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Question
Answer the following in detail.
List four methods of magnetizing a magnetic substance.
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Solution
Methods of magnetizing a magnetic material are :
- Single-touch method – A magnet is rubbed along the magnetic substance from one end to another.
- Double-touch method – Opposite poles of two magnets are placed next to each other at the centre of the magnetic substance and rubbed in opposite direction along it.
- Magnetizing by induction – It is a method to make temporary magnets under the influence of a magnetizing force. The magnetic properties disappear when the influence of the magnetizing force is removed.
(A permanent magnet is brought close to the magnetic substance but not touched.) - Electric current – A magnet made by using electric current is called an electromagnet. It is a temporary magnet and stops behaving like a magnet when the current is stopped. Electromagnets can become permanent magnets if certain materials like steel and special alloys are placed in a coil and a very strong current is passed through the coil.
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