RBSE Class 6 Maths Notes Chapter 5 Understanding Elementary Shapes

These comprehensive RBSE Class 6 Maths Notes Chapter 5 Understanding Elementary Shapes will give a brief overview of all the concepts.

RBSE Class 6 Maths Chapter 5 Notes Understanding Elementary Shapes

→ A line segment is a fixed portion of a line.

→ The distance between the end points of a line segment is its length.

→ When a hand of a clock moves from one position to another position we have an example for an angle.

→ One full turn of the hand is 1 revolution. A right angle is 1/4 revolution and a straight angle is 1/2 a revolution.

→ We use a protractor to measure the size of an angle in degrees. The measure of a right angle is 90° and hence that of a straight angle is 180°. An angle is acute if its measure is smaller than that of a right angle and is obtuse if its measure is greater than that of a right angle and less than a straight angle. A reflex angle is larger than a straight angle.

→ Two intersecting lines are perpendicular if the angle between them is 90°.

→ The perpendicular bisector of a line segment is a perpendicular to the line segment that divides it into two equal parts.

→ Triangles can be classified as follows based on their angles and lengths of sides :

• Each angle is acute, it is called an acute angled triangle.
• One angle is right angle, it is called a right angled triangle.
• One angle is obtuse, it is called an obtuse angled triangle.
• All the three sides unequal is called a scalene triangle.
• Two sides equal is called an isosceles triangle.
• All the three sides equal is called an equilateral triangle.

→ Polygons are named based on their sides :

→ Quadrilaterals are further classified with reference to their properties.