# A student uses a plotting compass to investigate the magnetic field of the Earth. The student notices that the compass needle always points in the same direction when placed on a flat surface away from any magnets or iron objects. Explain what this tells us about the Earth, and describe how the magnetic field of the Earth compares to that of a bar magnet.

> Eduqas A-Level Physics — 4.4 Magnetic fields · Explain · 5 marks

## Mark scheme (5 marks)

1. The Earth behaves as / acts like a magnet (has a magnetic field)
2. The compass needle points towards the Earth's geographic north (pole) / the compass aligns with the Earth's magnetic field
3. The Earth's magnetic field has field lines that (travel from south to north / enter at the geographic north pole / exit at the geographic south pole) OR the geographic north pole is near the Earth's magnetic south pole
4. The Earth's magnetic field is similar in shape to that of a bar magnet / has field lines that curve from one pole to the other
5. The Earth's magnetic field extends into space / is much weaker than a bar magnet's field OR the Earth's field is large-scale / spread over a much greater area than a bar magnet

## Key terms

- [magnetic field](https://www.gradenine.co.uk/glossary/magnetic-field)
- [plotting compass](https://www.gradenine.co.uk/glossary/plotting-compass)

## Related

- [Revision notes for Eduqas A-Level Physics](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-uses-a-plotting-compass-ea8331e0) · Published by Druglandscape Ltd.