Volume

Volume

Volume is the amount of space a 3D shape occupies.

Common units of volume include cubic centimetres (cm3) and cubic metres (m3).

A simple way of working out the volume of a 3D shape is to count how many centimetre cubes would fit into it. 


For example:

This cube has a volume of 1 cm3 or 1 cubic centimetre.

cube_1

The volume of the shape below is 24 cm3.

cube_24


Volume of a prism

A prism is a solid 3D shape that can be cut into slices that are all the same shape.

volume of a prism area of cross-section x length

v = a x l

volume-prism


For example:

A door wedge is in the shape of a trapezium.

What is the volume of the door wedge?


volume of a prism = area of cross-section x length

area of cross-section = area of trapezium = 1/2 x (sum of parallel sides) x height


a =  1/2 x (6 + 2) x 4 = 16

l = 8

v = 16 x 8


volume of the door wedge = 128 cm3

volume-door-wedge

Volume of a cubes and cuboids

volume of a cuboid = length x width x height

v = l x w x h

volume-cuboid


volume of a cube = length x length length 

v = l x l x l

v = l3

volume-cube


For example:

Find the volume of the following shape.

volume-cuboid-ex

Volume = l x w x h = 8 x 5 x 2 = 80 cm3


Find the volume of the following shape.

volume-cube-ex

Volume = l x l x l = 8 x 8 x 8 = 512 cm3

 

 

 

 

 

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