## Volume The volume of an object is the measure of the amount of three dimensional space it takes up.

The volumes and surface areas of certain simple objects such as cubes and prisms can be calculated using formulae.

The surface area of an object is the total area of the outside surfaces of the object.

### Units of Volume

• The basic unit for volume is the cubic metre, written m3.
• 1 cubic metre is the volume occupied by a cube of length 1 metre.
• Smaller volumes are often measured in cubic centimetres, cm3, sometimes called cc.
• 1 litre = 1000 cm3
1 mL = 1 cm3 (1 cc)

### Volume and surface area formulae

Only the cube and cuboid formulae need to be memorised.

 Solid Name Volume Surface Area Cube V = l × l × l = l3 S = 2l2+ 2l2+ 2l2 = 6l2 Cuboid or Rectangular Prism V = (shaded area) × l= (b × h) × l= bhl S = 2bh + 2hl + 2bl Triangular Prism S = bl + al + cl + bh Cylinder   Pyramid S = sum of areas of each face Cone   Sphere  Try this useful activity on the volume and surface area of cuboids and triangular prisms 