Page 155 - Active Science 5 Ebook and Activity

Measurement of Length

When your father takes you to buy a cloth
from a cloth merchant, he (the shopkeeper)
uses a steel rod (usually one metre long)

to measure the length of the cloth. Cloth
is measured in metres with the help of a
measuring rod. Metre is the standard unit
of measurement of length. The smaller

lengths like the length of a pencil and
book is measured in millimetres (mm) and
centimetres (cm). The larger lengths like Ruler Measuring tape
distance between two towns are measured

in kilometre (km).

You can convert the units of different lengths as follows:
1 kilometre = 1000 metres

1 metre = 100 centimetres
1 centimetre = 10 millimetres Factual Study

The Great Wall of China is the longest
Thus, the largest unit of length is kilometre
(km) and smallest unit is millimeter (mm). structure ever built by humans. The
length of the Great Wall of China is
A ruler and a measuring tape are used to 21,196.18 kilometres.The highest point
measure small lengths. of the wall is around 26 feet (8 metre).

Let’s Recapitulate

Tick the correct statements.

1. Finding length, mass, capacity and time is called measurement. _____
2. In early times, people used measuring devices for measurement. _____
3. A fixed standard of measurement is called unit. _____

4. Smallest unit of measurement is millimetre and centimetre. _____
5. Largest unit of measurement is metre. _____

Measurement of Mass

The amount of matter present in a particular body or object is called mass of the body.

Kilogram (kg) is the standard unit of measurement of mass. Milligram (mg) and gram
(g) are smaller units of measurement of mass. For example, vegetables and fruits are
purchased in kilograms, while gold and silver are purchased in grams.

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