If we press the tip of pencil on paper we get a point. A point does not have length breadth or thickness. Now, take a sheet of a paper and a sharpened pencil and make a point on the paper. The points show definite position and are denoted by dot (.).
When we move our pencil across the paper, we get a line. The line can be 'straight' or 'curved'.
What are the different types of lines?
All plane shapes are made up of straight or curved lines or combination of both.
There are two different kinds of lines.
1. Straight line:
We use a ruler to draw straight lines. Straight lines can be horizontal, vertical or slanting. A straight line can be draw between two points. Straight lines are shown below.
2. Curved line:
Curved lines are shown below.
1. Straight Lines:
Observe the edge of this page. Place a ruler along its edge. All its edges are straight line. Straight lines may be drawn in different directions and are given three names. There are three different types of straight lines:
(i) Horizontal lines: The lines drawn horizontally are called horizontal lines.
(ii) Vertical lines: The lines drawn vertically are called vertical lines.
(iii) Oblique or slanting lines: The lines drawn in a slanting position are called oblique or slanting lines.
The explanations on different types of lines will help the kids to understand the difference between the straight lines and the curved lines and how the lines are drawn in different directions in geometry.
2. Curved Lines:
It is an object similar to line but not straight.
We use some curved objects to draw curved lines such as grass, cone, cylinder etc. If we join two points without a ruler, we can join them in many ways.
This will form different curved lines. After drawing a curved line between two points, if we continue on different path on same points we will get closed shape.
Line Segment -
The part of a straight line between two points is called a line segment. In the figure look at the points A and B. A straight line is passing through but only the part of line lying between A and B is line segment. A line segment has two end points. It's length can be measured.
Note: Only one straight line can pass through two points.
To measure a line segment, follow these following steps.
• Take a ruler and put it on the given line segment. e.g. AB
• Read the number at points A and B. The difference between these numbers will be the length of AB.
Let us understand the lines with an activity.
Andrew wanted to understand the straight lines and curved lines. His teacher told him to write his name in capital letters and observe each letter carefully.
A N D R E W
Andrew was happy that his name contains alphabets made up of different types of lines.
Alphabets A, N, E and W are written with horizontal, vertical and slanting lines.
Alphabets like D and R are written with curved lines.
Questions and Answers on Straight Lines and Curved Lines:
1. Observe the number train carefully. Cross the numbers which are made up of only straight lines, tick the numbers which are made up of only curved lines and circle the numbers which are made up of both straight and curved lines.
2. In the given picture color the horizontal lines blue, slant lines red, vertical lines orange and curved lines green. Also write the number of lines in the given space.
Number of Horizontal Lines = __________
Number of Vertical Lines = __________
Number of Slant Lines = __________
Number of Curved Lines = __________