The correct option is (c).
Explanation
A magnet creates a magnetic field in the space surrounding it. The strength of this field is non-uniform and varies depending on the position relative to the magnet. Iron filings, being ferromagnetic, align themselves along magnetic field lines, providing a visual representation of the field's strength and direction.- Statement 1 is Correct: The magnetic field lines are most crowded near the ends of the magnet, known as the poles (North and South). Consequently, the magnetic force is strongest at the poles, resulting in the maximum accumulation and attraction of iron filings in these regions.
- Statement 2 is Incorrect: The magnetic force is not strongest at the center; rather, it is weakest in the central region of a bar magnet. The magnetic field lines spread out as they move away from the poles, and the external attractive force is minimal at the geometric center.
- Statement 3 is Correct: The pattern formed by iron filings maps the magnetic field lines. The density or concentration of filings at any specific point is directly proportional to the strength of the magnetic field at that point. Crowded filings indicate a strong field, while sparse filings indicate a weak field.
Key Takeaway: The magnetic strength of a bar magnet is concentrated at its poles and is weakest at its center. The density of magnetic field lines serves as a direct indicator of magnetic field strength.