A permanent magnet has a constant magnetic field and does not require electricity. An electromagnet, however, needs an electric current to generate its magnetic field, and its strength can be controlled.
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The strength of an electromagnet can be increased by increasing the electric current, adding more turns to the wire coil, or using a core with better magnetic properties, like soft iron.
A temporary magnet can be made by stroking a magnetic material, like iron, with a permanent magnet in one direction. This aligns the material’s magnetic domains temporarily, giving it magnetic properties.
Temporary magnets lose their magnetism quickly once the external magnetic field is removed, like soft iron. Permanent magnets, like bar magnets, retain their magnetism over time without needing an external field.
When you cut a magnet in half, each piece becomes a new magnet with its own north and south poles. This occurs because the magnetic domains realign, ensuring that both pieces have opposite poles.