Calcolatore Densita

What is density?

Density is the amount of mass contained in a given volume. It's an intensive property of matter — it doesn't depend on how much of the material you have, only its nature. Water has a density of 1,000 kg/m³ at 4°C; iron, 7,874 kg/m³; air, just 1.225 kg/m³ at sea level. Density explains why ice floats on water, why oil and water don't mix, and how Archimedes' principle works.

Density formula

ρ = m / V

Where:

• ρ (rho) = density (kg/m³, g/cm³, kg/L…)
• m = mass (kg, g)
• V = volume (m³, cm³, L)

The three rearranged forms: m = ρ × V and V = m / ρ

Step-by-step example

An aluminum bar weighs 540 g and has a volume of 200 cm³. Is it really aluminum?

1. ρ = m / V = 540 / 200 = 2.7 g/cm³
2. Pure aluminum density: 2.70 g/cm³ ✓
3. If density were higher (≈2.9), it could indicate an alloy with zinc or other metals.

Densities of common materials

• Air (20°C): 1.204 kg/m³
• Water (4°C): 1,000 kg/m³ = 1 g/cm³
• Pine wood (dry): 500–600 kg/m³
• Concrete: 2,200–2,400 kg/m³
• Aluminum: 2,700 kg/m³
• Iron/steel: 7,850–7,900 kg/m³
• Lead: 11,340 kg/m³
• Gold: 19,300 kg/m³

Applications of density

• Material identification: Verify whether a metal part is the correct alloy or detect adulteration.
• Buoyancy (Archimedes): An object floats if its average density is less than the surrounding fluid's density.
• Engineering and construction: Calculate the weight of a structure knowing its volume and material.
• Geology: Rock and mineral density helps identify them and model Earth's interior.
• Food and beverage: Must density (1.04–1.10 g/cm³) indicates sugar content in wine and beer production.