Consider the following statements about temperature inversion: I. This happens when normal lapse rate gets inverted. II. Winter nights with cloudy skies are conducive for temperature inversion. III. Polar areas experience inversion throughout the year. Which of the statements given above are correct?
- A.I and II only
- B.II and III only
- C.I and III only
- D.I, II and III
Correct answer
Explanation
The correct answer is C, I and III only. Temperature inversion needs rapid cooling of the ground, which happens under clear skies, not cloudy ones. Statement I is correct: normally temperature falls with height, but during an inversion a layer of warmer air lies above cooler air near the ground, so the normal lapse rate is reversed. Statement II is wrong: the ideal conditions are long winter nights, clear skies, calm air and dry air. Clouds act like a blanket, trapping outgoing heat and keeping the ground warm, so cloudy nights work against inversion. Statement III is correct: in polar regions the ground stays very cold almost all year, so surface inversion is normal there throughout the year. Inversions also cause fog in valleys and trap smoke and pollution near the ground. Option A is wrong because it includes statement II. Option B is wrong because it includes statement II and drops statement I. Option D is wrong because statement II is false. Exam tip: inversion needs long nights, clear skies and still air.
Practice Questions
View allWhich of the following statements with reference to Glacial trough is/are correct ?
1. Alpine glaciers strip valleys of their soil, regolith and sediment to form glacial troughs.
2. When the sea level is below the floor of a glacial trough, the seawater enters as the ice front recedes, creating a fiord.
Select the answer using the code given below :
- A.1 only
- B.2 only
- C.Both 1 and 2
- D.Neither 1 nor 2
Show answer
Valley glaciers scour away soil, regolith and loose sediment and deepen their valleys into U-shaped glacial troughs, but a fiord forms only when the trough floor lies below sea level, not above it.
Read the full explanation →Which of the following statements with reference to Richter scale is/are correct ?
1. It is the intensity scale of an earthquake.
2. Richter indicates the amount of energy released during the earthquake.
Select the answer using the code given below :
- A.1 only
- B.2 only
- C.Both 1 and 2
- D.Neither 1 nor 2
Show answer
The Richter scale measures the magnitude of an earthquake, which reflects the energy released at its source, not its intensity.
Read the full explanation →Dry land farming in India is largely confined to areas with rainfall less than
- A.100 cm
- B.85 cm
- C.80 cm
- D.75 cm
Show answer
Dryland farming is practised where annual rainfall is below about 75 cm. Indian agriculture is grouped by the source of moisture into irrigated and rainfed farming, and rainfed farming is further divided into dryland and wetland farming.
Read the full explanation →Which of the following statements regarding humidity is/are correct?
1. It is a ratio between the actual amount of water vapour present in the atmosphere and the maximum amount it can hold at a given temperature.
2. When the relative humidity is high, more water evaporates from the skin.
3. Higher the air temperature lower the relative humidity of the air.
Select the answer using the code given below:
- A.1 only
- B.2 and 3 only
- C.1 and 3 only
- D.1, 2 and 3
Show answer
Relative humidity compares the moisture in the air with what the air could hold, and that capacity rises with temperature.
Read the full explanation →Which one among the following processes is NOT part of chemical weathering?
- A.Solution
- B.Hydration
- C.Reduction
- D.Thawing
Show answer
Thawing is the melting of ice, a physical change that works on rocks only mechanically.
Read the full explanation →