what is density

Density is a measure of how much mass is contained in a given volume of a substance. It is commonly denoted by the symbol ρ or D, and it is defined as the mass divided by the volume of the substance. The formula for density is d = M/V, where d is the density, M is the mass, and V is the volume. Different materials have different densities, and it is a characteristic property of a substance, determined by the mass of its atoms, their size, and how they are arranged. Density can be expressed in various units such as kilograms per cubic meter (kg/m^3) or grams per cubic centimeter (g/cm^3). It is an intensive property, meaning it is independent of the amount of the substance. For example, a block of lead is denser than a block of gold, and a block of Styrofoam is less dense than a brick