This required practical covers Required Practical: Measuring Density 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 4 of 13 in this topic. Revise both the method and the reason for each step, because practical questions often test understanding rather than pure recall.
🔬 Required Practical: Measuring Density
For REGULAR shapes (cube, cuboid, cylinder):
- Measure mass using a balance (kg or g)
- Measure dimensions with ruler/vernier calipers
- Calculate volume using geometry:
• Cuboid: V = length × width × height
• Cylinder: V = πr²h - Calculate density: ρ = m / V
For IRREGULAR shapes (stones, random objects):
- Measure mass using a balance
- Use displacement method:
• Fill measuring cylinder partially with water
• Record initial volume (V₁)
• Lower object into water (fully submerged)
• Record new volume (V₂) - Volume of object = V₂ - V₁
- Calculate density: ρ = m / V
Sources of error:
- Parallax error when reading water level
- Air bubbles on irregular objects
- Objects that absorb water
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
What is density?
Mass per unit volume of a substance. How much 'stuff' is packed into a given space.
Density equation
ρ = m/V