Describe the magnetic field around a bar magnet. In your answer, refer to the direction of the field lines, how the spacing of the field lines changes, and the region where the magnetic field is strongest.
Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).
Model answer (5 marks)
The magnetic field lines of a bar magnet run from the north pole to the south pole outside the magnet. They never cross each other. The lines are most densely packed, i.e. closest together, near the poles, and spread further apart as the distance from the magnet increases. Consequently the magnetic field is strongest at the poles where the field lines are most closely spaced.
Examiner tips
- Use the phrase "run from north to south" to show direction. Mention that lines never cross. State that lines are closest at the poles and spread out with distance. Link the strongest field to the closest spacing.
- Include all five points in a logical order – direction, non‑crossing, density at poles, spreading, field strength.
Mark scheme (5 marks)
- Magnetic field lines go from north pole to south pole (outside the magnet)
- Field lines never cross each other
- Field lines are closest together (most densely packed) near the poles
- Field lines spread further apart as distance from the magnet increases
- The magnetic field is strongest at the poles / where the field lines are most closely spaced
Key terms in this question
Related
- All Eduqas A-Level Physics revision notes →
- How to answer a "Describe" question →
- Decode the mark scheme abbreviations →
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