ORDER OF ROTATIONAL SYMMETRY
Definition Of Order Of Rotational Symmetry
The number of positions a figure can be rotated to, without bringing in any changes to the way it looks originally, is called its Order of Rotational Symmetry.
More About Order of Rotational Symmetry
Order of rotational symmetry depends upon the number of equal sides that a regular polygon has.
Examples of Order of Rotational Symmetry
A square has rotational symmetry of order 4.
A rectangle has rotational symmetry of order 2
An equilateral triangle has rotational symmetry of order 3
Video Examples: Order of Rotational Symmetry
Solved Example on Order of Rotational Symmetry
Ques: Find the order of rotational symmetry of the figure shown.
Choices:
A. 6
B. 7
C. 8
D. 12
Correct Answer: A
Solution:
Step 1: Order of rotational symmetry depends upon the number of equal sides that a regular polygon has.
Step 2: The given figure has 6 equal sides.
Step 2: So, it has the rotational symmetry of order 6..
Quick Summary
- Order of rotational symmetry is the number of times a shape looks the same during a full rotation.
- Regular polygons have rotational symmetry equal to the number of sides.
🍎 Teacher Insights
Use physical objects and rotations to demonstrate the concept. Emphasize the difference between rotational and reflectional symmetry. Use examples of both regular and irregular polygons.🎓 Prerequisites
- Symmetry
- Rotations
- Polygons
Check Your Knowledge
Q1: What is the order of rotational symmetry of a square?
Q2: What is the order of rotational symmetry of a rectangle?
Q3: What is the order of rotational symmetry of a regular hexagon?
Frequently Asked Questions
Q: What is rotational symmetry?
A: Rotational symmetry is when a shape looks the same after a rotation of less than 360 degrees.
Q: How do you find the order of rotational symmetry?
A: Determine how many times the shape looks identical during one full rotation.