Density of Regular Solids - AQA Practical

AQA GCSE Physics Density required practical: deducing density of a regular solid, a cube, through converting units.‍ ‍Combined & Triple Science.

---

A student estimates that a cube has side lengths 3 cm and a mass of 250 g.

Plan a valid method to verify these measurements and determine its density in kg/m³.

[6 marks]

---

1. Measure & Convert

• How do we obtain the mass?

  • Place the cube on a balance and record its mass in grams (250 g).

• How do we convert from g to kg?

  • Divide the mass in grams by 1000.

  • 250 ÷ 1000 = 0.25 kg

• How do we find the volume?

  • Measure the length, width and height of the cube using a ruler.

  • Calculate volume = length × width × height.

  • 3 × 3 × 3 = 27 cm³

• How do we convert from cm³ to m³?

  • Divide the volume in cm³ by 100³ (1,000,000), since the conversion factor applies to all three dimensions.

  • 27 ÷ 1,000,000 = 0.000027 m³

Record Readings

Calculate

• How do we calculate the density?

  • Divide the mass in kilograms by the volume in cubic metres.

  • Density = mass ÷ volume

  • 0.25 ÷ 0.000027 = 9260 kg/m³ (3 s.f.)

Challenge:

• How do we calculate density of a sphere?

  1. Measure the mass of the sphere using a balance.

  2. Measure its diameter using a ruler and divide by 2 to obtain the radius.

  3. Calculate the volume using V = ⁴⁄₃πr³.

  4. Calculate density = mass ÷ volume.

  Convert the measurements to kg and m³ to obtain density in kg/m³.

Continue Revising Paper 1

Need help improving your GCSE Physics grade?

These visuals are created by our experienced GCSE tutors.