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प्रश्न
Name two electromagnetic waves of frequency smaller than that of violet light. State one use of each.
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उत्तर
1) Ultraviolet radiations - 100 Å to 4000 Å
Use: For detecting purity of gems, eggs, ghee, etc.
2) X-rays - 0.1 Å to 100 Å
Use: For detecting fracture in bones, teeth, etc.
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