Density compares two measurable properties of a sample of matter. Which statement defines it?
- The weight per unit of surface area
- The volume per unit of mass
- The mass per unit of volume
- The force per unit of area
Show answer and solution
Correct answer: C. The mass per unit of volume
1. Density is defined as the mass of a substance divided by the volume that mass occupies.
2. In symbols this is written as mass divided by volume, so density is the mass per unit of volume.
3. Volume per unit of mass is the reciprocal of density, not density itself.
4. Force per unit of area is the definition of pressure, and weight per unit of surface area is not a standard quantity here.
_Source: OpenStax College Physics (CC BY 4.0), Ch 11 "Fluid Statics", section 11.2 Density_