Density of materials

Both bodies in the picture on the right (on the left: Wood, on the right: Aluminum) have an equal mass of 200 g. Nevertheless they strongly differ in its volume.
If their volume would be equal one could notice that the piece of aluminum is by far heavier than the wooden piece.
If one compares several materials in that way (e.g. iron with plastic, Ice and Copper, etc.)one can conclude:

Bodies with the same volume that are made of different materials differ in their masses.

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Density is defined as the ratio between the mass of a body and its volume.

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it applies:

ρ Density of a material
m Mass of the body
V Volume of the body
  • In addition the density of solid and fluid matrials depends on its temperature.
  • The density of gazeous materials depends both on its temperature and its pressure.

Here are some examples for the density of materials.

material kg/m³ g/cm³
Copper 8933 8,933
Aluminum 2702 2,702
Gold 19290 19,290
Water 998 0,998
Ice 917 0,917
Air 1,2929 0,0012929
Helium 0,1785 0,0001785

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