Question 1Warm-upFoundation
A block has a mass of 240 g and a volume of 30 cm³. Calculate its density in g/cm³.
ρ = m ÷ V.
Worked solution
- g/cm³
Answer: g/cm³
GCSE & IGCSE physics practice
Density questions and answers
Density is mass per unit volume: . In physics it's usually in kg/m³; for small objects g/cm³ is common, and 1 g/cm³ = 1000 kg/m³. Objects less dense than water (1 g/cm³) float. The questions include measuring the volume of an irregular object by displacement.
8 questions · Foundation tier · Every answer is checked as you type it, with a full worked solution. Updated .
Where density comes up
| GCSE (AQA) | Physics and Combined Science, Foundation and Higher. Recall ρ = m ÷ V (on AQA's list of equations to learn). Measuring density is a required practical. |
|---|---|
| Cambridge IGCSE (0625) | Core: define density as mass per unit volume and recall and use ρ = m ÷ V. Supplement: decide whether one liquid will float on another from density data. |
The method
- ρ = m ÷ V. Rearranged: m = ρ × V and V = m ÷ ρ.
- Keep units matching: g with cm³ gives g/cm³; kg with m³ gives kg/m³.
- 1 g/cm³ = 1000 kg/m³.
- Irregular object: volume = rise in water level in a measuring cylinder (displacement).
Density questions
Try each one before looking at the hint. If you're stuck, the AI tutor can talk you through it step by step.
Warm-up
Question 2Warm-upFoundation
A 2 m³ block of concrete has a mass of 4800 kg. Calculate its density.
ρ = m ÷ V.
Worked solution
- kg/m³
Answer: kg/m³
Exam-style
Question 3Exam-styleFoundation
Gold has a density of 19.3 g/cm³. What is the mass of a 5 cm³ gold bar?
m = ρ × V.
Worked solution
- g
Answer: g
Question 4Exam-styleFoundation
Oil has a density of 800 kg/m³. What volume does 2000 kg of oil take up?
V = m ÷ ρ.
Worked solution
- m³
Answer: m³
Question 5Exam-styleFoundation
A stone is lowered into a measuring cylinder. The water level rises from 50 cm³ to 70 cm³. The stone's mass is 54 g. Calculate its density.
Volume = rise in water level.
Worked solution
- cm³
- g/cm³
Answer: g/cm³
Question 6Exam-styleFoundation
A cube has sides of 2 cm and a mass of 64 g. Calculate its density.
Volume of a cube = side³.
Worked solution
- cm³
- g/cm³
Answer: g/cm³
Challenge
Question 7ChallengeFoundation
Convert a density of 2.7 g/cm³ into kg/m³.
1 g/cm³ = 1000 kg/m³.
Worked solution
- kg/m³
Answer: kg/m³
Question 8ChallengeFoundation
A 1.2 kg block measures 10 cm × 10 cm × 15 cm. Will it float in water (density 1 g/cm³)?
Work in grams and cm³.
Worked solution
- cm³ and g
- g/cm³ g/cm³, so it floats
Answer: Yes: g/cm³, which is less than water
Common mistakes
- Dividing volume by mass.
- Mixing g with m³ or kg with cm³.
- Using the final water level instead of the rise.
Stuck on one of these?
The TutorAura AI tutor works through it with you step by step, with the reason for each step, then gives you one like it to try. It checks your working too.
Try the AI tutor freeMore physics questions
Sources
The questions are our own. The “where it comes up” notes are from each board's published specification, checked on 27 October 2026:
Practise physics with your own AI tutor
Questions at your level, help when you're stuck, and a plan for your exams. Free for 3 days, no card needed.