Free Environment and Atmosphere MCQs with Answers

101. Earthquakes are caused by:

• A. Landslide
• B. Eruption of volcanoes
• C. Tectonic plates
• D. All of these

Explanation: Most earthquakes result from sudden movement of tectonic plates, but volcanic eruptions and landslides can also produce earthquakes. Thus all the listed processes can be causes.

102. Mouna Loa is an example of?

• A. Active volcano
• B. Extinct volcano
• C. Plateau in volcanic region
• D. None of these

Explanation: Mauna Loa in Hawaii is an active shield volcano that has erupted repeatedly in historical times. It is not extinct or merely a plateau.

103. Atmospheric pressure at sea level is _______?

• A. 746 mm
• B. 760 mm
• C. 820 mm
• D. None of these

Explanation: Standard atmospheric pressure at mean sea level is 760 mm of mercury, equivalent to one atmosphere or about 101.3 kilopascals. The value changes with altitude and weather, but 760 mm is the standard reference.

104. Ozone layer thickness is measured in____________?

• A. Metre
• B. Joule
• C. Pounds
• D. Dobson

Explanation: The amount of ozone in the atmosphere is measured in Dobson units, with one Dobson unit representing a very thin layer of pure ozone under standard conditions. Metre measures length, not atmospheric ozone concentration.

105. Which of the following is cold current ?

• A. Gulf Stream
• B. Brazil
• C. Benguela
• D. Kuroshio

Explanation: The Benguela Current is a cold current flowing northward along the southwest coast of Africa. The Gulf Stream, Brazil, and Kuroshio currents are warm currents.

106. The term 'Geography' was coined first time by a Greek scholar _________ in 234BC?

• A. Herodotus
• B. Thales of Miletus
• C. Eratosthenes
• D. Plato

Explanation: Eratosthenes, a Greek scholar and mathematician, is generally credited with coining the term geography. He also made an early calculation of Earth’s circumference.

107. There are ______ themes in geography.

• A. Three
• B. Four
• C. Five
• D. Seven

Explanation: The commonly taught five themes of geography are location, place, human-environment interaction, movement, and region. These themes provide a framework for organizing geographical study.

108. The earth surface & crust constantly evolving due to ?

• A. Rotary cycle
• B. Normal cycle
• C. Rock cycle
• D. Change cycle

Explanation: The rock cycle describes the continuous formation, breakdown, and transformation of rocks through processes such as melting, cooling, weathering, and pressure. It helps explain why Earth’s crust is constantly changing.

109. Which type of climates of world has dry summer & wet winter ?

• A. Western European type
• B. Mediterranean type
• C. Equatorial type
• D. Tundra type

Explanation: The Mediterranean climate has hot, dry summers and mild, wet winters, largely because seasonal wind belts shift over the region. The other listed climate types do not have this characteristic pattern.

110. Sedimentary rocks are formed by natural process known as ?

• A. Lithification
• B. Rejuvenation
• C. Hydration
• D. Peroxidation

Explanation: Lithification is the process by which deposited sediments become solid rock through compaction and cementation. The other terms do not describe sedimentary-rock formation.