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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.
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उत्तर
Welders wear special goggles to protect their eyes from Ultraviolet (UV) rays and Infrared (IR) rays. The range of UV rays is 8 × 1014 Hz to 5 × 1017 Hz. The range of IR rays is 3 × 1011 Hz to 4 × 1014 Hz.
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