NCERT Solutions For Class 11 Geography Chapter 6 Landforms and Their Evolution - 2025-26

1. Multiple choice questions.

i. In which of the following stages of landform development, downward cutting is dominated?

• (a) Youth stage
• (b) Late mature stage
• (c) Early mature stage
• (d) Old stage

Answer: (a) Youth stage.

ii. A deep valley characterised by steep step-like side slopes is known as

• (a) U-shaped valley
• (b) Gorge
• (c) Blind valley
• (d) Canyon

Answer: (d) Canyon.

iii. In which one of the following regions the chemical weathering process is more dominant than the mechanical process?

• (a) Humid region
• (b) Limestone region
• (c) Arid region
• (d) Glacier region

Answer: (b) Limestone region.

iv. Which one of the following sentences best defines the term ‘Lapies’?

• (a) A small to medium sized shallow depression
• (b) A landform whose opening is more or less circular at the top and funnel shaped towards bottom
• (c) A landform formed due to dripping water from surface
• (d) An irregular surface with sharp pinnacles, grooves and ridges

Answer: (d) An irregular surface with sharp pinnacles, grooves and ridges.

v. A deep, long and wide trough or basin with very steep concave high walls at its head as well as in sides is known as:

• (a) Cirque
• (b) Glacial valley
• (c) Lateral Moraine
• (d) Esker

Answer: (a) Cirque.

2. Answer the following questions in about 30 words.

i. What do incised meanders in rocks and meanders in plains of alluvium indicate?

Answer: Incised meanders in rocks indicate rejuvenation of rivers, where the river downcuts into bedrock due to uplift or sea-level change. Meanders in alluvial plains indicate lateral erosion and development on gentle gradients, suggesting stabilization and maturity of the river system.

ii. Explain the evolution of valley sinks or uvalas.

Answer: Valley sinks or uvalas evolve when sinkholes and dolines merge due to collapse or slumping of their boundaries. Over time, this forms long, narrow to wide trenches, creating larger depressions in limestone regions characteristic of karst topography.

iii. Underground flow of water is more common than surface run-off in limestone areas. Why?

Answer: Limestone areas have permeable, highly jointed rocks, allowing rainwater to percolate easily and flow underground through bedding planes and joints. This facilitates subsurface drainage, making underground flow more common than surface run-off.

iv. Glacial valleys show up many linear depositional forms. Give their locations and names.

Answer: Linear depositional forms in glacial valleys include moraines (lateral along valley sides, terminal/moraine at glacier ends, medial in the middle), eskers (sinuous ridges in valley floors), and outwash plains at the valley's foot/beyond glacial limits.

v. How does wind perform its task in desert areas? Is it the only agent responsible for the erosional features in the deserts?

Answer: Wind erodes desert surfaces through deflation, abrasion and impact, removing loose particles and sculpting landforms. However, water from rare torrential rains and mass wasting also play important roles in shaping erosional features in deserts.

3. Answer the following questions in about 150 words.

i. Running water is by far the most dominating geomorphic agent in shaping the earth’s surface in humid as well as in arid climates. Explain.

Answer: Running water, through overland flow and river channels, is the chief geomorphic agent shaping the earth’s surface. In humid climates, abundant rainfall ensures streams and rivers actively erode, transport, and deposit materials—forming features like valleys, gorges, meanders, floodplains, deltas, and alluvial fans.

Even in arid climates, rare but intense rainfall creates sheet floods and ephemeral streams that reshape the landscape by weathering rock, removing debris, and creating features such as pediments, alluvial fans, and playas. Over time, running water levels relief, lowers divides, and creates plains of deposition and erosion through its persistent action in different climatic conditions.

ii. Limestones behave differently in humid and arid climates. Why? What is the dominant and almost exclusive geomorphic process in limestone areas and what are its results?

Answer: In humid climates, abundant water promotes intensive solution and deposition (chemical weathering) in limestone, developing distinct karst features like sinkholes, caves, and uvalas. Conversely, in arid climates, limited water reduces solution, making such features rare.

The dominant and almost exclusive process is solution—it dissolves calcium carbonate, leading to erosional features like swallow holes, lapies, dolines, caves, and subsequent depositional features such as stalactites and stalagmites inside caves.

iii. How do glaciers accomplish the work of reducing high mountains into low hills and plains?

Answer: Glaciers sculpt high mountains by eroding through abrasion and plucking, wearing down valleys to form deep, U-shaped troughs and cirques. As glaciers move, they remove debris and lower divides, transporting rocks and sediments. The deposited material forms landforms like moraines, drumlins, eskers, and outwash plains. Over time, relentless movement reduces rugged mountain topography into low, subdued hills and broad plains covered by glacial deposits.

NCERT Solutions for Landforms and Their Evolution (Geography Class 11) – 2025-26

Mastering Landforms and Their Evolution NCERT Solutions is essential for Class 11 Geography success. With stepwise answers to every exercise, you get clarity on major concepts like erosion, deposition, and geomorphic agents impacting Earth’s surface.

Studying NCERT Solutions 2025-26 helps you understand how rivers, glaciers, winds, and groundwater shape landscapes. Keep focusing on definitions, diagrams, and example-based questions to boost marks and strengthen your Geography fundamentals.

Consistent practice of these exercise-based solutions ensures you develop conceptual understanding and exam confidence. Revise regularly, highlight key differences in landforms, and apply learning to real-world examples for top scores in school exams.

CBSE Class 11 Geography Chapter-wise NCERT Solutions

CBSE Class 11 Geography Study Materials