rotational symmetry 5 7 2 1 all 2 dimensional shapes have some rotational symmetry. the degree of...
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Rotational SymmetryRotational Symmetry
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
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 .
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
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
This shape has rotational symmetry every 120 degrees.
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
A square has rotational symmetry every 90 degrees.360 ÷4 = 90
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
A regular pentagon has rotational symmetry 5 times. 360 degrees divide by 5 means it matches up every 72 degrees.
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
The hexagon has rotational
Symmetry 6 times. 360 ÷6.
It has symmetry eveyy 60 degrees
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 The regular octagon has 8
points of rotational
symmetry. It matches up
360÷8 or every 45 degrees !
Rectangle
RectangleA rectangle has rotational symmetry of order ?
2
1
2
RectangleA rectangle has rotational symmetry of order ?
This rectangle is not a regular polygon. It will show rotational symmetry only twice. 360 degrees÷2 every 180 degrees
Parallelogram
ParallelogramA parallelogram has rotational symmetry of order ?
2
1
2
ParallelogramA parallelogram has rotational symmetry of order ?
How many degrees must this parallelogram rotate before it shows symmetry?
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 TrapezoidA isocelese trapezoid has rotational symmetry of order ?
1
1
Isosceles TrapeziumAn isosceles trapezioid has rotational symmetry of order ?
Since there is no symmetry until it has rotated the entire 360 degrees, the order of symmetry is one.
Trapezium
Right TrapezoidA trapezium has rotational symmetry of order ?
1
1
A right trapezoid has rotational symmetry of order ?
Right Trapezoid
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