational symmetry of order ?

Regular Pentagon

A regular pentagon has rotational symmetry of order ?

Regular Pentagon

A regular pentagon has rotational symmetry of order ? 5

1

23

4

5

Hexagon

Regular HexagonA regular hexagon has rotational symmetry of order ?

Regular HexagonA regular hexagon has rotational symmetry of order ?

1

23

4

5 6

Regular HexagonA regular hexagon has rotational symmetry of order ? 6

Regular OctagonA regular octagon has rotational symmetry of order ?

Octagon

1

2

34

5

6

Regular OctagonA regular octagon has rotational symmetry of order ? 8

7 8

Rectangle

RectangleA rectangle has rotational symmetry of order ?

2

1

2

RectangleA rectangle has rotational symmetry of order ?

Parallelogram

ParallelogramA parallelogram has rotational symmetry of order ?

2

1

2

ParallelogramA parallelogram has rotational symmetry of order ?

Isosceles TriangleAn isosceles triangle has rotational symmetry of order ?

1

1

Isosceles TriangleAn isosceles triangle has rotational symmetry of order ?

Scalene

Scalene TriangleAn scalene triangle has rotational symmetry of order ?

1

1

Scalene TriangleAn scalene triangle has rotational symmetry of order ?

Isos Trapezium

Isosceles TrapeziumAn isosceles trapezium has rotational symmetry of order ?

1

1

Isosceles TrapeziumAn isosceles trapezium has rotational symmetry of order ?

Trapezium

TrapeziumA trapezium has rotational symmetry of order ?

1

1

A trapezium has rotational symmetry of order ?

Trapezium

A kite has rotational symmetry of order ?

Kite

Kite

1

1

A kite has rotational symmetry of order ?

Kite

Kite

Rhombus

A rhombus has rotational symmetry of order ?

Rhombus

2

1

A rhombus has rotational symmetry of order ?

Rhombus

2

Ellipse

An ellipse has rotational symmetry of order ?

Ellipse

Ellipse

2

1

An ellipse has rotational symmetry of order ?

Ellipse

2

Rotational SymmetryState the order of rotational symmetry for each shape below:

1 2 3 4

5 6 7 8

9 10 11 12

Order 6 Order 2 Order 3 Order 2

Order 1 Order 3 Order 2 Order 5

Order 4 Order 1 Order 6 Order 8

Rotational SymmetryState the order of rotational symmetry for each shape below:

13 14 15 16

17 18 19 20

21 22 23 24

Order 4 Order 1 Order 2 Order 5

Order 2 Order 4 Order 6 Order 3

Order 5 Order 4 Order 3 Order 1

Now..it’s the time for…Now..it’s the time for…

To ignite your minds..To ignite your minds..To ignite your minds..To ignite your minds..

@ First, Observe the given Picture carefully.

@ Try to Imagine the rotation

@ Concentrate on the inner designs also

@ Each question carries ‘1m’ as usual

@ Time limit for each Work sheet is ‘5 min.,’ only

# WRITE ONLY THE ORDER OF ROTATIONAL SYMMETRY IN THE GIVEN BOXES

Worksheet 1

Rotational SymmetryRotational SymmetryState the order of rotational symmetry for each shape below:

1 2 3 4

5 6 7 8

9 10

Worksheet 2

Rotational SymmetryRotational SymmetryState the order of rotational symmetry for each shape below:

13 14

15 16 17 18

19 20

11 12

Credits & Acknowledges !Credits & Acknowledges !

• The master trainer. Mr. N. Uma Srinivas• MS Office• MS Encarta• www.whiteboardmath.com• www.teachingideas.com• www.pppst.com• Perspector panel• VIPS Knowledge Centre.