# Explain what is meant by a field in physics, and describe how field lines are used to represent both the direction and strength of a gravitational field around a planet.

> 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 acts on an object (with the appropriate property)
2. Field lines show the direction of the force on a mass placed at that point
3. Field lines point towards the centre of the planet (for a gravitational field)
4. The spacing / separation of field lines shows the strength of the field
5. Field lines are closer together near the planet's surface and spread out further away, showing the field is stronger closer to the planet

## Key terms

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

## 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-what-is-meant-by-a-4d248c52) · Published by Druglandscape Ltd.