The lowest temperature is observed/recorded in which one of the following layers of the atmosphere?
- A.Stratosphere
- B.Mesosphere
- C.Thermosphere
- D.Troposphere
Correct answer
Explanation
The correct answer is B, Mesosphere. Temperature falls with height through the mesosphere and reaches the coldest values in the whole atmosphere, about minus 90 to minus 100 degrees Celsius, at its top.
The mesosphere lies above the stratosphere, from about 50 km up to about 80-85 km. With little ozone to absorb sunlight and very thin air, it keeps cooling with height until the mesopause. This is the layer where most meteors burn up as shooting stars, and the rare noctilucent clouds form near its upper edge.
A is wrong: in the stratosphere the ozone layer absorbs ultraviolet rays, so temperature rises with height.
C is wrong: the thermosphere absorbs high-energy solar radiation and its temperature climbs to well over 1,000 degrees Celsius.
D is wrong: the troposphere cools by about 6.5 degrees Celsius per kilometre, but its top is still warmer than the mesopause.
Exam tip: temperature falls in the troposphere, rises in the stratosphere, falls in the mesosphere (coldest), rises in the thermosphere.
Practice Questions
View allWhich one of the following rivers is west-flowing?
- A.Godavari
- B.Periyar
- C.Tungabhadra
- D.Cauvery
Show answer
The Periyar rises in the Western Ghats of Kerala and flows west into the Arabian Sea. The Periyar is the longest river of Kerala.
Read the full explanation →Which one of the following is not an igneous rock?
- A.Granite
- B.Gneiss
- C.Pumice
- D.Basalt
Show answer
Gneiss is a metamorphic rock, formed when existing rocks are changed by great heat and pressure. Igneous rocks form when molten magma or lava cools and hardens.
Read the full explanation →Consider the following places of India :
1. Itanagar
2. Imphal
3. Agartala
4. Aizawl
Which one of the following is the correct chronological order of the above places in terms of sunrise time?
- A.3-2-1-4
- B.2-1-4-3
- C.1-4-3-2
- D.4-3-2-1
Show answer
The sun rises first in the place farthest east, so the order follows longitude: Imphal, Itanagar, Aizawl and then Agartala.
Read the full explanation →"Viticulture" is a common feature of which one of the following Australian cities ?
- A.Adelaide
- B.Darwin
- C.Hobart
- D.Brisbane
Show answer
Viticulture, the growing of grapes, is a hallmark of Adelaide, which is surrounded by Australia's best-known wine regions. Adelaide, the capital of South Australia, has a Mediterranean climate with hot, dry summers and mild, wet winters, the conditions grapevines like best.
Read the full explanation →Which of the following statements regarding Barchan is/are correct ?
1. It is a crescent shaped mound of sand, which is deposited by the wind blowing constantly from one direction in a desert.
2. The windward side has a convex steep slope with maximum height at the centre.
3. Two ends of Barchan are called horns and point opposite to the direction the wind blows.
Select the answer using the code given below :
- A.1 only
- B.1 and 2 only
- C.2 and 3 only
- D.1, 2 and 3
Show answer
A barchan is a crescent-shaped sand dune built by wind from one steady direction, but its windward slope is gentle and its horns point downwind.
Read the full explanation →