In English, Rotation means to turn around an object around a center. When an object rotates around a centric Point then it is called as rotation. When any object rotates in three dimensional space about an imaginary line we call it as rotation. Just like this, we can give many definitions for a rotation. If we want to see the real world example of a rotation then we can take an example of earth. Earth revolves around the sun, this is also rotation. Moon revolves around the earth, it is also called rotation. Now the meaning of rotation is clear to you.
Rotational SymmetryBack to Top
On the other hand, if we look at the Isosceles Triangle or the Scalene Triangle, we observe that figure does not look same at any angular rotation, but after completing the rotation of 360 degrees it looks as it is. So the order of rotation is 1 and the angle of rotation is 360 degrees.
Have a look on another geometrical figure, say a Square. A square after the rotation of 90 degrees, take the exact shape, so the angle of the rotation of the square will be 90 degrees, 180 degrees, 270 degrees and 360 degrees. Thus we can say that the order of rotation of the square will be 4. Similarly, the order of rotation of the Rectangle will be 2 and the angle of rotation of the rectangle is 180 degrees.
Once we know the order of rotation of any figure, we can find the angle of rotation by applying the formula 360 / order of rotation.
By applying the same formula we say for equilateral triangle angle of rotation = 360 / 3 = 120 degrees.
For a square angle of rotation = 360 / 4 = 90 degrees and for the rectangle angle of rotation = 360 / 2 = 180 degrees.