What are ultraviolet radiations ? How are they detected ? State one use of these radiations.
The electromagnetic radiations of wavelength from 100Å to 4000Å 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 to the violet end, the solution remains unaffected. However, just beyond the violet end, it first turns violet and finally, it becomes dark brown. Thus there exist certain radiations beyond the violet end of the spectrum, which are chemically more active than visible light, called ultraviolet radiations.
Use: Ultraviolet radiations are used for sterilizing purposes.