Karnataka 1st PUC Geography Question Bank Chapter 4 Landforms Questions and Answers Solution, Notes by Expert Teacher Priya Verma. Karnataka Class 11 Geography Solution Chapter 4.
There are 2 Parts in Karnataka Class 11 Textbook. Here You will find Part A Fundamentals of Physical Geography’s Chapter 4 Landforms (Geomorphic processes, Weathering, Denudational agents: Work of River).
Karnataka 1st PUC Geography Question Bank Chapter 4 – Landforms Solution
- State – Karnataka.
- Class – 1st PUC / Class 11
- Subject – Geography.
- Topic – Solution / Notes.
- Chapter – 4
- Chapter Name – Landforms.
- Subpart – Geomorphic processes, Weathering, Denudational agents: Work of River.
(I) Answer the following in a word or a sentence each.
(1) What is geomorphic process?
Answer :
Geomorphic process are the continuous changes in the earth’s crust because of natural agents.
(2) Define Diastrophism.
Answer :
Diastrophism is the upward movement of the earth’s crust or any process which makes the crust to move, elevate or build portions of it.
(3) Mention the force responsible for Mass movement.
Answer :
The force responsible for mass movement is gravity.
(4) What is Weathering?
Answer :
Weathering is the process of disintegration and decomposition of rocks.
(5) Name any two factors of Mechanical weathering.
Answer :
Factors responsible for mechanical weathering are temperature, frost, wind, and sea waves.
(6) How does granular disintegration occur?
Answer :
Granular disintegration occurs when rock components react differently to heat and break down into numerous mineral grains.
(7) What is the role of oxygen in Oxidation?
Answer :
Oxygen reacts with the rocks containing iron and produce oxides in the process of oxidation.
(8) Which region is predominant in Carbonation?
Answer :
Carbonation is predominantly found in limestone region.
(9) What is River capture?
Answer :
River capture is a head-ward erosional landform formed by the river. When the source of the river is captured by another major river then it is known as river capture.
(10) How are Ox-bow lakes formed?
Answer :
Oxbow lakes are formed by depositional and erosional action of the river, taking place simultaneously. When the meandering river cuts off from the main river stream it forms an oxbow lake.
(II) Answer the following in two or three sentences each.
(1) State the difference between Endogenic and Exogenic forces
Answer :
Endogenic forces are the internal forces which are usually the land building forces. Whereas exogenic forces are the external forces which acts on the surface of the earth, and they are usually degradational and aggradation forces.
(2) What is Mass movement?
Answer :
Mass movement is the rapid movement of rock debris under the influence of gravity. It includes gravity induced slope material and excludes transportation by any other source like river, wind, glacier etc.
(3) Name any two types of Weathering processes.
Answer :
There are three types of weathering- Mechanical weathering, chemical weathering, and biological weathering.
(4) Distinguish between Oxidation and Hydration.
Answer :
In chemical weathering, the oxygen in rain water reacts with the rocks containing iron and produce iron oxides. This process is known as oxidation. Whereas in hydration rock mineral react with the water and create physical stress on the rocks. As a result, the rocks disintegrate and form powder.
(5) How does Biological weathering take place?
Answer :
Biological weathering takes place by the action of plants, animals, and human beings.
(6) Mention any two agents of denudation.
Answer :
Some important agents of denudation are river, underground water, glaciers, wind, and waves.
(7) What is Canyon? Give example.
Answer :
Canyon is wide, deep, and steep valley with almost vertical walls. It is usually found in arid and semi-arid regions. For example, Grand Canyon of River Colorado in USA.
(8) Distinguish between Meanders and Ox-bow lakes.
Answer :
Meanders are the zigzag movement of rivers which is formed by the depositional action of river. And because of excessive meandering the curved meander cuts off from the mainstream and forms ox bow lakes.
(9) What is Delta? Name any two types of delta.
Answer :
The alluvial deposition on the mouth of the river is known as delta. Some important types of deltas are common delta or arcuate delta and bird foot delta.
(10) Mention the difference between Tributaries and Distributaries.
Answer :
The main river is joined by numerous small rivers which are known as tributaries. And when the river approaches the sea or ocean its speed and gradient get reduced because of which it gets separated into various distributaries.
(III) Answer the following.
(1) What is landform? Explain the different types of geomorphic processes.
Answer :
The natural formation of the rock and the soil on earth is known as landform. It is the natural features of the landscape, natural physical features of the earth’s surface. For example- valley, hills, plateaus, loess plain etc. Formation of these landforms are through various geomorphic processes. Geomorphic processes are classified into two types-
Endogenicforces– The internal forces of the earth which are responsible for the formation of various landforms on the earth are known as endogenic forces. It includes orogenic forces also known as mountain building forces, and epeirogenic forces or continent building forces.
Exogenicforces– The external forces on the earth’s forces which are responsible for formation of various landforms are known as exogenic forces. For example, river, glacier, wind, sea waves etc.
(2) Describe the factors affecting Physical weathering.
Answer :
The process of disintegration of rocks by the action of temperature, frost, wind and sea waves is known as mechanical weathering or physical weathering.
- Temperature– In high temperature rock expands and in low temperature it contracts. This leads to the disintegration of the rocks.
- Frost– In cold regions, because of low temperatures water solidifies into ice in the rocks during the night time and this ice melts during the day. This contraction and expansion of rocks leads to disintegration of rocks.
- Wind– The wind action in desert region carries dust and sand particles which scratches and leads to breaking of rocks.
- Gravitation– Because of gravity the large rocks roll down and rub against each other. Because of this they break up into smaller and finer pieces.
- Seawaves– The sheer action of sea water across the coastal areas causes the breaking of rocks.
(3) Explain chemical weathering with examples.
Answer :
The process of disintegration and decomposition of rocks because of chemical changes is known as chemical weathering. It is classified into four types-
- Oxidation– When the oxygen in rainwater reacts with the iron containing rocks which forms iron oxides. For example, rusting of iron.
- Carbonation– When the rainwater reacts with the carbon dioxide it forms weak carbonic acid, which reacts with the limestone and calcium carbonate. This process is known as carbonation.
- Hydration– When the rock minerals take up excess water which increases the stress within the rocks and makes them disintegrate this process is known as hydration. For example, feldspar and gypsum.
- Solution– When the rainwater dissolves certain rock minerals, this process is known as solution. For example, rock salt, gypsum, potash etc.
(4) Describe the landforms associated to work of river.
Answer :
River is an exogenic force which leads to the formation of various landforms. The river course is divided into three categories-
- The upper course- This is also known as young stage and it is found near the upper source in the mountainous regions. Various landforms are formed in this phase like V-shaped valley, gorge, I shaped valley, canyon, potholes, waterfalls, river capture etc.
- The middle course– It begins when the river enters the plains and plateaus. This is also known as mature stage. In this phase various landforms are created like Meander, ox bow lakes, flood plains, natural levees etc.
● The lower course– In this phase the river reaches its mouth, and the slope is very gentle. Here the speed of the river is very slow, and the deposition work is more prominent. This phase is also known as old stage. Landforms formed in this phase are distributaries, deltas, estuary etc.