- The process of comparing an object with a standard unit of measurement.
- Here, the known fixed quantity is called a unit .
- Example - Length of the table is 10 length of Handspan.
- Here, 10 is the number and Handspan is the unit selected for measurement.
Standard unit of Measurement:
Ancient Units:
- People used length of foot , width of fingers and distance of a step to measure things in different parts of the world.
- Length of elbow to the finger , known as cubit was also used as a unit of measurement in Egypt.
- Yard of cloth was measured by the distance between the outstretched arm and their chin, Romans measured the yard of cloth with their pace or steps.
- Angul (Finger) or Mutthi (fist) were used for measuring small length
Disadvantage:
Since everyone’s body parts were of different sizes , using these units for measurement can be very confusing . Therefore, in 1790, the French created a standard unit of measurement called the metric system .
Modern unit:
- For the sake of uniformity , scientists all over the world make use of the International system of unit (SI UNIT).
- SI units of length is Metre.
- 1 metre (m)=100 centimetre (cm)
- 1 centimetre (cm)=10 millimetre (mm)
- 1 kilometre (km)=1000 metre (m)
