Measurement - Length, Mass, Capacity

Measurement - Length, Mass, Capacity

Measuring Length

Length

 Length is a measure of how long an object is. Different lengths are measured in different units.

Units of Measuring Length

Centimetre: Smaller lengths are measured in centimetres. The length of a pen, pencil, paper pin, eraser etc are measured in centimetres. We denote ‘centimetre’ by ‘cm’

Metre: The standard unit of length is metre. The length of a floor or cloth, height of a pole etc are measured in metres. We denote ‘metre’ by ‘m’.

Kilometre: Longer lengths and distances are measured in kilometres. The distance between two towns, heights of the peaks or mountains etc are measured in kilometres. We denote ‘kilometre’ by ‘km’

Relation between Units of Length

John and Sara want to measure the length of different objects.

They can use ruler and measure the length in centimeters.

We can write centimeters as ‘cm’

The pencil is 5 cm long.

The eraser is 2 cm long.

We can also measure length in meters. We can write as m. We use meters as m. We use meters for longer objects.

1m = 100cm

 Look at the meter ruler. It is 1m long.

The plant is less than 1m.

The blackboard is almost 1m tall.

Look at objects. Tell whether we will use meters or centimetres to measure the given objects.

Examples:

The distance between John’s school and Charminar is 5km

The distance between Sara’s school and Railways station is 10km

Johnny draws a line. It is 4 cm long.

 John draws a line. It is 5 cm long.

What is the length of both lines?

The total length of both lines 9 cm