Free Density questions for IGCSE Physics (0625), part of Motion, forces & energy. Each question has the answer and the marking points an examiner would look for.
Generate a full Density worksheet →All Motion, forces & energy questionsAn empty bottle has a mass of 60 g. When completely full of oil (density 0.80 g/cm³) its total mass is 220 g.
What is the total mass of the bottle when it is completely full of salt solution of density 1.2 g/cm³?
Answer: B
Which statement about mass and weight is correct?
Answer: B
A student has a rectangular metal block measuring 4.0 cm × 5.0 cm × 2.0 cm. Its mass is 452.0 g.
Calculate the volume of the block.
Calculate the density of the metal.
Use Table 3.1 to identify the metal.
| Metal | Density / g/cm³ |
|---|---|
| aluminium | 2.7 |
| titanium | 4.5 |
| iron | 7.9 |
| copper | 8.9 |
| lead | 11.3 |
Calculate the weight of the block. (g = 9.8 N/kg)
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | 40 cm³ 40 B1 | 1 |
| (b) | 11.3 g/cm³ ρ = m ÷ V C1 11.3 A1 | 2 |
| (c) | lead lead (ecf from (b)) B1 | 1 |
| (d) | 4.43 N W = mg with m in kg C1 4.43 A1 | 2 |
A student finds the density of a small irregularly shaped stone. Fig. 4.1 shows the measuring cylinder before and after the stone is lowered into the water.
Describe how the student can find the volume of the stone using a measuring cylinder and water.
Use Fig. 4.1 to find the volume of the stone.
The stone has a mass of 54.0 g. Calculate its density in kg/m³.
Explain whether the stone floats in sea water of density 1030 kg/m³.
The mass of the stone is measured on the Moon. State and explain whether its mass and its weight change.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | record initial volume; lower stone in fully; volume = rise in level partly fill the cylinder and read the volume B1 lower the stone in so it is fully submerged B1 volume of stone = new reading − initial reading B1 | 3 |
| (b) | 20 cm³ 70 − 50 = 20 cm³ B1 | 1 |
| (c) | 2700 kg/m³ ρ = m/V = 54.0/20 = 2.70 g/cm³ C1 × 1000 C1 2700 kg/m³ A1 | 3 |
| (d) | sinks: denser than sea water sinks because its density is greater than that of sea water B1 | 1 |
| (e) | mass same; weight smaller because g is smaller mass is unchanged (same amount of matter) B1 weight is less because the gravitational field strength is smaller B1 | 2 |
A student finds the density of cooking oil.
Describe how she measures the mass and the volume of the oil.
50 cm³ of oil has a mass of 46 g. Calculate the density in g/cm³.
The oil is poured onto water. State and explain what happens.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | balance with empty and full cylinder; read volume weigh an empty measuring cylinder B1 add oil, read the volume at eye level (bottom of meniscus) B1 weigh again and subtract B1 | 3 |
| (b) | 0.92 g/cm³ ρ = m ÷ V = 46 ÷ 50 C1 0.92 g/cm³ A1 | 2 |
| (c) | floats; less dense the oil floats because it is less dense than water B1 | 1 |
A ship made of steel floats on water even though steel is much denser than water.
Explain how the ship can float.
Explain why the ship floats lower in fresh water than in sea water.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | average density less than water the ship contains a lot of air B1 so its average density is less than that of water B1 | 2 |
| (b) | fresh water less dense fresh water is less dense than sea water B1 so more must be displaced to support the same weight B1 | 2 |
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Meet Riyaz →Original Cambridge-style practice questions written for mentorriyaz.in. These are not Cambridge past paper questions, and this site is not affiliated with or endorsed by Cambridge University Press & Assessment. Updated 2026-11-04. Paper generator · mentorriyaz.in