World and Physical Geography

381. In terms of geological time scale, the quaternary period consists of t

In terms of geological time scale, the quaternary period consists of two epochs. They are :

[amp_mcq option1=”Pleistocene and Pliocene” option2=”Holocene and Pleistocene” option3=”Pleistocene and Miocene” option4=”Holocene and Eocene” correct=”option2″]

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The correct option is B.
The Quaternary period, the most recent geological period in the Cenozoic Era, is divided into two epochs: the Pleistocene and the Holocene.
The Pleistocene epoch is characterized by repeated glaciation events and the evolution of modern humans. The Holocene epoch is the current epoch, beginning after the last glacial period ended, approximately 11,700 years ago, and is characterized by the rise of human civilization.

382. Which of the following statements is/are correct ? 1. Hypocenter is

Which of the following statements is/are correct ?

  • 1. Hypocenter is the point on the surface of the Earth, nearest to the focus.
  • 2. Velocity of earthquake waves is higher in denser materials.
  • 3. P waves move faster and are the first to arrive at the surface of the Earth.

Select the correct answer using the code given below :

[amp_mcq option1=”1 and 2″ option2=”2 and 3″ option3=”1 and 3″ option4=”3 only” correct=”option2″]

This question was previously asked in
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The correct option is B.
Statement 1 is incorrect because the hypocenter is the point of origin of the earthquake *within* the Earth, while the epicenter is the point *on the surface* directly above the hypocenter. Statement 2 is generally correct as seismic wave velocity increases with the rigidity and density of the medium. Statement 3 is correct; P waves (primary or compressional waves) are faster than S waves (secondary or shear waves) and arrive first.
1. Hypocenter (or focus) is the point below the Earth’s surface where the earthquake originates. The epicenter is the point on the Earth’s surface directly above the hypocenter.
2. Seismic wave speeds depend on the elastic properties and density of the material. Wave speed is proportional to the square root of the ratio of an elastic modulus (like bulk modulus or shear modulus) to density. While density increases with depth, the elastic moduli generally increase faster, leading to an overall increase in wave speed with depth in the Earth’s mantle and core.
3. P waves are longitudinal waves that can travel through solids, liquids, and gases. S waves are transverse waves that can only travel through solids. Because P waves involve compression and expansion, they travel faster than S waves, which involve shearing motion.

383. Which one of the following is not an igneous rock ?

Which one of the following is not an igneous rock ?

[amp_mcq option1=”Granite” option2=”Slate” option3=”Basalt” option4=”Gabbro” correct=”option2″]

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The correct option is B.
Igneous rocks are formed from the cooling and solidification of molten rock (magma or lava). Metamorphic rocks are formed from existing rocks (igneous, sedimentary, or other metamorphic rocks) that have been changed by heat, pressure, or chemical reactions. Slate is a metamorphic rock.
Granite is a coarse-grained intrusive igneous rock. Basalt is a fine-grained extrusive igneous rock. Gabbro is a coarse-grained intrusive igneous rock, compositionally similar to basalt. Slate is a fine-grained, foliated metamorphic rock formed by the low-grade regional metamorphism of shale or mudstone.

384. Weathering, mass wasting, erosion and transportation are indicators of

Weathering, mass wasting, erosion and transportation are indicators of which one of the following processes?

[amp_mcq option1=”Denudation” option2=”Endogenetic process” option3=”Diastrophism” option4=”Mountain building” correct=”option1″]

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The correct answer is A) Denudation.
Denudation is the overall process that causes the wearing away of the Earth’s surface by moving water, ice, wind, and waves. It encompasses several processes, including weathering (breakdown of rock), mass wasting (movement of rock and soil downslope under gravity), erosion (removal and transportation of material), and transportation (movement of eroded material).
Endogenetic processes originate within the Earth (like diastrophism and mountain building). Diastrophism is large-scale deformation of the crust. Mountain building (Orogeny) is a specific type of diastrophism. The listed processes (weathering, mass wasting, erosion, transportation) are exogenetic processes acting on the surface.

385. Consider the following statements: 1. Rocks do not remain in their o

Consider the following statements:

  • 1. Rocks do not remain in their original form for long and undergo transformation.
  • 2. Transformation of rocks is caused by weathering, erosion and metamorphic action.

Which of the statements given above is/are correct?

[amp_mcq option1=”1 only” option2=”2 only” option3=”Both 1 and 2″ option4=”Neither 1 nor 2″ correct=”option3″]

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The correct answer is C) Both 1 and 2.
Statement 1 is correct: Rocks are continuously undergoing transformation through the rock cycle (igneous to sedimentary, sedimentary to metamorphic, etc.). They are not static entities. Statement 2 is correct: Transformation is indeed caused by various processes. Weathering and erosion break down rocks, which is a necessary step in the formation of sedimentary rocks. Metamorphic action (heat and pressure) directly transforms existing rocks into metamorphic rocks. These processes are key drivers of the rock cycle.
The rock cycle illustrates how rocks change from one type to another. Weathering, erosion, deposition, compaction, cementation (leading to sedimentary rocks), heat, and pressure (leading to metamorphic rocks), melting, and solidification (leading to igneous rocks) are all processes involved in the transformation of rocks.

386. Which one of the following cities was the first to attain the status o

Which one of the following cities was the first to attain the status of a ‘megacity’?

[amp_mcq option1=”London” option2=”Paris” option3=”New York” option4=”Washington” correct=”option3″]

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The correct answer is C) New York.
While London was the first city to reach a population of 1 million (around 1800), the term ‘megacity’ refers to a metropolitan area with a population exceeding 10 million. The New York metropolitan area is generally considered to be the first in the world to reach a population of 10 million, doing so by the late 1930s or early 1940s, depending on the definition of the metropolitan area used.
London reached the 10 million mark later in the 20th century. Tokyo is often cited as the first Asian megacity, reaching this size later than New York but earlier than London or Paris by most definitions. Washington DC’s metropolitan area reached megacity status even more recently.

387. Which one of the following is likely to be the most prevalent form of

Which one of the following is likely to be the most prevalent form of weathering in hot-tropical desert areas?

[amp_mcq option1=”Mechanical” option2=”Chemical” option3=”Biological” option4=”Leaching” correct=”option1″]

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The correct answer is A) Mechanical.
Hot tropical desert areas are characterized by extreme diurnal (daily) temperature variations and lack of moisture. Mechanical weathering, such as thermal stress (repeated expansion and contraction of rocks due to large temperature swings) and salt crystal growth (where infrequent water evaporates leaving salt crystals that exert pressure), is the dominant form of weathering in these environments.
Chemical weathering requires water, which is scarce in hot deserts, making it less prevalent compared to mechanical processes. Biological weathering can occur but is generally limited by the lack of life forms compared to more humid environments. Leaching is a chemical process requiring water.

388. Snow, sleet and hail are the forms of

Snow, sleet and hail are the forms of

[amp_mcq option1=”precipitation” option2=”condensation” option3=”transpiration” option4=”evaporation” correct=”option1″]

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The correct answer is A) precipitation.
Precipitation is any form of water that falls from clouds and reaches the ground. This includes rain, snow, sleet, hail, and drizzle. Snow, sleet, and hail are specific forms of precipitation.
Condensation is the process by which water vapor in the air changes into liquid water or ice crystals (forming clouds). Transpiration is the process by which moisture is carried through plants from roots to small pores on the underside of leaves, where it changes to vapor and is released to the atmosphere. Evaporation is the process by which water changes from a liquid to a gas or vapor. None of these describe the forms of water *falling* to the ground.

389. Consider the following features about a geographical phenomenon : 1.

Consider the following features about a geographical phenomenon :

  • 1. Torrents of snow and ice roaring down a steep mountain side
  • 2. It is hazardous to skiers and mountaineers
  • 3. It involves a mix of falling, rolling, sliding and flowing of materials

Which of the following phenomena can be identified with the above features?

[amp_mcq option1=”Slump and earthflow” option2=”Avalanche” option3=”Landslide” option4=”Rockslide” correct=”option2″]

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The description of “Torrents of snow and ice roaring down a steep mountain side” is characteristic of an avalanche. Avalanches are rapid mass movements composed mainly of snow and ice. They are a significant hazard in mountainous regions, particularly for skiers and mountaineers. The movement in an avalanche often involves a mix of falling, rolling, sliding, and flowing snow/ice and debris.
An avalanche is a specific type of rapid mass wasting involving snow and ice on a slope.
While landslides can involve rock, debris, or earth, the mention of “snow and ice” specifically points towards an avalanche. Rockslides involve primarily rock material. Slumps and earthflows are types of mass movements involving soil and unconsolidated material, usually less rapid and not primarily composed of snow and ice.

390. Which of the following statements in respect of landslides are correct

Which of the following statements in respect of landslides are correct?

  • These occur only on gentle slopes during rain.
  • They generally occur in clay-rich soil.
  • Earthquakes trigger landslides.

Select the correct answer using the code given below.

[amp_mcq option1=”1 and 2 only” option2=”1 and 3 only” option3=”2 and 3 only” option4=”1, 2 and 3″ correct=”option3″]

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Statement 1 is incorrect because landslides occur primarily on steep slopes where gravity is a significant factor, not only on gentle slopes. While rain is a common trigger, landslides can occur due to other factors as well. Statement 2 is correct as clay-rich soils become unstable when saturated, increasing the risk of landslides. Statement 3 is correct as earthquakes are well-known triggers for landslides due to ground shaking.
Landslides are mass movements occurring on slopes. Their occurrence is influenced by factors like slope angle, soil/rock type, water content, and external triggers like rain or earthquakes.
Factors contributing to landslides include geological factors (weak materials, jointing), morphological factors (steep slopes, erosion), physical factors (intense rainfall, seismic activity), and human factors (deforestation, construction). Clay soils are particularly prone to landslides due to their low shear strength when wet.
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