Question

In which of the following zones of atmosphere is the ozone layer present?
A. Ionosphere
B. Mesosphere
C. Stratosphere
D. Troposphere

Answer 1

Hint: Based on the temperature, earth’s atmosphere is divided into five zones, they are tropho, strato, meso, thermo and exospheres , where the important ozone layer is present in the stratosphere.

Complete answer:
> Troposphere: it is the lowest part of the atmosphere, it almost contains all clouds etc, where the temperature of the earth decreases by 6.5 degree per kilometre.
Troposphere contains almost all the 75% of the air on the earth and all the water vapour. Where the lowest part of the troposphere contains all the wind and this wind form the turbulence and it is useful to produce electricity from wind energy.

> Stratosphere: It starts from the troposphere to 50km away, where the majority of the ozone layer is present.
The temperature in the ozone layer is highest in the summer and lowest in the winter.
But the temperature increases due to absorption of uv radiation from the sun, because of maximum absorption of uv rays by ozone layer it protects us from skin cancers and other health damages.
But because of the pollution on the atmosphere, we are causing so much damage in ozone layer, controlling the pollution heals the damage in future.

> Mesosphere: The region above the stratosphere is the region again where the temperature decrease with increase in height.

> Thermosphere and ionosphere: Thermosphere usually lies above the mesosphere. The ionosphere is the layer which is 80kms away and it is the layer where all the broadcast and all is done. This layer has a lot of free ions and electrons, which are able to reflect the radio waves, usually extending from 80 to 1000 kilometres away from the earth, where ionization is due to solar radiation, it is the layer which is very important and helpful for radio propagation throughout the earth.

Correct Answer is C. Stratosphere.

Additional information: Exosphere: it is the layer which is 500 kms away and it contains all oxygen and hydrogen ions.

Note: Almost 90% of the ozone layer on the earth is found in the stratosphere, where it is usually 18 to 48 kms away from the earth, in this layer the ozone is more concentrated and protects us from several health hazards by absorbing the power full of UV rays.