Measurement: Capacity/Volume
The SI unit for measuring Volume is the
cubic metre, m³.
The Capacity is how much liquid can be contained within the volume of an object and is measured in litres, l.
At Key Stage 2, we normally think of capacity in terms of how much liquid an object can contain and we talk about its capacity in litres. However it is important to understand that volume and capacity are linked and both are often used to describe capacity.
A 10cm cube, 1000 cm³, will hold 1 litre ... 1 litre = 1000 cm³
A 1 metre cube, 1 m³, will hold 1000 litres ... 1000 litres = 1 m³ 

How much water does this aquarium contain?
It measures 2 m wide, 1 m high and 0.5 m deep.
Volume is width x height x depth ... 2 x 1 x 0.5 = 1 m³
1 m³ = 1000 litre ... The aquarium holds 1000 litres.

How much juice does this carton contain?
It measures 12.5 cm wide, 20 cm high and 8 cm deep.
Volume is width x height x depth ... 12.5 x 20 x 8 = 2000 cm³
1000 cm³ = 1 litre ...... 2000 ÷ 1000 = 2
The carton holds 2 litres of juice. 

For smaller amounts of liquid we use the millilitre, ml. 1000 ml = 1 litre
A teaspoon is approx 5 ml, a dessert spoon is 10 ml and a tablespoon is 15 ml
A bottle of mineral water could be 330 ml or 500 ml
A carton of juice is 1 litre
In the UK, we also use imperial units to measure capacity  pints and gallons.
There are 8 pints in a gallon.
A pint is approximately half a litre.
A gallon is approximately 4.5 litres.

The kitchen is a good place to measure different capacities  use a measuring jug to check the capacity of different items  cups, glasses, bottles etc.
They normally have both metric and imperial measurements, so are really useful for comparing the two types of unit.


Try this Measures Quiz from BBC Bitesize
Practice working with Capacity with these worksheets from Primary Resources
Investigating Capacity Filling 1 litre Capacity ml/l
Capacity Word Problems Capacity Word Problems 2
Converting Capacities

