rotational symmetry rotational symmetry if, when you rotate a shape, it looks exactly the same as...
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Rotational Symmetry
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Rotational Symmetry• If, when you rotate a shape, it looks exactly
the same as it did in its original position, then we say that the shape has got rotational symmetry.
• This square has got rotational symmetry.
• It looks exactly the same four times in a full turn.• It has got rotational symmetry order 4.
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Rotational Symmetry• Does this rectangle have rotational symmetry?
• It looks exactly the same twice in a full turn.• It has got rotational symmetry order 2.
Yes, it fits!No, it doesn’t fitNo, it doesn’t fitYes, it fits!
Click to rotate the rectangle.
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Rotational Symmetry in the Alphabet
Which letters have got rotational symmetry?
A B C D E F G H I
J K L M N O P Q R
S T U V W X Y Z
Click to see the answers.
Order 2 Order 2 Order 2
Order 2 Order 2 Order 2
Order 2
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Rotational Symmetry all around usWhich road signs have got rotational symmetry?
Click to see the answers.
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Rotational Symmetry all around usClick to see the road signs with rotational symmetry.
Order 3 Order 2 Order 2
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Rotational Symmetry all around usClick to see more road signs with rotational symmetry.
Order 4 Order 3 Order 2
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Rotational Symmetry all around usClick to see more road signs with rotational symmetry.
Order 3 Order 2
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Rotational Symmetry with Pentominoes
• If you don’t know what a pentomino is, then click here.
• If you have done the pentominoes activity before, then you will know what a pentomino is and how many different pentominoes there are.
• Here they are ...
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Rotational Symmetry with Pentominoes
Which Pentominoes have got rotational symmetry?
Sort them according to their rotational symmetry.
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Rotational Symmetry with Pentominoes
Rotational Symmetry Order 2Rotational Symmetry Order 2 Rotational Symmetry Order 4Rotational Symmetry Order 4
Click to start sorting
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Rotational Symmetry with 7-Pin Polygons
• If you don’t know what a 7-pin polygon is, then click here.
• If you have done the 7-pin polygons activity before, then you will know what a 7-pin polygon is and how many different ones there are.
• Here they are ...
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Rotational Symmetry with 7-Pin Polygons
Which 7-Pin Polygons have got rotational symmetry?Sort them according to their rotational symmetry.
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Rotational Symmetry with 7-Pin PolygonsRotational Symmetry Rotational Symmetry
Order 2Order 2Rotational Symmetry Rotational Symmetry
Order 6Order 6Rotational Symmetry Rotational Symmetry
Order 3Order 3
Click to start sorting
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Now you know all about rotational symmetry!
END OF PRESENTATION
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Pentominoes
A pentomino is made out of five squares that are connected along at least one edge.
These are NOT pentominoes.
Here is an example of a pentomino.
How many different pentominoes can you find?
Click here to return to line symmetry.
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7-Pin PolygonsHere is an arrangement of 7 pins.
Here are some examples of 7-pin polygons.
How many different 7-pin polygons can you find?
Click here to return to line symmetry.
A 7-pin polygon is a closed shape with straight sides with corners on the pins.
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END OF PRESENTATION