Question

Answer the following questions :

(a) Optical and radio telescopes are built on the ground while X-ray astronomy is possible only from satellites orbiting the Earth. Why?

(b) The small ozone layer on top of the stratosphere is crucial for human survival. Why?

Answer 1

(a) The visible radiations and radiowaves can penetrate the earth'* atmosphere but X-rays are absorbed by the atmosphere.

(b) The ozone layer absorbs ultraviolet and other low wavelength radiations which are harmful to living cells of human bodies and plants; hence ozone layer is crucial for human survival.