Volume

The volume of an object is the amount of space it occupies. The S.I. unit for volume is the cubic metre. The symbol for the cubic metre is m^3.Other commonly used units for volume are the cubic centimetres , litre and the millimetre.

We can measure the volume of liquids using a measuring cylinder, a burette or a pipette.

Regular solids: We can measure the volume of regularly shaped solids by using the right formulae.

Cube: volume = length x length x length

Cuboid: volume = length x breadth x height

Cylinder: volume = π x radius²x height

Sphere: volume = 4/3 x π x radius³

^{Cone: volume = 1/3 x π x radius2x height}

^{Irregular solids: The volume of a small irregular solid can be measured by DISPLACEMENT, using a measuring cylinder or a displacement can/ eureka can.}

^{Experiment 1: Using a measuring cylinder}

^{1 Observe and note down the amount of water in the measuring cylinder.}

^{2 Tie the object with a piece if string and lower it slowly until it is completely submerged. Note the new water level. Hence the volume of the object is the volume of water displaced by the object (new water level - original water level).}

Experiment 2: using a displacement can (Eureka can)

1 Fill a displacement can with water to the level of the spout. Allow excess water to flow into a container. When the water stops flowing, replace the container with a dry, empty measuring cylinder.

2 Tie a piece of string to the object and lower it into the displacement can till it is completely submerged. Some water is displaced into the measuring cylinder. Note the volume of water displaced by the object. Hence, the volume of the object is the volume of water displaced by the object.

How do we measure the volume of a cork?

Since the density of a cork is less than the density of water, the cork will float and thus, it will not displace the same volume of water as the volume of the cork.

How we do it:

1)Prepare a beaker of water

2)Take note of the water level

3)Suspend the cork slowly with a weight attached to it into the beaker of water so it won't float.

4)Record the new water level

5)Repeat steps 1 to 4 without the cork

6)Subtract the initial water level from the new water level

Source: Lower Secondary Science Matters

Published by Marshall Cavendish Education