Chapter 11.3, Problem 4CYU

To determine

To find: whether the blades of the windmill has rotational symmetry or not , if yes, to

find the angle of rotational.

Answer to Problem 4CYU

The windmill has rotational symmetry and angle of rotation is ${90}^0$ .

Explanation of Solution

Given information:

Consider

Calculations:

Consider the given figure,

It has four wings of equal length. The centre angle is $={360}^0$

The angle between any two wings $={90}^0$

If we rotate the windmill by ${90}^0$ then the resultant figure is same as before.

Hence,

The windmill has rotational symmetry and angle of rotation is ${90}^0$ .