Question

what is density and its units

Answer 1

Density of a substance is defined as mass per unit volume.
Density = Mass
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volume
SI unit of density is kg/meter cube

Answer 2

The density of more precisely , the volumetric mass density of a substance is the mass per unit volum.The symbol most often used for Density is p . although the Latin letter D can also be used .
Mathematically , density is defined as weight per unit volume.