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प्रश्न
How is scrap iron separated from a heap of waste materials in factories?
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उत्तर
Scrap iron is separated from a heap of waste materials in factories by using large electromagnets fitted to a crane. The electromagnet fitted crane is moved up and away from the waste to drop these scrap iron objects at a separate place. Electromagnets are used for this purpose because one can switch on and off the supply of magnetism during the process of lifting and dropping of the iron pieces.
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