Why do iron filings show magnetic field patterns?

Question

Iron is ferromagnetic, and so its magnetic domain strongly aligns with the magnetic field. Because iron filings are small, they are light enough that the torque created by the magnetic field aligns the whole filing in the direction of the field. Enough filings display the pattern of the magnetic field.
Iron is ferromagnetic, and so its magnetic domain strongly aligns perpendicular to the magnetic field. Because iron filings are small, they are light enough that the torque created by the magnetic field aligns the whole filing perpendicular to its magnetic domain, pointing the filing in the direction of the magnetic field. Enough filings display the pattern of the magnetic field.
Iron filings are rough, so they rub together to create static electricity. The free charges moving from filing to filing create an electromagnet, which is strong enough to turn the filings in the direction of the magnetic field. Enough filings create a large enough electromagnet to display the entire magnetic field pattern.

Answer 1

Iron filings show magnetic field patterns because they align themselves along the magnetic field lines due to their ferromagnetic properties. When placed near a magnet, the iron filings are attracted to the magnetic field lines and align themselves in the direction of the field. This alignment allows the iron filings to form patterns that represent the shape and strength of the magnetic field around the magnet. By studying these patterns, scientists can visualize and understand the magnetic field in a particular area.