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Rotational symmetry

Rotational Symmetry is a quality of a shape that occurs when the shape seems to be the same after it has been rotated as it did at its initial position.

It is explained by the rotational symmetry of a shape, which states that when an object is rotated about its own axis, the shape of the object remains unchanged. Many geometrical objects appear to be symmetrical when they are rotated 180 degrees or with certain angles, either clockwise or anticlockwise, in the same direction. Some of the examples include squares, circles, hexagons, and other shapes. Because the shape of a scalene triangle is asymmetrical, it does not have symmetry when it is rotated. We know that the term symmetry is a combination of two words,’sync+metry,’ thus we know what it means. As a result, in order to have symmetry, there must be at least two identical orders.

In your everyday life, you may have come across the term symmetry’ a number of times. In two halves of an object, it is a balanced and proportionate similarity that may be found; that is, one half of an object is the mirror image of the other half. Asymmetrical refers to a shape that does not have a symmetrical pattern on it. We may find symmetry everywhere we look, whether it is in the natural world, architectural structures, or works of art. When you flip, slide, or turn an object, you have the opportunity to learn more about it. There are several types of symmetry that can exist:

  • Reflection

  • Translational

  • Translational

Rotational Symmetry

When a figure is rotated about a central point, it is said to exhibit rotational symmetry since it appears exactly as it did before the turn. A number of geometric shapes, such as squares, circles, regular hexagons, and so on, exhibit rotational symmetry.

When studying geometry, you will come across several shapes that are symmetrical rotationally, including the following:

Equilateral triangles are a type of triangle.

  • Squares

  • Rectangles 

  • Circles

  • Regular Polygons

Centre of Rotation

A figure or object with rotational symmetry is defined as having a fixed point around which the rotation happens, which is referred to as the centre of rotation. For example, the centre of rotation of a windmill is located at the centre of the windmill, which is where the blades of the windmill start.

Angle of Rotational Symmetry

The angle of rotation of a figure or object with rotational symmetry is the angle at which the figure or object is turning while rotating around its axis. A square that has been rotated by 90 degrees looks to be the same size as before it has been rotated. This means that for a square, the angle of rotation is 90 degrees.

As an example, a regular hexagon has an angle of symmetry of 60 degrees, a regular pentagon has an angle of symmetry of 72 degrees and so forth.

Order of Rotational Symmetry

The order of symmetry is defined as the number of positions in which a figure can be rotated while maintaining its appearance exactly as it did before the rotation occurred. For example, a star can be rotated five times about its axis and still appear to be the same star each time. Its order of symmetry is hence number five.

 

 

 

 

 

When we investigate the order of symmetry for a regular hexagon, we find that it is equal to 6, because it has six equal sides and is rotated at an angle of sixty degrees.

Rotational Symmetry Letters

When the capital letters of the English alphabet are rotated clockwise or anticlockwise around an axis, several of them exhibit symmetrical behaviour. Z, H, S, N, and O are only a few examples. When these letters are rotated 180 degrees clockwise or anticlockwise, the letters appear to be the same as when they are not.

ROTATIONAL SYMMETRY EXAMPLE

Conclusion

Whenever a figure can be rotated by an angle between 0° and 360°, it is said to have rotational symmetry. When this occurs, the image of the figure coincides with the preimage. Essentially, the least angle at which the figure may be rotated so that it coincides with itself is the angle of rotational symmetry. Many machines rely on rotational symmetry to function properly. Motors would freeze, wheels would cease turning, and the entire universe would come to a grinding halt if rotational symmetry were not there.

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Does rotational symmetry have a formula?

Ans. For example, when an equilateral triangle ABC is rotated about point X, it will take on the same shape a...Read full

What is rotational symmetry and what are some examples?

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Can you tell me the order in which a starfish rotates?

Ans. The perfect starfish has a 5-fold rotational symmetry, with the arms being rotated by 72, 144, 216, 288 ...Read full