A few examples of how density applies to everyday life are in ship building, helium balloons, pipe design and the fact that ice floats on water. Density is defined as an object's mass per unit volume.
The common density example of ice floating on water can be attributed to the Archimedes principle. The principle states that an object is buoyed by a force that is equal to the weight of the volume of liquid it displaces when it is placed in the liquid.
Two areas of transportation where density is important are in the ship and airplane industries. Manufacturers of these pieces of equipment take into account the densities of the materials used to construct the machines, which help obtain the final weight necessary to keep the ship or aircraft afloat in water or air.
Helium balloons are yet another example of density used by the general public. They are able to float in the air because helium gas density is lighter than the density of air. Finally, pipe design is an area in which density plays a role in order to ensure that materials flow through the pipe. Fluids with greater density are harder to push through a pipe than those with lesser density.