May 13, 2022, 16:45 IST
The word ‘resource’ is used for means of supplying a material generally held in reserve .
Component | Volume |
Nitrogen (N 2 ) | 78.08 % |
Oxygen (O 2 ) | 20.92 % |
Carbon dioxide (CO 2 ) | 0.03 % |
Argon | 0.93 % |
Trace components* | 0.4 % |
Lower part of troposphere is the reservoir of gases that are essential for life, e.g., oxygen and carbon dioxide. Stratosphere has protective ozone shield (ozonosphere) that protects us from harmful UV radiations.
Air pollution is defined as an undesirable change in the physical, chemical or biological characteristics of air making it harmful for organisms (including man). The agents or substances that pollute the air are called air pollutants . There are two main sources of air pollution
Air pollution causes numerous harmful effects. These include:
NCERT solutions for class 9 Science is prepared by Physics Wallah and consist of solution of all questions asked in NCERT text book.
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