# A student places a solid rubber bung into a measuring cylinder containing water. The water level rises from 40 cm³ to 55 cm³. The student then measures the mass of the rubber bung using a balance and finds it to be 22.5 g. Explain how the student uses these measurements to determine the density of rubber, and state the value of the density.

> Cambridge International IGCSE Physics (0625) — 1.4 Density · Explain · 4 marks

## Mark scheme (4 marks)

1. Volume of rubber bung is found by subtracting the initial water level from the final water level (55 − 40 = 15 cm³)
2. Density is calculated using density = mass ÷ volume
3. Correct substitution of values: density = 22.5 ÷ 15
4. Correct density value of 1.5 g/cm³ (or equivalent 1500 kg/m³)

## Key terms

- [density](https://www.gradenine.co.uk/glossary/density)
- [mass](https://www.gradenine.co.uk/glossary/mass)

## Related

- [Revision notes for Cambridge International IGCSE Physics (0625)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/a-student-places-a-solid-rubber-25b21a68) · Published by Druglandscape Ltd.