# Explain how the concept of a field is used to describe the interaction between two masses separated by empty space, and describe what happens to the field strength as the distance between the masses increases.

> AQA A-Level Physics (7408) — 3.7.1 Fields · Explain · 5 marks

## Mark scheme (5 marks)

1. A field is a region of space where a force is experienced (by an appropriate object)
2. A gravitational field exists around any object with mass
3. The field allows us to describe the force on one mass (or object) without the masses physically touching / explains action at a distance
4. As the distance between the masses increases, the gravitational field strength decreases
5. Field lines spread further apart / become less dense at greater distances, showing the field is weaker

## Key terms

- [field](https://www.gradenine.co.uk/glossary/field)
- [field strength](https://www.gradenine.co.uk/glossary/field-strength)

## 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/explain-how-the-concept-of-a-a216c229) · Published by Druglandscape Ltd.