NCERT Solutions for Class 6 Maths Chapter 4 Exercise 4.1
NCERT Solutions for Class 6 Maths Chapter 4 Exercise 4.1 (Ex. 4.1) Basic Geometrical Ideas in Hindi and English Medium updated for academic session 2020-2021. Videos related to 6th Maths exercise 4.11 is also given below to with solution and explanation separately. These grade 6 Maths solutions are also useful for state board students.
Class 6 Maths Chapter 4 Exercise 4.1 Solution
|Chapter: 4||Basic Geometrical Ideas|
|Exercise: 4.1||NCERT Solutions in Hindi and English|
CBSE NCERT Class 6 Maths Chapter 4 Exercise 4.1 Solution in Hindi and English Medium
Class 6 Maths Chapter 4 Exercise 4.1 Solution in Videos
Introduction of Geometry
The term ‘Geometry’ is the English equivalent of the Greek word ‘Geometron’. ‘Geo’ means Earth and ‘metron’ means measurement, i.e., geometry means measurement of the earth. The geometry shaped up when men felt the need to measure their lands while buying and selling. Various shapes and figures with which we deal in geometry are called geometrical figures. In geometry, we learn about the construction of geometrical figures and study their basic properties. Thus, we can say that geometry is the science of properties and relations of figures.
Basic Terms in Geometry
In this chapter, we shall learn about some basic concepts and terms in geometry. There are three basic terms, namely Point, Line and Plane which form the building blocks of geometry. These terms cannot be precisely defined. However, we give some examples to illustrate the meaning of these terms.
A point is a mark of position. A point depicts the exact position of an object. It does not have any size. It has neither length, nor breadth, nor height. A small dot (.) made by a sharpened end of pencil on a plane sheet of paper, a tiny prick made by a fine pin on a paper, the corners of a rectangle, the tip of an ice-cone etc. are all physical examples of a point.
The word ‘line’ usually refers to a ‘straight line’.
A line has no width. It has just length. It is absolutely straight and can extend indefinitely in both directions.
Note: In geometry, by a line we mean the straight line as a whole and not a part of it. Since a line extends indefinitely in both the directions, it cannot be drawn or shown wholly on a sheet of paper.
Every solid has a surface which may be flat or curved. The surface may be smooth or rough also.
For example, the surface of the blackboard is flat and the surface of a cricket ball is curved. Flat surfaces are known as plane surfaces and other surfaces are known as curved surfaces.
So, a plane is a flat surface which extends indefinitely in all directions
What do you mean by segment of a line?
A line has no width. It has just length. It is absolutely straight and can extend infinitely in both directions. But practically we cannot draw a line which length is infinite, so we use a piece of line or segment of a line.
Who first invented Geometry?
6th century BC in Greek, Euclid was a great mathematician and often called the father of geometry.
What do you mean by plane in geometry?
In geometry, by a plane we mean the whole plane and not just a portion of it. Since a plane extends indefinitely in all the directions, we cannot draw a plane on a sheet of paper. We can show only a part of it on the paper by drawing a rectangle or a parallelogram.