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प्रश्न
Boojho made an electromagnet by winding 50 turns of wire over an iron screw. Paheli also made an electromagnet by winding 100 turns over a similar iron screw. Which electromagnet will attract more pins? Give reason.
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उत्तर
Paheli’s electromagnet will attract more pins as it has more number of turns of wire on it and thus a stronger electromagnet.
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