If something seems light for its size (like a bag of cotton or pumice rock), then we say it has low density. Mass is the amount of matter in an object. Volume is how much space the object takes up.

It is always in three dimensions. To find the volume of an objects like a cube or a box, measure the length × width × height. If measured in centimeters, the answer will be in cubic centimeters (cm³).

The density of an object or substance is its mass divided by its volume: Density = Mass ÷ Volume. The units of density depend on the units used for mass and volume, but are usually: g/cm³ (if ...