NCERT Solutions for Class 6 Maths, Chapter 5 - Understanding Elementary Shapes

All the shapes we see around us are formed using curves or lines. We can see corners, edges, planes, open curves and closed curves in our surroundings. We organise them into line segments, angles, triangles, polygons and circles. We find that they have different sizes and measures. This chapter will help you in understanding the elementary shapes.

In NCERT Maths Book Class 6, Chapter 5 Solutions, as you progress through the chapter you will learn different elementary shapes, how to measure the length of line segments, angles and their categories. Further, you will study some subcategories of angles, how to measure the angles through a protractor and with some formulas, perpendicular lines, how the triangles are classified. As you move towards the end of this chapter you will learn quadrilaterals, polygons and some three-dimensional shapes.

Let’s take a look at topics and sub-topics of Class 6 Maths Chapter 5, Understanding Elementary Shapes

5.1 Introduction

5.2 Measuring Line Segments

5.3 Angles – ‘Right’ and ‘Straight’

5.4 Angles – ‘Acute’, ‘Obtuse’ and ‘Reflex’

5.5 Measuring Angles

5.6 Perpendicular Lines

5.7 Classification Of Triangles

5.8 Quadrilaterals

5.9 Polygons

5.10 Three Dimensional Shapes

In Class 6 Maths NCERT Solutions Chapter 5, you will learn – 

Section 5.2 – In this section, you will learn how to measure line segments. The distance between the endpoints of a line segment is its length. A graduated ruler and the divider are useful to compare lengths of line segments. A line segment is a fixed portion of a line. This makes it possible to measure a line segment. As you move further in this section you will learn how to compare two line segments. It can be done by observation, tracing and by using a ruler and a divider. Further, in this section, you will study positioning error. To avoid it the eye should be correctly positioned, just vertically above the mark.

Section 5.3 – You have studied angles in the previous chapter. This section basically deals with the first two type of angles – right and obtuse. When a hand of a clock moves from one position to another we have an example of an angle. One full turn of a hand is 1 revolution. A right angle is 1/4 revolution and a straight angle is 1/2 a revolution. The measure of a right angle is 90° and that of a straight angle is 180°. As you move further in this section you will study complete angle.

Section 5.4 – This section deals with the next three types of angles – acute, obtuse and reflex. An angle is acute if it’s measure is smaller than that of a right angle and is obtuse if it’s measure is greater than that of a right angle but less than a straight angle. Rooftop, see-saw, opening book are some examples of an acute angle. House, book reading desk and hands of a clock at 7 pm are some examples of an obtuse angle. A reflex angle is larger than a straight angle.

Section 5.5 – This section will help you in measuring angles through an activity. Cut of a circular sheet of paper. Fold it twice to get four equal parts. The folds will give you each of the angles measuring 90°. If you fold it further then you will get 45°. This can also be done with the help of a protractor.

Section 5.6 – In this section, you will learn perpendicular lines. Any two lines which are interesting are said to be perpendicular if the angle between them is 90°. The perpendicular bisector of a line segment is perpendicular to the line segment that divides it into two equal parts. As you move further in this section you will learn how to draw perpendicular bisector of a line using compass and protractor.

Section 5.7 – This section deals with the classification of triangles. Triangles can be classified on the basis of their angles. If each angle is acute then the triangle is called an acute-angled triangle. If anyone of the angle is a right angle then the triangle is right-angled. Similarly, if anyone of the angle is obtuse then the triangle is said to be obtuse-angled. Further, triangles can also be classified on the basis of their sides namely – scalene, equilateral and isosceles.

Section 5.8 – You have studied quadrilaterals in the previous chapter. It is a polygon which has four sides. This section will brief you with some types of quadrilaterals. There are five types of quadrilaterals – rectangle, square, parallelogram, rhombus and trapezium.

Section 5.9 – So far you have studied polygons of three or four sides ( known as triangles and quadrilaterals ). This section will extend the idea of a polygon to figures with more number of sides. We may classify polygons according to the number of their sides. Polygons with five, six and eight sides are known as Pentagon, hexagon and octagon respectively.

Section 5.10 – Towards the end of this chapter this section deals with some more three-dimensional shapes that we see in our day to day life. Cubes, cuboids, spheres, cylinders, cones, prisms and pyramids are some of them. The ice cream is in the form of a cone. A cold drink can be thought of a cylinder. Playing die is an example of a cube. Matchbox is an example of a cuboid.

In this chapter, you are provided with several examples along with their solutions for a clear understanding of elementary shapes. To know more about NCERT Solutions for Class 6 Maths Chapter 5 Understanding Elementary Shapes, you should explore the exercises below. You can also download the Understanding Elementary Shapes Class 6 NCERT Solutions PDF, solved by expert maths trainers. You can also refer online to Class 6 Maths Chapter 5 Worksheet PDF.