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Density

Density tells you how much mass is packed into a given volume, and is a property of the substance, not of the object's size. Water has a density of about 1000 kg/m³, that is 1 kg per liter, and is a useful reference point for other substances.

ρ=mV\rho = \dfrac{m}{V}density

Symbols

ρ\rhodensitykg/m³
mmmasskg
VVvolumem³

Example

A metal piece has m=0.89m = 0.89 kg and V=100V = 100 cm³ =1.0⋅10−4= 1.0\cdot 10^{-4} m³. The density is ρ=0.89/(1.0⋅10−4)=8900\rho = 0.89/(1.0\cdot 10^{-4}) = 8900 kg/m³, likely copper.

Remember to convert cm³ to m³ (11 cm³ =10−6= 10^{-6} m³) before computing the density in kg/m³.
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Part of Foundations of Physics: Pressure, density and heat.