Angle of Rotational Symmetry

Q. What is the angle of rotational symmetry of a regular pentagon?

1. ${36}^{\circ }$
2. ${60}^{\circ }$
3. ${108}^{\circ }$
4. ${72}^{\circ }$

Q.

Can we have a rotational symmetry of order more than 1 whose angle of rotation is

(i) 45°?

(ii) 17°?

Q. What is the order of symmetry of a regular polygon whose angle of rotational symmetry is 40°?

1. 6
2. 15
3. 9
4. 4

Q.

We say that a figure has a rotational symmetry of more than 1 when __.

1. When you rotate a figure for 90° and get the original figure

2. When you rotate a figure for 180° and get the original figure

3. When you rotate a figure for 270° and get the original figure

4. When you rotate a figure for 360° and get the original figure

Q.

Which of the following cannot be the angles of rotational symmetry for a regular polygon with odd number of sides?

1. ${40}^{\circ }$

2. ${120}^{\circ }$

3. ${72}^{\circ }$

4. ${180}^{\circ }$

Q. Which of the following cannot be possible angle(s) of rotational symmetry of a figure?

1. ${16}^{\circ }$
2. ${20}^{\circ }$
3. ${24}^{\circ }$
4. ​​​​​${22}^{\circ }$

Q. Rotating the given regular hexagon by an angle of ${60}^{\circ }$ yields the same figure as the original. At what other angles will this happen for the figure?

1. ${120}^{\circ }$
2. ${180}^{\circ }$
3. ${240}^{\circ }$
4. ${310}^{\circ }$

Q. If the angle of rotation of a regular polygon is ${90}^{\circ },$ then its order of rotational symmetry is 2.

1. False
2. True

Q.

(a) In a square, red balls are arranged along one diagonal and yellow balls are arranged along another diagonal. Find the rotational symmetry of the given arrangement?

(b) If ‘X’ is the order of rotation of a regular polygon with ‘n’ sides and ‘Y’ is the number of angles of rotation, what is the value of (X – Y – 1)? [4 MARKS]

Q. What is the angle of rotational symmetry of a square whose one diagonal is red and the other yellow in colour?

1. ${180}^{\circ }$
2. ${90}^{\circ }$
3. ${45}^{\circ }$
4. ${360}^{\circ }$

Q. Which figure below shows two quadrilaterals related by both rotational symmetry and line symmetry?

1. Figure ii
2. Figure iii
3. None of these
4. Figure i

Q. how many lines of symmetry and rotational symmetry does a pentagon have?

Q.

Statement 1: Regular polygons have finite lines of symmetry.

Statement 2: Circle has infinite lines of symmetry.

Statement 3: Circle is a polygon with infinite sides.

Statement 4: Circle is a regular polygon with infinite sides.

Which of the above statements is/are incorrect?

1. 1

2. 2

3. 3

4. 4

Q. All figures when rotated come back to its original position. The angle of rotation is

1. ${90}^o$
2. ${180}^o$
3. ${270}^o$
4. ${360}^o$

Q.

If a fan has 3 blades, then its degree of rotation is _____.

1. ${120}^{\circ }$

2. ${180}^{\circ }$

3. ${150}^{\circ }$

4. ${90}^{\circ }$

Q. ${70}^{\circ }$ cannot be the angle of rotational symmetry of a figure.

1. False
2. True

Q. The angle of rotational symmetry of a square is __.

1. 45°
2. 60°
3. 90°
4. 180°

Q.

Can we have a rotational symmetry of order more than 1 whose angle of rotation is

(i) 45°?

(ii) 17°?