Section 1: Prior Knowledge
1. Where have you seen or used a magnet in your daily life?
Answer:
· Refrigerator door
· School bag magnetic clasp
· Magnetic toys
· Loudspeakers
· Compass
· Door catches
2. What do you think a magnet can do?
Answer:
A magnet attracts magnetic materials such as iron, nickel, and cobalt. It can also attract or repel another magnet and can help us find directions using a magnetic compass.
3. Anything you know about magnetic fields you would like to share?
Answer:
A magnetic field is the invisible region around a magnet where its magnetic force can be felt. The field is strongest near the poles.
Section 2: Activity Log
1. Aim
Answer:
To observe and compare the magnetic field patterns around different types of magnets using iron filings.
2. Materials
Answer:
· Bar magnet
· Ring magnet
· Iron filings
· Butter paper
· Foam sheet
· Tapper/finger for gentle tapping
3. Hypothesis
✔ Iron filings gather more near the poles of a magnet.
✔ Different magnets produce different magnetic field patterns.
❌ Iron filings spread evenly around a magnet. (Incorrect)
Other hypothesis:
The magnetic field becomes weaker as the distance from the magnet increases.
5. Observation Table – Showing a Magnetic Field Pattern
Type of Magnet | Where do the iron filings gather the most? | Where do the iron filings gather the least? | ||
| Prediction | Actual Result | Prediction | Actual Result |
Bar Magnet | Near the two poles (ends) of the magnet | Iron filings gathered densely near both poles, showing the magnetic field is strongest there. | Near the centre of the magnet | Very few iron filings gathered at the centre because the magnetic field is weaker there. |
Ring Magnet | Around the magnetic poles (on the flat circular faces/edges, depending on the magnet) | Iron filings gathered densely around the poles of the ring magnet, forming a circular magnetic field pattern. | At the middle region away from the poles | Fewer iron filings were seen in the middle region because the magnetic field is weaker there. |
Section 3: Analyse, Apply and Reflect
1. What pattern did you notice around the bar magnet? Why?
Answer:
The iron filings formed curved lines joining one pole to the other. They were crowded near the poles because the magnetic field is strongest there.
2. Two paper clips are placed near a bar magnet.
Answer:
The paper clip near the end (pole) of the magnet will be attracted more because the magnetic force is strongest at the poles.
3. What did you learn today?
Answer:
· Magnets produce invisible magnetic fields.
· Iron filings help us see magnetic field patterns.
· Magnetic field is strongest at the poles.
· Different magnets have different field patterns.
Section 4: Competency-Based Assessment
1. When iron filings were sprinkled around a magnet, what did they form?
✅ Answer:
A pattern around the magnet.
2. Where were the iron filings most closely packed?
✅ Answer:
Near the poles of the magnet.
3. A compass is placed very close to a bar magnet.
✅ Answer:
No, because the nearby magnet affects the compass needle.
4. Assertion–Reason
Assertion (A): More iron filings are attracted to the centre of the magnet.
Reason (R): The centre of the magnet is stronger than the poles.
✅ Answer:
Both A and R are false.
Explanation:
Iron filings gather near the poles, not at the centre.
5. Arrange the points according to magnetic field strength.
Answer:
A = B > C > D
(or)
A, B, C, D
6. Alternative to butter paper
Answer:
Alternative: Plastic sheet or transparent OHP sheet.
Property: It is thin, smooth, non-magnetic, and allows the magnetic field to pass through while preventing iron filings from sticking directly to the magnet.
7. "The bigger the magnet, the stronger it is."
Answer:
Disagree.
The strength of a magnet depends on its material and magnetization, not only on its size. A small magnet can sometimes be stronger than a larger one.
8. What is a magnetic field? Write two properties.
Answer:
A magnetic field is the region around a magnet where magnetic force acts.
Properties:
1. It is strongest near the poles.
2. It becomes weaker as the distance from the magnet increases.
9. Possible sources of error
Answer:
Possible errors:
· Too many iron filings were used.
· The paper was shaken instead of tapped gently.
· The magnet moved during the activity.
· Wind disturbed the filings.
· Uneven surface.
Correcting these errors produces a clearer magnetic field pattern.
10. Iron filings are not available. Suggest another method.
Answer:
A magnetic compass can be used.
Move the compass around the magnet and mark the direction in which the needle points at different places. Joining these directions forms the magnetic field pattern around the magnet.
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