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प्रश्न
What are the ultraviolet rays?
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उत्तर
- Ultraviolet rays can be produced by the mercury-vapor lamp, electric spark, and carbon arc lamp.
- They can also be obtained by striking electrical discharge in hydrogen and xenon gas tubes.
- The Sun is the most important natural source of ultraviolet rays, most of which is absorbed by the ozone layer in the Earth’s atmosphere.
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