When an object (or) shape is rotated around its central point, it looks the same. The rotation can be a complete rotation or a partial rotation with some angle. This concept is called rotation symmetry.
We can observe rotational symmetry around us in many objects like ceiling fans, windmill, wheel etc.
To understand the concept of rotation, we here have a simple example to understand better hands of a clock.
- We know that the hands of a clock rotate only in one direction and along with a fixed point. This fixed point is the center of the clock.
- This movement of rotation of the hands of a clock is called clockwise rotation.
- When an object rotates in opposite orientation to the hands of a clock, this movement is called anti-clockwise rotation.
Figure - 2
> When an object rotates in the clockwise or anti-clockwise direction, its shape or size doesn't change.
> The rotation of any object happens along with a fixed point (as in the hands of the clock), This fixed point is called the center of rotation.
> And every object rotates with a certain angle along the center of rotation, which is called the angle of rotation.
> We know that one complete turn is a rotation of \(360°\), the one-half turn is a rotation of \(180°\), the one-quarter turn is a rotation of \(90°\).