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Topic 1.4:Density
Defining Density
An object’s density is its mass occupied per unit volume and is measured in
kg/m3 or g/cm3.
The formula for density of a solid is ρ=m/v, where ρ = density,
m = mass and v = volume.
The density of an object is a value of how concentrated its mass is.
The density of water is 1000 kg/m3 OR 1 g/cm3
Calculating density of a liquid
The density of a liquid can be calculated using the formula ρ=m/v.
Firstly, the liquid can be added to a measuring cylinder. Then, the volume
can be measured.
The mass of the measuring cylinder with and without the liquid should be
measured, using a balance.
Mass of liquid = Mass of measuring cylinder with liquid – Mass of
measuring cylinder without liquid
The formula above can be used to find the density since both mass and
volume are known.
Calculating density of Solids
The equation of density, ρ=m/v, is once again used to find the density of
solids.
For a regular solid, the mass can be measured using a balance and the
volume can be calculated by measuring dimensions and using the
appropriate formula. Then, the equation above can be used to find density.
For an irregular solid, the mass can still be measured using a balance.