This key facts covers Key Density Values within Density for GCSE Physics. Revise Density in Particle Model for GCSE Physics with 13 exam-style questions and 30 flashcards. This topic shows up very often in GCSE exams, so students should be able to explain it clearly, not just recognise the term. It is section 3 of 13 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
📚 Key Density Values
| Material | Density (kg/m³) | Density (g/cm³) |
|---|---|---|
| Air | 1.2 | 0.0012 |
| Ice | 920 | 0.92 |
| Water | 1000 | 1.0 |
| Aluminium | 2700 | 2.7 |
| Steel/Iron | 7800 | 7.8 |
| Copper | 8900 | 8.9 |
| Gold | 19,300 | 19.3 |
The water benchmark:
- Objects with density < 1000 kg/m³ (or < 1 g/cm³) FLOAT in water
- Objects with density > 1000 kg/m³ (or > 1 g/cm³) SINK in water
- Ice floats because it's LESS dense than liquid water (unusual property!)
Two common units:
- kg/m³ — SI unit, used in most calculations
- g/cm³ — often used for small objects; easier numbers
- Conversion: 1 g/cm³ = 1000 kg/m³
Practice questions for Density
What is the correct equation for density?
Explain why gases have a much lower density than solids, using ideas about particles.
Quick recall flashcards
Density equation
ρ = m/V
What is density?
Mass per unit volume of a substance. How much 'stuff' is packed into a given space.