AQA · GCSE · Combined Science
Course version: 8464 · Version from Sept 2018
The strength of the magnetic field depends on the distance from the…
Full specification wording
Magnetic fields: The strength of the magnetic field depends on the distance from the magnet. The field is strongest at the poles of the magnet.
A magnetic field is the region around a magnet where a magnetic force can be detected.
Checked against the AQA 8464 specification (opens in a new tab) on .
- Point 3 of 8
Study notes
From the checked teaching notes for this specification point.
The idea
A magnetic field is the region around a magnet where a magnetic force can be detected. Its strength is not uniform: it is greatest close to the magnet and weaker further away. Around a bar magnet, the field is strongest at the north and south poles, where the field lines are most concentrated, and weaker at the sides and with increasing distance. Field lines are drawn with arrows pointing from north to south outside the magnet, and the spacing of the lines shows strength: closely spaced lines mean a strong field, widely spaced lines mean a weak field. A plotting compass placed near a magnet aligns with the field at that point, so moving the compass traces the field pattern and shows how strength falls with distance.
What earns the marks
- State that magnetic field strength decreases as distance from the magnet increases.
- Identify the poles as the regions where the magnetic field is strongest.
- Interpret field-line diagrams, using line spacing to judge relative field strength.
- Describe how a plotting compass can be used to trace a magnetic field pattern around a magnet.
- Explain that field lines point from north to south outside the magnet and are most concentrated at the poles.
Common mistakes and how to put them right
Assuming the field is the same strength everywhere around a magnet.
Put it right: The field is strongest at the poles and weakens with distance.
Thinking that field lines crossing mean a stronger field.
Put it right: Field lines never cross; strength is shown by how closely spaced they are.
Drawing field lines with arrows pointing from south to north outside the magnet.
Put it right: Outside the magnet, arrows point from north to south.
Exam tips
- When sketching a field, draw lines closer together near the poles and further apart away from the magnet.
- Use the spacing of field lines as evidence when asked to compare field strength at two points.
- Describe the plotting compass method step by step, including marking the compass direction and joining the marks to show a field line.
Try the lesson
The start of the Magnetic fields: The strength of the magnetic field depends on the distance from the magnet. The field is strongest at the poles of the magnet. lesson, made from checked teaching notes for this specification point.
Have a go first
At which part of a bar magnet is the magnetic field strongest?
Listen
A magnetic field is the region around a magnet where a magnetic force can be detected. Its strength is not uniform: it is greatest close to the magnet and weaker further away. Around a bar magnet, the field is strongest at the north and south poles, where the field lines are most concentrated, and weaker at the sides and with increasing distance. Field lines are drawn with arrows pointing from north to south outside the magnet, and the spacing of the lines shows strength: closely spaced lines mean a strong field, widely spaced lines mean a weak field. A plotting compass placed near a magnet aligns with the field at that point, so moving the compass traces the field pattern and shows how strength falls with distance. A strong answer earns marks for these points. State that magnetic field strength decreases as distance from the magnet increases. Identify the poles as the regions where the magnetic field is strongest. Interpret field-line diagrams, using line spacing to judge relative field strength. Describe how a plotting compass can be used to trace a magnetic field pattern around a magnet. A common slip: Assuming the field is the same strength everywhere around a magnet. Instead, the field is strongest at the poles and weakens with distance. Exam tip: When sketching a field, draw lines closer together near the poles and further apart away from the magnet.
See it
Label the diagram
Some boxes have lost their names. Pick the right name for each number.
1Box 1
2Box 2
3Box 3
There is more to this lesson
The full lesson goes on to check your understanding and help you earn the marks. Create a free account to carry on, with your progress saved.
A week of Premium from your first lesson · Then the free plan continues · No card, no charge
Test your understanding of Magnetic fields: The strength of the magnetic field depends on the distance from the magnet. The field is strongest at the poles of the magnet.
Active recall beats re-reading. Take an instant quiz now to test what you’ve learned and lock it into long-term memory.
A week of Premium from your first lesson · Then the free plan continues · No card, no charge