A. Automobile exhaust
B. Forest fire
C. Bacterial action in soil and swamp areas
D. All A., B. and C.
Related Mcqs:
- Which of the following is not a natural source of air pollution ?
A. Volcanic eruptions and lightening discharges
B. Biological decay of vegetable matter
C. Photochemical oxidation of organic matter
D. None of these - Which of the following acts as a natural source of air pollution ?
A. Forest fire
B. Deforestation
C. Volcanic eruption
D. None of these - ‘Safe limit’ called Threshold Limit Value (TLV) of carbon monoxide in atmospheric air is < 50 ppm. The main source of carbon monoxide pollutant in air is the____________________?
A. Industrial chimney exhaust
B. Automobiles exhaust
C. Photochemical reaction in polluted atmosphere
D. Burning of domestic fuel - Which of the following sources is responsible for maximum air pollution ?
A. Industrial chimney exhaust
B. Forest fire
C. Automobiles exhaust
D. Photochemical oxidation of organic matter - From pollution control point of view, the maximum permissible concentration of sulphur dioxide in atmospheric air is about ________________ ppm?
A. 5
B. 50
C. 500
D. 5000 - Atmospheric pollution caused by the exhaust gas of supersonic transport air-crafts is mostly in the atmospheric region called________________?
A. Thermosphere
B. Stratosphere
C. Troposphere
D. Mesosphere - The main industrial source of emission of hydrogen sulphide air pollutant is________________?
A. Petroleum refineries
B. Coal based thermal power plants
C. Pulp and paper plant
D. Metallurgical roasting & smelting plant - Noise produced by cooling fans (employed in air cooled heat exchangers or cooling tower) is mainly caused due to the turbulence created by blade passage through air. It can be reduced by use of a slower fan_________________?
A. With greater number of blades
B. Of increased diameter
C. Both A. & B.
D. Neither A. nor B. - Presence of nitrogen in high concentration in contaminated air reduces partial pressure of oxygen in lungs, thereby causing asphyxia (suffocation) leading to death from oxygen deficiency. Concentration of N2 in contaminated air at which it acts as a natural asphyxiate is ≥ _____________ percent?
A. 84
B. 88
C. 80
D. 92 - The density of the gases (present in air) decreases with increasing altitude to such an extent, that about 70% of the mass of atmospheric air is found in the lower 5 km. of the atmosphere. This lower region of atmosphere is called the_________________?
A. Ionosphere
B. Troposphere
C. Stratosphere
D. None of these
