Physics
Give reason for the following:
Ultraviolet bulbs have a quartz envelope instead of glass.
Related Questions
Give reason for the following:
A rock salt prism is used instead of a glass prism to obtain the infrared spectrum.
Give reason for the following:
A quartz prism is required for obtaining the spectrum of the ultraviolet light.
Radiations from the sun fall on a prism and suffer dispersion. Three thermometers are kept on which the radiations after dispersion are made to fall as shown in the figure given below. Which thermometer would show a higher reading ? Give a reason for your answer.

What are infrared radiations? How are they detected? State one use of these radiations.