Read the statements given below.
(i) Value of the wind profile exponent for the 'very unstable' atmosphere is smaller than the wind profile exponent for the 'neutral' atmosphere.
(ii) Downwind concentration of air pollutants due to an elevated point source will be inversely proportional to the wind speed.
(iii) Value of the wind profile exponent for the 'neutral' atmosphere is smaller than the wind profile exponent for the 'very unstable' atmosphere.
(iv) Downwind concentration of air pollutants due to an elevated point source will be directly proportional to the wind speed.
Select the correct option.
(i) Value of the wind profile exponent for the 'very unstable' atmosphere is smaller than the wind profile exponent for the 'neutral' atmosphere.
(ii) Downwind concentration of air pollutants due to an elevated point source will be inversely proportional to the wind speed.
(iii) Value of the wind profile exponent for the 'neutral' atmosphere is smaller than the wind profile exponent for the 'very unstable' atmosphere.
(iv) Downwind concentration of air pollutants due to an elevated point source will be directly proportional to the wind speed.
Select the correct option.
Show Hint
- (i) is False and (iii) is True
- (i) is True and (iv) is True
- (ii) is False and (iii) is False
- (iii) is False and (iv) is False
The Correct Option is D
Solution and Explanation
- Statement (ii): Downwind concentration of pollutants is inversely proportional to the wind speed, which is incorrect. As wind speed increases, the concentration decreases, not increases.
- Statement (iii): The wind profile exponent for a neutral atmosphere is larger than for a very unstable atmosphere. So, this statement is false.
- Statement (iv): Downwind concentration is inversely proportional to the wind speed, not directly proportional.
Thus, the correct answer is (D). Final Answer: (D) (iii) is False and (iv) is False
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