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प्रश्न
Welders wear special goggles or face masks with glass windows to protect their eyes from electromagnetic radiations. Name the radiations and write the range of their frequency.
उत्तर
Welders wear special goggles with glass windows to protect the eyes from Ultra Violet rays (UV rays). The range of UV rays is 4×10-7 m (400 nm) to 6×10-10 m (0.6 nm).
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