Mass vs Density
In physics, there are several physical properties that help quantify or describe matter. Properties like mass and density are often sharing close relationships in terms of mathematical formulas. It is no wonder that these two are often confused with each other.
Mass quantifies the amount of matter present in a certain object that is usually expressed in unit grams or kilograms. Unlike weight, the mass of matter or objects is not influenced by gravity thereby making the mass of something similar wherever it is placed in any location on Earth as well as on other planets having varying gravitational strengths. For example, person A might weigh 60 kg. on Earth while weighing 50 kg. on another planet having less gravitational pull. In another example, a rock having a mass of, let’s say, 10 kg. will still have the same amount of mass on other planets. Without gravity, it is safe to say that a particular matter will no longer have weight but still possess mass.
Density is a very related property but must be understood as a completely different concept from either weight or mass. Density quantifies how much mass is present in a certain matter or object with respect to volume (per unit volume). Water, for example, has a density of 1 gm/cm3. In practical applications, ships float on water, no matter how heavy they weigh, because ships still have less density as opposed to the general density of water. The ship’s volume is so great that it tends to dwarf its mass leading to a smaller density. Other substances that are denser than water will no longer float (i.e. a fist-sized hard stone).
The state of matter has a significant influence on its density. If you look at how the atomic particles are arranged in gaseous states, you’ll see that they are loosely packed as opposed to water that is more densely packed with its own set of atoms. Hence, air has less density as opposed to solids and liquids.
In terms of formula, the relationship of both mass and density is clearly seen. Mass is the product of density and volume (m = D x V) while density is ratio of mass per volume (D = m / V).
Summary:
1.Mass is how much matter is present in a particular object.
2.Density is how much mass is present per unit of volume.
3.Mass is expressed as m = D x V while density is D = m /V.