1. 1
   Two students each hold a bar magnet and investigate how the magnets interact when different poles are brought close together, without the magnets touching.

   (a)

   Two students each hold a bar magnet. Student A slowly brings the north pole of their magnet towards the north pole of student B's magnet. What do the students observe?

   [1 mark]

   • AThe magnets attract each other
   • BThe magnets repel each other
   • CNothing happens until the magnets touch
   • DThe magnets only interact if connected to a battery

   (b)

   The students then turn one magnet around so that the north pole of student A's magnet faces the south pole of student B's magnet. What describes the magnetic field between the magnets, and the type of force acting between them?

   [1 mark]

   • AA region around each magnet where a force acts on another magnet or magnetic material; the poles attract
   • BA region where only electric charges experience a force; the poles attract
   • CA region around each magnet where a force acts on another magnet or magnetic material; the poles repel
   • DThere is no field until the magnets are less than 1 mm apart

   (c)

   Explain why the students can observe the magnets attracting or repelling each other even though the magnets never touch.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   At a scrapyard, a large electromagnet is switched on and used to lift pieces of steel scrap out of a pile onto a crane. The crane then moves over a skip and the electromagnet is switched off, dropping the scrap into the skip.

   (a)

   While it is in the magnetic field of the electromagnet, what type of magnet does a piece of steel scrap become?

   [1 mark]

   • AA permanent magnet
   • BAn electromagnet
   • CIt does not become magnetic at all
   • DAn induced magnet

   (b)

   When the electromagnet is switched off above the skip and the piece of steel scrap falls away from the field, what happens to its magnetism?

   [1 mark]

   • AIt stays permanently magnetised at full strength
   • BIt becomes a permanent magnet only after falling
   • CIt loses its magnetism quickly
   • DIts magnetism increases once it leaves the field

   (c)

   Explain why the steel scrap is always attracted towards the electromagnet, and never repelled, no matter which way round a piece of scrap is oriented.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   Long before modern instruments existed, sailors relied on a magnetic compass to navigate the open sea. A teacher recreates a simpler version of this using a bar magnet and a small plotting compass on a sheet of paper, and also discusses why a compass needle always settles pointing in a particular direction wherever it is used on Earth.

   (a)

   Describe a method the teacher could use to plot the magnetic field pattern of the bar magnet using the plotting compass.

   [3 marks]

   (b)

   Explain how the field pattern around the bar magnet changes in strength and direction from pole to pole, and explain how the behaviour of an ordinary compass needle provides evidence that the Earth's core must be magnetic.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A materials testing laboratory is asked to determine whether an unidentified metal sample recovered from a factory is a permanent magnet or simply becomes magnetised in the presence of an external field. Technicians test the sample by bringing it close to a strong magnet, moving it further away, and then removing it from the field altogether to see how its magnetism changes.

   (a)

   Geologists study the Earth's magnetic field to understand more about the planet's structure. Using evidence from the behaviour of a magnetic compass, explain why scientists conclude that the Earth's core must be magnetic, and describe the pattern of the Earth's magnetic field.

   [6 marks]

   (b)

   Evaluate how the technicians in the laboratory could use the strength and behaviour of the sample's magnetism, as it is moved closer to, further from, and away from the strong magnet, to determine whether it is a permanent magnet or an induced magnet.

   [6 marks]

   Total for question 4: 12 marks

End of questions