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Question
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.
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Solution
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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