A student fixes a sheet of white paper on a drawing board using some adhesive materials. She places a bar magnet in the centre of it and sprinkles some iron filings uniformly around the bar magnet using a salt-sprinkler. On tapping the board gently, she observes that the iron filings have arranged themselves in a particular pattern.
Generated by claude-sonnet-4-6 · 2026-06-15 06:49 · grounding stimulus
Model Answer
(a) Pattern of iron filings around a bar magnet:
```
N ←————→ S
(curved lines radiating outward from N,
looping around and entering at S)
```
The iron filings arrange in curved lines emerging from the North pole, arching outward, and converging at the South pole.
---
(b) Magnetic field lines of a bar magnet:
```
← ← ←
↗ curves outward ↘
N ——————————————— S
↖ curves outward ↙
← ← ←
```
- Field lines emerge from North (N) pole and enter the South (S) pole outside the magnet.
- Inside the magnet, field lines run from S to N.
- Lines are closer near the poles (stronger field) and spread out farther away.
---
(c) (Note: The alternatives for part (c) were not printed in the passage. Based on standard CBSE Class 10 Chapter 13 — Magnetic Effects of Electric Current, a likely question and answer is:)
What does the pattern of iron filings represent, and what are two properties of magnetic field lines?
The pattern of iron filings represents magnetic field lines of the bar magnet.
Two properties:
- Magnetic field lines are closed continuous curves — they emerge from the North pole, go around, and re-enter at the South pole, continuing inside the magnet from S to N.
- No two magnetic field lines intersect each other, because if they did, it would mean two directions of the magnetic field at that point, which is impossible.
Source: Chapter 13 – Magnetic Effects of Electric Current, NCERT Class 10 Science
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Explanation
- (a): Draw or describe curved lines around the magnet — denser near poles, sparser at sides. Examiners accept a neat labelled sketch.
- (b): Key requirement: label N and S poles clearly and show arrows on field lines (N → outside → S). Direction is mandatory for full marks.
- (c): Since the alternatives were missing from the passage, the answer above covers the most commonly asked 2-mark MCQ/short-answer on this topic. Always state two distinct properties with brief explanation for 2-mark property-based questions.
- Remember: field lines never cross, they are closed loops, and density of lines indicates field strength.