In the previous segment we learned about different units of measurement and how a change in the units changes the meaning of the distances measured.
In this segment, we will understand the unit of measurement of length. We will also learn the method of measuring the length of objects using a small scale or a ruler.
What are the types of units of length?
The unit of measurement is a predefined measure used as a standard base for measuring things. Every scale or tool for measuring lengths has demarcations or divisions that indicate these units of length.
We generally use a scale or a ruler to measure the length of objects in the following basic units of length:
- Centimeter
- Millimeter
- Inch
Centimeter
Consider a basic ruler that we use in geometry. On one edge of the ruler, we have 15 divisions that indicate the centimeter units.
Centimeter graduations in a scale
Millimeter
On the same edge, each centimeter can be further divided into 10 units of millimeters. This indicates that 1 centimeter = 10 millimeters.
Millimeter graduation on a centimeter scale
Inch
Now, on the other edge of this ruler, we have the 6 divisions for inches. Each inch can be further divided into 10 units which have no specific name like a millimeter.
Inches graduation on a scale
How to measure lengths using a scale?
We will measure the length of a pencil in centimeters :
- Take a pencil which is smaller than the scale, and place it along the length of the
Measuring the length of an 8 cm pencil using a scale
The tip of the pencil should start where the first big vertical line
- Now observe where the pencil ends and note the value of the big vertical line which corresponds to the end of the
- Note the reading of this vertical line. This is the length of the
Using the same method of measurement, we can find out the length of objects in millimeters as well as inches.