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When an unmagnetized piece of iron is heated, the dipoles are disaligned. Both ends of the hot iron piece are placed facing the North and South poles of the magnetized field. The North poles of the dipoles and South poles of the dipoles are attracted to the South pole and North pole of the magnetized field respectively. On cooling, the piece of iron becomes magnetized possessing distinct North and South poles.
Andreaz answered the question on November 22, 2017 at 08:02
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