Question 1

Q1: Multiple choice questions. (i) Which one of the following processes is a gradational process? (a) Deposition (b) Diastrophism (c) Volcanism (d) Erosio...

Accepted Answer

(d) Erosion The source text defines gradation as "The phenomenon of wearing down of relief variations of the surface of the earth through erosion." While deposition is part of the overall process that levels the earth's surface, erosion is the specific process of wearing down, which is central to th...

Question 2

Q1: (ii) Which one of the following materials is affected by hydration process? (a) Granite (b) Clay (c) Quartz (d) Salts

Accepted Answer

(b) Clay Hydration is a chemical weathering process where minerals absorb water, leading to expansion and decomposition. While the text does not specify which material is affected, clay minerals are known to expand significantly when they absorb water, making them highly susceptible to this process....

Question 3

Q1: (iii) Debris avalanche can be included in the category of: (a) Landslides (b) Slow flow mass movements (c) Rapid flow mass movements (d) Subsidence

Accepted Answer

(c) Rapid flow mass movements The textbook describes mass movements as ranging from slow to rapid and includes creep, flow, slide, and fall. It explicitly mentions that in the Himalayas, "debris avalanches and landslides occur very frequently." Landslides are defined as "relatively rapid and percept...

Question 4

Q2: (iii) What are the various mobile and mighty exogenic geomorphic agents and what is the prime job they perform?

Accepted Answer

The mobile and mighty exogenic geomorphic agents are running water, glaciers (moving ice masses), wind, waves, and currents. Their prime job is to act as a medium to remove, transport, and deposit earth materials. This entire process of wearing down the landscape is known as erosion.

Question 5

Q2: (ii) What are mass movements that are real rapid and perceptible? List.

Accepted Answer

Rapid and perceptible mass movements are generally categorized under landslides. The text lists several types:     Slump    Debris slide    Debris fall    Rockslide *   Rock fall Debris avalanches are also mentioned as frequent, rapid movements.

Question 6

Q2: (iv) Is weathering essential as a pre-requisite in the formation of soils? Why?

Accepted Answer

Yes, weathering is an essential prerequisite for soil formation. The text states that soil formation, or pedogenesis, depends first on weathering. This is because weathering breaks down the parent rock into a fragmented layer called the weathering mantle, which is the basic input material upon which...

Question 7

Q2: Answer the following questions in about 30 words. (i) It is weathering that is responsible for bio-diversity on the earth. How?

Accepted Answer

Weathering is responsible for biodiversity because it breaks down rocks to form the weathering mantle, which is the basis of soil. The text states that forests and vegetation depend on the depth of this mantle. Forests, in turn, support a vast array of animal life, thus creating and sustaining biodi...

Question 8

Q3: (ii) Exogenic geomorphic processes derive their ultimate energy from the sun's heat. Explain.

Accepted Answer

Exogenic geomorphic processes, which include weathering, erosion, and deposition, are driven by energy from the earth's atmosphere, which is ultimately derived from the sun. The sun's heat is the primary engine of the Earth's climate system. Solar energy creates temperature differences across the gl...

Question 9

Q3: (iv) How do you distinguish between the process of soil formation and soil-forming factors? What is the role of climate and biological activity as two...

Accepted Answer

The process of soil formation, or pedogenesis, describes the actual sequence of events that transform parent material into mature soil. As described in the text, this involves the colonization of weathered material by organisms, the accumulation of organic matter (humus), the penetration of roots, a...

Question 10

Q3: (iii) Are physical and chemical weathering processes independent of each other? If not, why? Explain with examples.

Accepted Answer

No, physical and chemical weathering processes are not independent of each other. They often work together, and one process can enhance the effectiveness of the other. The textbook states, "Very rarely does any one of these processes ever operate completely by itself." Physical weathering aids chemi...

Question 11

Q3: Answer the following questions in about 150 words. (i) "Our earth is a playfield for two opposing groups of geomorphic processes." Discuss.

Accepted Answer

The statement that our earth is a playfield for two opposing groups of geomorphic processes refers to the continuous interaction between endogenic (internal) and exogenic (external) forces.  Endogenic Forces: These originate from within the earth and are primarily land-building forces. Processes lik...

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