AQA GCSE Combined Science: Trilogy Physics Paper 2 (Higher), 2018: Question 2

✅ Correct answer

Tick the 1st box.

The first diagram shows magnetic field lines correctly around the bar magnet.

Mark scheme: 1st box ticked = 1 mark

💡 Key knowledge

• Magnetic field lines go from N to S outside the magnet.
• Field lines are curved and form closed loops.
• They are closest together near the poles, where the field is strongest.

🧠 Exam technique

• Look for arrows pointing away from N and towards S.
• Check the overall shape: field lines should not cross.
• For a one-mark multiple-choice question, you only need the correct box — no explanation needed.

❌ Common errors

• Choosing a diagram where the arrows go the wrong way.
• Thinking the field lines go in straight lines out of the poles.
• Ticking a diagram with field lines that do not correctly curve around the magnet.

✅ Correct answer

A permanent magnet can be used to test each block:

• Aluminium is not attracted / has no effect.
• Iron is attracted to the permanent magnet.
• The other permanent magnet can be repelled by the magnet.

Mark scheme points: one mark each for aluminium, iron, and the permanent magnet.

💡 Key knowledge

• Iron is magnetic, so it is attracted to a magnet.
• Aluminium is not magnetic at GCSE level, so it will not be attracted.
• Like poles repel, so a permanent magnet can repel another permanent magnet.

🧠 Exam technique

• Use the words in the mark scheme: no effect, attracted, and repelled.
• Make it clear which material matches which test result.
• Short, precise statements score better than vague descriptions.

❌ Common errors

• Saying aluminium is attracted — this loses the mark.
• Saying the permanent magnet is attracted instead of repelled.
• Not separating the three materials clearly, so the examiner cannot award all three marks.

✅ Correct answer

A high-mark answer should include these linked points:

• Switching on the circuit allows current to flow through the coil.
• The current in the coil produces a magnetic field.
• The iron core becomes magnetised, so the crane becomes an electromagnet.
• The electromagnet attracts the blocks made from magnetic materials.
• The crane can move the blocks while they are attached.
• Switching off the current turns off the electromagnet, so the blocks are released.

Mark scheme idea: the best answers describe the whole sequence clearly and logically.

💡 Key knowledge

• An electromagnet is a magnet made by electricity.
• It only works when there is current in the coil.
• A coil around an iron core makes a stronger magnet than a coil alone.
• When the current stops, the magnetism stops or becomes much weaker.

🧠 Exam technique

• Write in cause-and-effect order: current → magnetic field → magnetised core → attraction → movement → switch off → release.
• Top-level answers link each idea, rather than listing random facts.
• Use the context of the picture: the crane picks up and moves blocks made of magnetic material.

❌ Common errors

• Saying the electromagnet works because it has “metal” in it — too vague.
• Forgetting the switch off part, which is important for releasing the blocks.
• Not mentioning current, which is essential for the electromagnet.
• Saying all materials are picked up — the question says the blocks are made from magnetic materials.

Magnetic field around a bar magnet

Outside the magnet, field lines go from N to S.

Testing the blocks

Aluminium is not attracted, iron is attracted, and a permanent magnet can be repelled.

Electromagnet in the crane

Current in the coil makes a magnetic field, magnetising the iron core so it can attract and then release the blocks when switched off.