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Usage of ultra-violet in sunbeds, fluorescent tubes and sterilization
- UV radiation is energetic enough to ionize atoms and so can cause harm to living tissue. Under excessive exposure, it will cause sunburn and skin cancers.
- It is used benefically in the sterilization of water, by killing off harmful living organisms present in the water for potable uses.
- Paper money are coated with invisible chemicals that only become reflective(visible) when UV radiation is incident on the paper. The main aim is to distinguish the real money from its counterfeits easily.
- Florescent tubes contain mercury vapour and their inner surfaces are coated with florescent poweders. Fluorescent materials absorb “invisible” ultraviolet radiation emitted by excited mercury atoms and re-radiate as “visible” light.
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