Consider the following statements related to water vapours: 1. It is a variable gas in the atmosphere, which decreases with altitude. 2. In the dry and cold areas of desert and polar regions, it may be less than one per cent of the air. Which of the statements given above is/are correct?
- A.1 only
- B.2 only
- C.Both 1 and 2
- D.Neither 1 nor 2
Correct answer
Explanation
The correct answer is C, Both 1 and 2. Water vapour is a variable gas whose share of the air changes from place to place and falls with height, and it is scarce in cold and dry regions.
Warm air can hold much more moisture than cold air, and most evaporation takes place near the surface. So water vapour is concentrated in the lower layers of the atmosphere and thins out with altitude. In the warm and wet tropics it may make up about four per cent of the air by volume, while over hot deserts and the cold polar regions it may be less than one per cent. Water vapour absorbs heat from the sun and from the earth, so it acts like a blanket.
A is wrong because statement 2 is also correct. B is wrong because statement 1 is also correct. D is wrong because both statements match the standard description of water vapour.
Exam tip: water vapour is up to 4 per cent in the humid tropics and below 1 per cent in deserts and polar areas.
Practice Questions
View allDoldrum are
1. equatorial calms
2. calm and light winds
3. roaring forties
4. variable both in position and in extent
Select the correct answer using the code given below:
- A.1, 2 and 4
- B.2 and 3 only
- C.1 and 3
- D.2, 3 and 4
Show answer
The doldrums are the equatorial belt of calm and light, variable winds, and the belt shifts with the seasons; they have nothing to do with the roaring forties.
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- B.Bhagalpur
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- A.shifting cultivation.
- B.mixed farming.
- C.truck farming.
- D.plantation agriculture.
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Read the full explanation →The Tetrahedral Hypothesis of the origin of continents and ocean basin was proposed by
- A.F.B. Taylor
- B.Lowthian Green
- C.Alfred Wegener
- D.W.M. Davis
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Read the full explanation →Which one of the following statements is correct?
For the purpose of Census 2011
- A.a person aged seven and above who can both read and write with understanding in any language is treated as a literate
- B.a person aged eight and above who can both read and write with understanding in any language is treated as a literate
- C.a person aged nine and above who can both read and write with understanding in any language is treated as a literate
- D.a person aged ten and above who can both read and write with understanding in any language is treated as a literate
Show answer
In Census 2011, a person aged seven and above who could both read and write with understanding in any language was counted as literate.
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