Which unit is stated for density in the material?

Which unit is stated for density in the material?

• A. pounds mass/feet cubed
• B. kilograms per cubic meter
• C. pounds force per cubic foot
• D. grams per liter

Answer: (A)

Density is mass per unit volume, so the unit should express mass divided by volume. In US customary engineering practice, that is pounds mass per cubic foot (lbm/ft^3), which directly measures how much matter is contained in a given volume. The alternative of pounds force per cubic foot is weight density—weight per volume—not mass per volume. Grams per liter is a metric density unit (1 g/L equals 1 kg/m^3), but the material here uses the English-engineering convention. So the density unit stated in the material is pounds mass per cubic foot.

Density is mass per unit volume, so the unit should express mass divided by volume. In US customary engineering practice, that is pounds mass per cubic foot (lbm/ft^3), which directly measures how much matter is contained in a given volume. The alternative of pounds force per cubic foot is weight density—weight per volume—not mass per volume. Grams per liter is a metric density unit (1 g/L equals 1 kg/m^3), but the material here uses the English-engineering convention. So the density unit stated in the material is pounds mass per cubic foot.