# A student is asked to estimate the density of a human body. Explain how the student could arrive at a reasonable estimate, including suitable estimated values for the quantities needed.

> AQA A-Level Physics (7408) — 3.1.3 Estimation of Physical Quantities · Explain · 5 marks

## Mark scheme (5 marks)

1. Recognises that density = mass / volume (or states both mass and volume are needed)
2. States a reasonable estimated mass for a human body (50–90 kg accepted)
3. Describes a method to estimate the volume of a human body (e.g. modelling the body as simple geometric shapes such as cylinders or cuboids, or using water displacement)
4. States a reasonable estimated volume for a human body (0.05–0.09 m³ accepted, or equivalent e.g. 50–90 litres / 50 000–90 000 cm³)
5. Arrives at a density estimate close to 1000 kg/m³ (accept 700–1100 kg/m³) and/or notes this is close to the density of water

## Key terms

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

## Related

- [Revision notes for AQA A-Level Physics (7408)](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-is-asked-to-estimate-f195d6a0) · Published by Druglandscape Ltd.