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Question
Describe the method by which an iron bar can be made a magnet.
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Solution
Single touch method: Place the iron bar (or the needle) AB on a table. Take a bar magnet NS and place it almost vertical with its north pole (N) on the end A of the bar.
Move the magnet along tire iron bar till the other end B is reached.
Lift the magnet at the end B and again place it on the first end 'A' as shown by the arrows in the diagram. Again, stroke the bar. Repeat the process about 20 times. Then turn the iron bar AB upside down. Again, stroke it with the magnet about 20 times. The bar now becomes a magnet.
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