Post on 27-Dec-2015
Roational SymmetreyRoational Symmetrey
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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.
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 360 degrees.
Rotational SymmetryThe order of rotational symmetry that an object has is the number of times that it fits on to itself during a full rotation of 360 degrees.
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 360 degrees.
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 360 degrees.
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 360 degrees.
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
Equilateral Triangle
An equilateral triangle has rotational symmetry of order ?
Regular Polygons
Equilateral Triangle
An equilateral triangle has rotational symmetry of order ?
Equilateral Triangle
An equilateral triangle has rotational symmetry of order ?
12
33
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
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 ?
Isos Tri
Isosceles TriangleAn isosceles triangle has rotational symmetry of order ?
Isos Tri
1
1
Isosceles TriangleAn isosceles triangle has rotational symmetry of order ?
A kite has rotational symmetry of order ?
Kite
Kite
1
1
A kite has rotational symmetry of order ?
Kite
Rhombus
A rhombus has rotational symmetry of order ?
Rhombus
2
1
A rhombus has rotational symmetry of order ?
Rhombus
2
Questions 1
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
Worksheet 1
Rotational SymmetryState the order of rotational symmetry for each shape below:
1 2 3 4
5 6 7 8
9 10 11 12