Question

What are ultraviolet radiations? How are they detected? State two properties and one use of ultraviolet radiations.

Answer 1

The electromagnetic radiations of wavelength from 100 Å to 4000 Å are called the ultraviolet radiations.

Detection: If the different radiations from the red part of the spectrum to the violet end and beyond it are made incident on the silver-chloride solution, it is observed that from the red end to the violet, the solution remains almost unaffted. However just beyond the violet end, it first turns violet and finally it becomes dark brown (or black). thus, there exist certain radiations beyond the violet end of the spectrum, which are chemically more active than the visible light. Thses radiations are called the ultraviolet radiations.

Two properties of ultraviolet radiation:

1. Ultraviolet radiation can pass through quartz, but they are absorbed by glass.

2. They are usually scattered ny the dust particles present in the atmosphere.

one use of ultraviolet radiation:

in producing, Vitamin D, in food of plans and animals.