MCQ
Pick out the electromagnetic wave which is highly harmful to humans.
- ARadio waves
- ✓Ultraviolet Rays
- CMicrowaves
- DInfrared Waves
✓
Answer
Correct option: B.
Ultraviolet Rays
Ultraviolet $(UV)$ radiations in large quantities are highly harmful to humans. These rays in solar radiation on reaching earth are absorbed by the ozone layer in the atmosphere. $UV$ rays are produced by special lamps such as mercury and from arc lamps and by very hot bodies like the sun.
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