Question
Write a short note on Ultra violet rays.
✓
Answer
→Wave length range: from 4 x 10-7 m (400 nm) to 6 x 10-10 m (0.6 nm)
→U.V. (or UV) radiation is produced by special lamps and very hot bodies.
→UV light in large quantities has harmful effects on humans.
→Exposure to UV radiation induces the production of more melanin, causing tanning of the skin, which is known as Sunburn.
→The Ozone layer in the atmosphere at an altitude of about 40-50 km absorbs the UV rays coming from the sun. In this way, it acts as a protecting shield for humans. Depletion of Ozone layer by chlorofluoro carbons (CFCs) gas (such as freon) is a matter of concern.
→Welders wear special glass goggles or face masks with glass windows to protect their eyes from large amount of UV produced by welding arcs. (Because UV radiation is absorbed by ordinary glass.)
→UV radiations can be focused into very narrow beams for high precision applications such as LASIK (Laser assisted in situ keratomileusis.) eye surgery.
→UV lamps are used to kill germs in water purifiers.
→U.V. (or UV) radiation is produced by special lamps and very hot bodies.
→UV light in large quantities has harmful effects on humans.
→Exposure to UV radiation induces the production of more melanin, causing tanning of the skin, which is known as Sunburn.
→The Ozone layer in the atmosphere at an altitude of about 40-50 km absorbs the UV rays coming from the sun. In this way, it acts as a protecting shield for humans. Depletion of Ozone layer by chlorofluoro carbons (CFCs) gas (such as freon) is a matter of concern.
→Welders wear special glass goggles or face masks with glass windows to protect their eyes from large amount of UV produced by welding arcs. (Because UV radiation is absorbed by ordinary glass.)
→UV radiations can be focused into very narrow beams for high precision applications such as LASIK (Laser assisted in situ keratomileusis.) eye surgery.
→UV lamps are used to kill germs in water purifiers.
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