Table of Contents
How to use this answer sheet:
- Check your answers against the correct answers shown in green
- Read the explanations to understand why each answer is correct
- Review the revision notes for important concepts
- Use the key points to remember important information
SECTION A: MULTIPLE CHOICE ANSWERS [15 marks] #
1. Which statement about magnetic poles is correct?
Answer: C – Like poles repel each other
Why this answer is correct:
Magnetic poles follow a simple rule: like poles (north-north or south-south) repel each other, while unlike poles (north-south) attract each other. This is a fundamental law of magnetism.
Magnetic poles follow a simple rule: like poles (north-north or south-south) repel each other, while unlike poles (north-south) attract each other. This is a fundamental law of magnetism.
Remember: Opposites attract, likes repel – just like with electric charges.
2. A magnet is brought near an iron nail. What happens to the nail?
Answer: B – The nail is attracted to both poles of the magnet
Why this answer is correct:
Iron is a magnetic material. When a magnet approaches an unmagnetised iron nail, the nail becomes magnetised through induced magnetism. The induced pole nearest to the magnet is always the opposite pole, so attraction always occurs regardless of which pole of the magnet is used.
Iron is a magnetic material. When a magnet approaches an unmagnetised iron nail, the nail becomes magnetised through induced magnetism. The induced pole nearest to the magnet is always the opposite pole, so attraction always occurs regardless of which pole of the magnet is used.
Important: Magnets always attract magnetic materials (iron, nickel, cobalt, steel) – they never repel them.
3. Which of the following materials is magnetic?
Answer: C – Nickel
Why this answer is correct:
Only a few materials are magnetic. The main magnetic materials at room temperature are iron, nickel, cobalt, and steel (which contains iron). Aluminum, copper, and plastic are all non-magnetic materials.
Only a few materials are magnetic. The main magnetic materials at room temperature are iron, nickel, cobalt, and steel (which contains iron). Aluminum, copper, and plastic are all non-magnetic materials.
Remember the magnetic materials: Iron, Nickel, Cobalt, and Steel
4. What is induced magnetism?
Answer: B – When a magnetic material becomes a temporary magnet near a permanent magnet
Why this answer is correct:
Induced magnetism occurs when an unmagnetised magnetic material (like an iron nail) is placed in a magnetic field. The magnetic field causes the domains in the material to line up temporarily, making it act as a magnet. When the permanent magnet is removed, the material loses its magnetism.
Induced magnetism occurs when an unmagnetised magnetic material (like an iron nail) is placed in a magnetic field. The magnetic field causes the domains in the material to line up temporarily, making it act as a magnet. When the permanent magnet is removed, the material loses its magnetism.
5. A bar magnet is broken in half. What is the result?
Answer: C – Each piece becomes a magnet with its own north and south poles
Why this answer is correct:
You can never isolate a single magnetic pole. When you break a magnet, each piece becomes a complete magnet with both north and south poles. This is because magnetism comes from the alignment of tiny magnetic domains throughout the material, not from having separate “north material” and “south material.”
You can never isolate a single magnetic pole. When you break a magnet, each piece becomes a complete magnet with both north and south poles. This is because magnetism comes from the alignment of tiny magnetic domains throughout the material, not from having separate “north material” and “south material.”
Important rule: Every magnet must have both a north pole and a south pole. Single poles (monopoles) do not exist.
6. Which material is used to make temporary magnets?
Answer: B – Soft iron
Why this answer is correct:
Soft iron is easy to magnetise and easy to demagnetise, making it perfect for temporary magnets. It becomes magnetic when placed in a magnetic field but loses its magnetism quickly when the field is removed. This property makes it ideal for electromagnets.
Soft iron is easy to magnetise and easy to demagnetise, making it perfect for temporary magnets. It becomes magnetic when placed in a magnetic field but loses its magnetism quickly when the field is removed. This property makes it ideal for electromagnets.
7. Which statement about steel magnets is correct?
Answer: B – Steel is difficult to magnetize but keeps its magnetism for a long time
Why this answer is correct:
Steel is a permanent magnet material. It requires a strong magnetic field and time to become magnetised, but once magnetised, it retains its magnetism for many years. The carbon atoms in steel make it harder for magnetic domains to move, which is why it’s difficult to magnetise and demagnetise.
Steel is a permanent magnet material. It requires a strong magnetic field and time to become magnetised, but once magnetised, it retains its magnetism for many years. The carbon atoms in steel make it harder for magnetic domains to move, which is why it’s difficult to magnetise and demagnetise.
Comparison:
• Soft iron = temporary magnet (easy in, easy out)
• Steel = permanent magnet (difficult in, difficult out)
• Soft iron = temporary magnet (easy in, easy out)
• Steel = permanent magnet (difficult in, difficult out)
8. A magnetic field is best defined as
Answer: B – a region where a magnetic pole experiences a force
Why this answer is correct:
A magnetic field is the region around a magnet where magnetic forces can be detected. If you place a magnetic pole (like the north pole of a small compass) in this region, it will experience a force. The field extends through space around the magnet, getting weaker with distance.
A magnetic field is the region around a magnet where magnetic forces can be detected. If you place a magnetic pole (like the north pole of a small compass) in this region, it will experience a force. The field extends through space around the magnet, getting weaker with distance.
9. The direction of a magnetic field at a point is
Answer: B – the direction a north pole would move at that point
Why this answer is correct:
By convention, the direction of a magnetic field at any point is defined as the direction that a free north pole would move if placed at that point. This is why magnetic field lines have arrows pointing from north to south – showing the direction a north pole would be pushed.
By convention, the direction of a magnetic field at any point is defined as the direction that a free north pole would move if placed at that point. This is why magnetic field lines have arrows pointing from north to south – showing the direction a north pole would be pushed.
Remember: Field direction = direction of force on a north pole
10. Magnetic field lines around a bar magnet
Answer: B – go from north pole to south pole outside the magnet
Why this answer is correct:
Magnetic field lines always emerge from the north pole and enter the south pole when outside the magnet. They then continue through the magnet from south to north, forming complete closed loops. The lines curve around the magnet and never cross each other.
Magnetic field lines always emerge from the north pole and enter the south pole when outside the magnet. They then continue through the magnet from south to north, forming complete closed loops. The lines curve around the magnet and never cross each other.
11. Iron filings are sprinkled around a magnet. Why do they form a pattern?
Answer: A – Each filing becomes magnetized and lines up with the magnetic field
Why this answer is correct:
Each tiny iron filing becomes a temporary magnet through induced magnetism. The north pole of one filing attracts the south pole of the next filing, causing them to arrange themselves in chains along the magnetic field lines. This creates a visible pattern showing the shape of the invisible magnetic field.
Each tiny iron filing becomes a temporary magnet through induced magnetism. The north pole of one filing attracts the south pole of the next filing, causing them to arrange themselves in chains along the magnetic field lines. This creates a visible pattern showing the shape of the invisible magnetic field.
12. Where is the magnetic field around a bar magnet strongest?
Answer: B – At the poles of the magnet
Why this answer is correct:
The magnetic field is strongest at the poles of a magnet, where the magnetic field lines are closest together. The field gets weaker as you move away from the poles. At the center of the magnet, the field is actually quite weak.
The magnetic field is strongest at the poles of a magnet, where the magnetic field lines are closest together. The field gets weaker as you move away from the poles. At the center of the magnet, the field is actually quite weak.
Remember: Closer field lines = stronger field. Field lines are closest at the poles.
13. Which of these is a use of permanent magnets?
Answer: C – Compasses for navigation
Why this answer is correct:
Compasses use permanent magnets because they need to stay magnetic without any power supply. The magnetized needle aligns with Earth’s magnetic field to show direction. All the other options (A, B, D) use electromagnets because they need to be switched on and off with electricity.
Compasses use permanent magnets because they need to stay magnetic without any power supply. The magnetized needle aligns with Earth’s magnetic field to show direction. All the other options (A, B, D) use electromagnets because they need to be switched on and off with electricity.
14. Why is soft iron used as the core of an electromagnet?
Answer: B – It magnetizes easily when current flows and loses magnetism when current stops
Why this answer is correct:
Soft iron is perfect for electromagnets because it becomes magnetic quickly when electricity flows through the coil around it, and loses its magnetism quickly when the electricity stops. This allows the electromagnet to be switched on and off. If steel was used, it would stay magnetic even after the current was switched off.
Soft iron is perfect for electromagnets because it becomes magnetic quickly when electricity flows through the coil around it, and loses its magnetism quickly when the electricity stops. This allows the electromagnet to be switched on and off. If steel was used, it would stay magnetic even after the current was switched off.
15. Magnetic forces between two magnets are caused by
Answer: B – interactions between their magnetic fields
Why this answer is correct:
Magnetic forces work at a distance through magnetic fields. When two magnets come close together, their magnetic fields overlap and interact. This interaction between the fields creates the forces of attraction or repulsion that we observe. The magnets do not need to touch for forces to act.
Magnetic forces work at a distance through magnetic fields. When two magnets come close together, their magnetic fields overlap and interact. This interaction between the fields creates the forces of attraction or repulsion that we observe. The magnets do not need to touch for forces to act.
Important: This is a supplement topic – magnetic forces are due to field interactions, not direct contact.
SECTION B: WRITTEN RESPONSE ANSWERS [60 marks] #
1. Two bar magnets are placed near each other. The north pole of the first magnet faces the north pole of the second magnet.
(a) State whether the magnets will attract or repel each other. [1 mark]
(b) Explain your answer to part (a). [2 marks]
(c) State what would happen if the second magnet was turned around so that its south pole faced the north pole of the first magnet. [1 mark]
(d) Explain your answer to part (c). [1 mark]
(a)
Repel
Mark scheme: 1 mark for “repel”
(b)
The magnets will repel each other because like poles (north-north) repel. When two north poles face each other, they push away from each other due to the interaction between their magnetic fields.
Mark scheme: 1 mark for stating “like poles repel”, 1 mark for identifying that both are north poles
(c)
The magnets would attract each other
Mark scheme: 1 mark for “attract”
(d)
Unlike poles (north-south) attract each other, so the magnets would pull toward each other.
Mark scheme: 1 mark for explaining unlike poles attract
2. A student has three materials: an iron nail, a copper wire, and a steel paper clip.
(a) State which of these materials are magnetic. [2 marks]
(b) Describe a simple test the student could do to check if a material is magnetic. [2 marks]
(c) The student brings a bar magnet close to the iron nail. Explain what happens to the iron nail and why. [3 marks]
(a)
Iron nail and steel paper clip are magnetic
(Copper wire is not magnetic)
(Copper wire is not magnetic)
Mark scheme: 1 mark for iron nail, 1 mark for steel paper clip
(b)
Bring a magnet close to each material. If the material is pulled toward the magnet (attracted), then it is magnetic. If nothing happens, the material is non-magnetic.
Mark scheme: 1 mark for bringing magnet near material, 1 mark for observing attraction
(c)
The iron nail is attracted to the magnet. This happens because the iron nail becomes magnetised through induced magnetism. The magnetic field from the bar magnet causes the domains in the iron nail to line up, temporarily making it a magnet. The end of the nail nearest to the magnet becomes the opposite pole, causing attraction.
Mark scheme: 1 mark for stating nail is attracted, 1 mark for mentioning induced magnetism, 1 mark for explaining domains line up or opposite pole forms
3. The table below compares soft iron and steel.
| Property | Soft Iron | Steel |
|---|---|---|
| Ease of magnetization | _______________ | Difficult |
| Ease of demagnetization | Very easy | _______________ |
| Type of magnet formed | _______________ | Permanent magnet |
| How long magnetism lasts | Very short time | _______________ |
(a) Complete the table by filling in the empty spaces. [4 marks]
(b) Explain why soft iron is used to make the core of an electromagnet rather than steel. [2 marks]
(a)
| Property | Soft Iron | Steel |
|---|---|---|
| Ease of magnetization | Very easy / Easy | Difficult |
| Ease of demagnetization | Very easy | Difficult / Very difficult |
| Type of magnet formed | Temporary magnet | Permanent magnet |
| How long magnetism lasts | Very short time | Many years / Long time |
Mark scheme: 1 mark for each correct answer (4 × 1 mark)
(b)
Soft iron is used because it magnetises easily when current flows through the coil and loses its magnetism quickly when the current stops. This allows the electromagnet to be switched on and off. Steel would stay magnetic even after the current was switched off, which would make the electromagnet useless.
Mark scheme: 1 mark for explaining soft iron magnetises and demagnetises easily, 1 mark for stating it needs to switch on/off or steel stays magnetic
4. A teacher demonstrates magnetic fields using a bar magnet and a compass.
(a) Define the term “magnetic field”. [2 marks]
(b) State the direction of a magnetic field at any point. [2 marks]
(c) Describe the steps the teacher should follow to plot magnetic field lines using a compass. [5 marks]
(a)
A magnetic field is a region (or space) around a magnet where a magnetic pole experiences a force.
Mark scheme: 1 mark for “region” or “space”, 1 mark for “magnetic pole experiences force”
(b)
The direction of a magnetic field at a point is the direction of the force that would act on a north pole placed at that point. / The direction a north pole would move at that point.
Mark scheme: 1 mark for mentioning north pole, 1 mark for direction of force/movement
(c)
1. Place the bar magnet on a sheet of paper and draw around it
2. Place a plotting compass near the north pole of the magnet
3. Mark the position of both ends of the compass needle with dots
4. Move the compass so that the south end is where the north end was before
5. Mark the new position of the north end of the compass needle
6. Repeat this process, moving the compass along until you reach the south pole
7. Join all the dots with a smooth curve and add an arrow showing direction from north to south
8. Repeat from different starting positions to plot several field lines
2. Place a plotting compass near the north pole of the magnet
3. Mark the position of both ends of the compass needle with dots
4. Move the compass so that the south end is where the north end was before
5. Mark the new position of the north end of the compass needle
6. Repeat this process, moving the compass along until you reach the south pole
7. Join all the dots with a smooth curve and add an arrow showing direction from north to south
8. Repeat from different starting positions to plot several field lines
Mark scheme: Award 5 marks for a clear description including:
• 1 mark for placing compass near north pole
• 1 mark for marking positions of compass
• 1 mark for moving compass systematically
• 1 mark for joining dots/drawing line
• 1 mark for adding arrows or repeating for multiple lines
• 1 mark for placing compass near north pole
• 1 mark for marking positions of compass
• 1 mark for moving compass systematically
• 1 mark for joining dots/drawing line
• 1 mark for adding arrows or repeating for multiple lines
5. A bar magnet has magnetic field lines around it.
(a) State the direction that magnetic field lines go outside a bar magnet. [1 mark]
(b) Explain why the magnetic field lines are closer together near the poles of the magnet. [2 marks]
(c) A student places a small plotting compass at a point near the north pole of the magnet. State which direction the north pole of the compass needle will point. [1 mark]
(d) Explain your answer to part (c). [2 marks]
(a)
From north pole to south pole / From N to S
Mark scheme: 1 mark for correct direction
(b)
The spacing of field lines indicates the strength of the magnetic field. The field lines are closer together near the poles because the magnetic field is strongest at the poles. The closer the lines, the stronger the field.
Mark scheme: 1 mark for stating field is strongest at poles, 1 mark for linking closer lines to stronger field
(c)
Away from the north pole / Toward the south pole of the magnet
Mark scheme: 1 mark for correct direction
(d)
The north pole of the compass needle points in the direction of the magnetic field. Since like poles repel, the north pole of the compass is pushed away from the north pole of the magnet (and pulled toward the south pole).
Mark scheme: 1 mark for explaining compass points in field direction, 1 mark for explaining repulsion between like poles
6. A student wants to show the magnetic field pattern around a bar magnet using iron filings.
(a) Describe the procedure the student should follow. [4 marks]
(b) Explain why the iron filings arrange themselves in a pattern around the magnet. [3 marks]
(c) State one advantage of using iron filings instead of a compass to show the magnetic field pattern. [1 mark]
(a)
1. Place a bar magnet on a flat surface
2. Place a sheet of paper or thin plastic over the magnet
3. Sprinkle iron filings evenly over the paper
4. Gently tap the paper to help the filings move and settle
5. The filings will arrange themselves showing the magnetic field pattern
2. Place a sheet of paper or thin plastic over the magnet
3. Sprinkle iron filings evenly over the paper
4. Gently tap the paper to help the filings move and settle
5. The filings will arrange themselves showing the magnetic field pattern
Mark scheme: Award up to 4 marks for clear steps including:
• 1 mark for placing magnet under paper/card
• 1 mark for sprinkling iron filings
• 1 mark for tapping paper
• 1 mark for observing pattern
(b)
• 1 mark for placing magnet under paper/card
• 1 mark for sprinkling iron filings
• 1 mark for tapping paper
• 1 mark for observing pattern
Each iron filing becomes magnetised through induced magnetism when placed in the magnetic field. The filings act like tiny compass needles. The north pole of one filing attracts the south pole of the next filing, causing them to line up in chains along the magnetic field lines, making the field pattern visible.
Mark scheme: 1 mark for induced magnetism, 1 mark for filings becoming magnets, 1 mark for explaining they line up along field lines
(c)
Iron filings show the complete field pattern quickly and all at once / Shows the overall shape of the field / Faster than plotting with a compass
(Accept any reasonable advantage)
(Accept any reasonable advantage)
Mark scheme: 1 mark for any valid advantage
7. A magnet is used to pick up a chain of steel paper clips. Each paper clip touches the one below it, forming a vertical chain.
(a) Explain why the paper clips form a chain rather than falling off. [3 marks]
(b) Predict what will happen when the magnet is removed from the top paper clip. [1 mark]
(c) Explain your answer to part (b). [2 marks]
(a)
The first paper clip becomes magnetised through induced magnetism when it touches the permanent magnet. This magnetised paper clip then induces magnetism in the second paper clip, making it magnetic. Each paper clip magnetises the one below it. The paper clips attract each other because opposite poles face each other, forming a chain.
Mark scheme: 1 mark for induced magnetism, 1 mark for each clip magnetising the next, 1 mark for explaining attraction holds chain together
(b)
The chain will fall apart / The paper clips will fall
Mark scheme: 1 mark for predicting chain falls apart
(c)
When the permanent magnet is removed, the paper clips lose their induced magnetism because steel loses its temporary magnetism quickly. Without magnetism, there is no magnetic attraction to hold the chain together, so the paper clips fall.
Mark scheme: 1 mark for explaining loss of magnetism, 1 mark for explaining no force to hold chain
Note: Some steel paper clips may retain a tiny amount of magnetism, but not enough to hold a chain.
8. Give two uses for each type of magnet:
(a) Permanent magnets [2 marks]
(b) Electromagnets [2 marks]
(c) Explain why electromagnets are more useful than permanent magnets for scrapyard cranes that lift and move metal. [2 marks]
(a) Permanent magnets:
1. Compasses for navigation
2. Fridge magnets
Also accept: loudspeakers, magnetic door catches, toys, computer hard drives, credit card strips
2. Fridge magnets
Also accept: loudspeakers, magnetic door catches, toys, computer hard drives, credit card strips
Mark scheme: 1 mark for each valid use (2 × 1 mark)
(b) Electromagnets:
1. Scrapyard cranes for lifting metal
2. Electric bells
Also accept: circuit breakers, relays, electric motors, MRI scanners, maglev trains, sorting machines
2. Electric bells
Also accept: circuit breakers, relays, electric motors, MRI scanners, maglev trains, sorting machines
Mark scheme: 1 mark for each valid use (2 × 1 mark)
(c)
Electromagnets can be switched on and off by controlling the electric current. This allows the crane to pick up metal when the current is on, move it to a new location, then release it by switching the current off. A permanent magnet would hold the metal continuously and could not release it easily.
Mark scheme: 1 mark for explaining can switch on/off, 1 mark for explaining advantage for picking up and releasing metal
9. A student investigates how distance affects the strength of a magnetic field. She places a bar magnet on a table and uses a compass at different distances from the north pole.
(a) Predict what the student will observe as she moves the compass further away from the magnet. [2 marks]
(b) Describe how the spacing of magnetic field lines changes with distance from the magnet. [2 marks]
(c) Explain what the spacing of magnetic field lines tells us about the strength of the magnetic field. [2 marks]
(a)
The compass needle will deflect less strongly as it moves further from the magnet. Very close to the magnet, the needle points directly away from the north pole, but further away, the deflection becomes smaller until eventually the compass just points north (Earth’s magnetic field) when too far from the magnet.
Mark scheme: 1 mark for stating less deflection with distance, 1 mark for explaining effect becomes weaker
(b)
The magnetic field lines are very close together near the poles of the magnet. As you move further away from the magnet, the field lines spread out and become further apart.
Mark scheme: 1 mark for close together near poles, 1 mark for spread out further away
(c)
The spacing of magnetic field lines represents the relative strength of the magnetic field. Where lines are close together, the field is strong. Where lines are spread out, the field is weak. This shows that the magnetic field gets weaker with distance from the magnet.
Mark scheme: 1 mark for linking close lines to strong field, 1 mark for linking spread lines to weak field
10. Two students are discussing magnetic forces.
Student A says: “Magnets need to touch each other to exert forces.”
Student B says: “Magnetic forces are caused by interactions between magnetic fields.”
(a) State which student is correct. [1 mark]
(b) Explain why magnetic forces can act without the magnets touching each other. [3 marks]
(c) Give one piece of evidence from everyday life that shows magnetic forces can act at a distance. [1 mark]
(a)
Student B is correct
Mark scheme: 1 mark for Student B
(b)
Each magnet creates a magnetic field in the space around it. When two magnets are brought close together, their magnetic fields overlap and interact with each other. This interaction between the fields creates forces of attraction or repulsion. The magnetic field extends through space, so the magnets can exert forces on each other without touching, as long as they are close enough for their fields to interact.
Mark scheme: 1 mark for mentioning magnetic fields, 1 mark for explaining fields interact, 1 mark for stating force acts through space/at distance
Important: This is a Supplement topic – understanding that magnetic forces are due to field interactions.
(c)
A magnet can pick up paper clips without touching them / Fridge magnets stick to the fridge through air / Two magnets repel each other before they touch / A compass needle moves when a magnet approaches it
(Accept any reasonable everyday example)
(Accept any reasonable everyday example)
Mark scheme: 1 mark for any valid example
Final Revision Tips for Magnetism:
- Pole Rules: Like poles repel, unlike poles attract – applies to magnets only
- Magnetic Materials: Iron, Nickel, Cobalt, Steel – these are ALWAYS attracted to magnets
- Soft Iron vs Steel: Soft iron = temporary (easy in, easy out), Steel = permanent (hard in, hard out)
- Field Lines: Always go N→S outside the magnet, closer lines = stronger field
- Field Direction: Direction a north pole would move at that point
- Induced Magnetism: Unmagnetised magnetic materials become temporary magnets near permanent magnets
- Breaking Magnets: Each piece becomes a complete magnet with N and S poles
- Plotting Methods: Compass shows direction, iron filings show pattern
- Uses: Permanent magnets for constant field (compass), electromagnets for switching on/off (cranes, bells)
- Supplement: Magnetic forces due to field interactions, field strength shown by line spacing
Common Exam Mistakes to Avoid:
- ❌ Don’t say magnets repel iron/steel – they always attract magnetic materials
- ❌ Don’t confuse magnetic materials (iron, nickel, cobalt, steel) with non-magnetic metals (aluminum, copper)
- ❌ Don’t forget that breaking a magnet gives two complete magnets, not separate poles
- ❌ Don’t say steel is used in electromagnets – soft iron is correct
- ❌ Don’t draw field lines crossing each other – they never cross
- ❌ Don’t forget arrows on field lines – they show direction (N→S)
