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Small Scale maps: The Maps drawn on the scale below 1 cm: 15Km or 1:15, 00,000 eg. Atlas and Wall Maps. These maps show broad physical and cultural features.

A map is defined as a symbolical and conventional representation of the earth or a portion fit drawn to scale on a flat surface and bounded by the geographical coordinates as viewed from above.

A scale is the ratio of the distance between two points on the map and their corresponding distance on the ground.

These are the imaginary angular lines drawn parallel to the equator.

A map is defined as a symbolical and conventional representation of the earth or a portion fit drawn to scale on a flat surface and bounded by the geographical co-ordinates as viewed from above.

The science and art of making maps, charts, globes and rile models is known as Cartography.

The Peninsular Plateau is the largest and oldest physiographic division of India. It lies to the south of the Northern Great Plains and covers and area of about 161akh sq km. The elevation of this upland varies from 600 to 90m. This is in inverted triangle shape, with wide base lying in the north and the apex formed in the south, with tilt towards south eat.

It is bounded by the Aravallis in the North West, Bundelkhand plateau in the north, Rajmahal hills in the north east, the Western Ghats in the west and the Eastern Ghats in the east. The highest peak of Peninsular plateau is Anaimudi (2695 m) situated in Annamali hills of Kerala.

On the basis of relief features the peninsular plateau is divided into two main divisions. They are, The Central high lands: This is a smaller region of peninsular plateau situated to the north of the Narmada river. It is slightly tilted towards north. It include the Aravallies, the Malwa plateau, the Vindhya range, the Bundelkhand, the Baghelkhand and Chotanagpur plateau and Rajmahal hills.

The Aravallies runs from north east to south west for about 8900 km between Delhi to Gujarat. It is one of the oldest folded mountains of the world. Its highest peak is Guru Shikar (1722m). It separates Rajasthan- upland and agricultural region. The Aravallis are composed of quatizetes, gneisses and schists.

Rivers like the Luni, Sabarmati and the mahi flow from Aravalli ranges. The Malwa plateau is bordered by the Aravallis in the north and the vindyan range in the south. This plateau has to drainage systems i) Narmada and Mahi towards the Arabian Sea ii) Chambal, Sind, Betwa and Ken towards the Bay of Bengal. ’

The vindyan range extends in ease west direction for about 1050km. The kaimur hills lies in the east of Vindhya range and the Maikala range forms a link between the Vindhya and Satpura ranges.

The Deccan Plateau: this is a triangular plateau situated to the south of the river Tapi or Tapti. The Deccan trap is the crystalline core of the lava effusions forming this plateau are believed to have occurred through a fissure volcano and this region is considered a lava shield. It occupies the areas of Maharashtra, Karnataka, Andhra Pradesh and parts of Chhattisgarh, Odisha and Tamil Nadu.

Eastern Ghats: They form eastern boundary of the Deccan Plateau. They are “separated by the river valleys. The Eastern Ghats stretch to 800 km from Mahanadi valley in the north to Nilgiri hills in the south. Its average height is around 600m.Nallamalla, Kallamalai, B.R.Hills and M.M.Hilis are the important hills of Eastern Ghats. 

The important peaks are Aramakonda, Singaraju, Nimalgiri, Mahendra giri etc. Aramakonda is considered as the highest peak of the Eastern Ghats. These zones are rich in Iron ore, Manganese ore, Limestone, Coal, Mica etc.

Western Ghats: It is also known as Sahyadris. They are almost continuous mountain system running parallel to west coast for about 1600km., from north-west to south direction. The Western Ghats meet the Eastern Ghats in Nilgiri hills.

The Western Ghats form a watershed of the peninsular rivers. Important rivers like the Godavari, Krishna, Kaveri, Sharavati, Periyar etc, rise in this zone. They are sources of hydro¬electricity. They are covered with dense evergreen and monsoon forest and rich bio-diversity zones.

River is an important external agent of denudation on the ever changing face of the Earth.

The work of river is more or less common in all the drainage systems of the world.

The work of river consists of three closely interrelated activities.

1. Erosional work: The process of wearing and taking away the part of rock is known as ‘Erosion’. It depends upon the volume and velocity of water, nature of slope and the nature of rocks. The erosional work of the river is performed in two ways.

a. The Mechanical and 

b. The Chemical erosion. 

There are various landforms associated to erosional work of river.

a. ’V’ Shaped valley: In the mountain course the speed of the river is greater and volume is less. As the water rushes down the steep slopes there is maximum vertical or later erosion. The rapid down cutting or vertical erosion results in the formation of ‘V’ shaped valley. 

b. Gorge: A deep and narrow valley with steep rocky sides in the river course is known as ‘Gorge’. They are formed by the regular vertical cutting by the rivers in the valleys eg. Narmada gorge. 

c. I shape valley: A vey steep, deep river valley formed by the river, looking like ‘I’, is called T Shaped valley. These are very deep compared to gorges. 

d. Canyon: It is a wide, deep and steep valley almost with vertical walls like feature found in the arid or semi arid regions is called ‘Canyon’ eg. Grand Canyon of River Colorado in USA.

e. Potholes: These are the small depressions in the rocky beds of other river valley. They are formed by corrosion. Pebbles, sand and small rocks carried by the river swirled around on the river bed. This action erodes the rock on the river bed forming potholes. 

f. Waterfalls: Huge volume of water falling from a great height along the course of a river is called “Waterfalls’. They are formed when the hard and soft rocks come in the way of flowing river. The soft rock gets eroded faster and hard rock does not erode easily. Therefore huge amount of water falls from great height and creates waterfalls. Eg. The Jog falls, The Angel falls, The Victoria falls. 

g. River Capture: It is formed mainly due to head-ward erosion by the river near its source. When the source of a river is captured by another major and strong river it is called‘River Capture’.

2. Transportational work: The process of carrying away the eroded materials is known as ‘Transportation’. The rock materials and eroded particles carried by a river is called its Load. The transportation capacity of a river is based on velocity of water, volume of water, load, slope, smooth valley floor etc.

The major landforms associated with the transportational work of the river are,

a. Alluvial fans: The term alluvium refers to the debris transported and deposited by rivers. When the fast flowing river enters the plateau or plain region, it experience sudden decline in gradient and obstruction in its path. Due to obstruction of the river spreads and deposits many of its light materials in fan shape known as ‘alluvial fans’. 

b. Alluvial cones: In the plateau and foot hill region when the river spreads out, the eroded materials carried by the river is deposited in conical shape called ‘Alluvial cones’. 

3. Depositional work: The process of carrying and accumulating the eroded materials by the river at the lower course is called ‘deposition’. In the lower course due to gentle slope the river slows down and deposits most of its materials on the banks, course and the mouth.

The important landforms resulting from depositional work of the river are,

a. Meanders: In the lower course, river flows slowly in zig zag or curved manner due to smaller obstruction in its path. A curve or loop formed by the river in its path is called ‘Meander’. When the river course formed by such crescent shaped loops due to continuous lateral deposition it is called meandering course.

b. Ox-bow Lakes: The ox-bow lakes are formed by depositional and erosional actions taking place simultaneously and they are a result of excessive meandering. The River which flows through the shorter route leaving the curve of the meander cut off and crescent shaped lake is formed known as ‘Ox-bow lakes’. 

c. Flood Plains: When the river is in floods the water over flows on its bank and spreads in the surrounding regions. The silt carried by the water gets deposited in these areas and creates flat plains on both the banks of the rive known as ‘Flood Plains’.

d. Delta: A triangular shaped alluvial deposition forced at the mouth of the river is called ‘Delta’. Important types of deltas are a. Arcuate or Common delta b. Bird-foot delta 

e. Distributaries: As the river approaches the sea or Ocean, due to reduction in gradient, joining of tributaries, its volume increases, speed decreases hence, the river begins to break up into a number of branches from the main river called ‘Distributaries’. 

f. Estuary: Estuaries are the tidal mouth of a riverhaving a narrow, gradually widening lay at the mouth. In Estuary River water is mixed with sea water. Eg. The Narmada estuary, The Kali estuary.

The peninsular region of India has the largest forest cover with around 57% of the total forest area.

According to geo-climatic conditions, forests are classified into: 

a. Evergreen Forests: These forests are found in the regions of heavy rainfall and high temperature. Tall umbrella shaped trees with dense assemblage is a prominent feature of this forest. The eve 4rgree forest always looks green because various species of trees are found here and they shed leaves in different seasons.

The hardwood trees, rose wood, white cedar, toon, gurjan, chaplash, ebony, Mahogany, canes, bamboo, shisham etc. These are found in North-east India, Western Ghats, Andaman and Nicobar islands, parts of Assam and some areas of Himalayan foot hills.

b. The Deciduous forests: The deciduous forest covers a wide range of rainfall regimes. The trees of these forests seasonally shed their leaves. The Indian deciduous forest is found in a range of landscapes from the plains to the hills. These forests provide shelter to most endangered wild life in the country, such as the Tiger, Asian Elephant, Bison, Gaur etc. The deciduous forest are two types

(i) Moist Deciduous forests: The moist deciduous forests are found in wet regions, receiving annual rainfall between 100cm to 200cam and temperature of 25° C to 30° C. The trees of these forests shed their leaves during spring and early summer. They are found on the eastern slopes of the Western Ghats, Chota Nagpur Plateau, the siwaliksetc. 

(ii) The Dry Deciduous Forests: The dry deciduous forest are found I the areas where annual rainfall is between 50cm to 150 cm and temperature of 25° C to 30° C. Sal is the most significant tree found in this forest. Varieties of acacia and bamboo are also fund here. These forests are found in areas of central Deccan plateau, South-east of Rajasthan, Punjab, Haryana and parts of Uttar Pradesh and Madhya Pradesh.

(iii) The mountain forests: As the name indicates these forests are confined to the Himalayan region, where the temperature is less compared to other parts of the country. The trees in this forest are cone shape with needle like leaves. The important trees are oak, fir, pin e spruce, silver fir, deodhar, devdar, juniper, picea chestnut etc. They provide softwood for making country boats, packing materials and sport articles.

c. The Desert forests: These forests are found in the areas of very low rainfall. Thorny bushes, shrubs, dry grass, acacia, cacti and babul are the important vegetation found in these forests. The Indian wild date known as ‘Khejurs”, is common in the deserts. They have spine leaves, long roots and thick fleshy stems in which they store water to survive during the long drought. These vegetations are found in Rajasthan, Gujarat, Punjab and Haryana.

d. The Mangrove Forests: These forests occur along the river deltas (Ganga, Mahanadi. Godavari and Krishna) of eastern coast and also concentrated in the coastal areas of Katchch, Kathiawar, and Gulf of Khambar. The mangrove forests in the Ganga delta are called Sunder bans because, they have extensive growth of Sundari trees. The trees in these forests are hard, durable and are used in boat making and as fuel. In the recent years mangrove vegetation is being grown I the coastal areas to control effects of tidal waves and coastal erosion.

Rock refers to the hard and resistant materials of the earth’s crust. But scientifically rock includes even soft and loose materials like chalk, clay, etc. So, rock refers to any solid materials, hard or soft of which the crust of the earth is formed. All rocks do not have the same chemical composition. But minerals have their own chemical compost in and physical prosperities. The earth’s crust is made up of various types of rocks

Types of Rocks: Rocks can be classified into three major groups on the basis of their origin or mode of formation. They are:

A. Igneous rocks: The term Igneous is derived from the Latin word “Ignis”, means fire. Thus the igneous rocks are formed by the cooling and solidification of molten material which is called magma. Igneous rocks are also called primary rocks, because they were the firs to be formed. As they are the rocks from which all other types of rocks are derived, they are also called parent rocks.

Igneous rocks are commonly classified on the basis of mode of formation into two major types. 

1. Intrusive rocks 

2. Extrusive rocks.

1. Intrusive rocks: The magma cannot escape out to the earth’s surface, it cols slowly inside the earth’s crust and hardens into rock. This type of rock is known as Intrusive Igneous rock. E.g. Granite and dolerite. These rocks can be divided into two type’s 

a. Plutonic rocks and 

b. Hybabyssal rocks.

• Plutonic rocks: The rocks which are formed due to cooling of magma at great depth inside the earth are called Plutonic igneous rocks. 
• Hybabyssal rocks: These are intermediate rocks between the extruded volcanic rocks and the deep plutonic rocks. They are formed due to cooling and solidification of magma in cracks, pores, crevices etc.

II. Extrusive rocks: Rocks formed by cooling and solidification of lava on the surface of the Earth is called extrusive igneous rocks. E.g. Basalt.

B. Sedimentary Rocks: These rocks which are formed due to aggregation and compactness of sediments are known as sedimentary. In other words, sedimentary rocks are formed bye day the deposition of sediments derived form older rocks, planets and animals remains by river, winds, glaciers etc and these sediments are hardened into rocks by pressure. As they are formed by the consolidation of sediments. They are called sedimentary rocks. They are also called stratified rocks,

a. Mechanically-formed rocks: The rock which have been formed form the accumulation of rock materials, derived form other rocks and have been cemented together are known as “ Mechanically formed rocks.” The mechanically formed rocks consist of sediments which have been carried and deposited by rivers, glaciers, winds or waves and cemented together with clay or line. On the basis of rock materials. These rocks can be divided into three main categories. They are: Rudaceous rocks, Arernaceous rocks and Argilious rocks. 

b. Chemically formed rocks: The chemical often settle down and hardened to form rocks known as chemically formed rocks. For example: Gypsum and rock salt, running water dissolves and carries chemicals and where evaporation takes place, these chemicals are deposited at the mouth of springs, caves or caverns or in lakes. Rock salt and gypsum are formed form deposit of salt in strata on the beds of lakes.

c. Organically formed rocks: Organic rocks are formed form the remains of organisms, i.e. of animals and plants. Examples: coal, limestone etc. On the basis of lime and carbon content, organically formed rocks can be divided into two kinds, namely

• Calcareous rocks: Calcareous rocks are formed mostly from the remains of living organisms. These rocks contain calcium carbonate or lime. They include limestone and chalk. They are porous and soluble.
• Carbonaceous rocks: These are formed due to the transformation of vegetative matter. Under the impact of heat and pressure the remains of plants are turned into hard layers. E.g. coal.

C. Metamorphic rocks: Rock which has been changes either in form or in composition without disintegration is called metamorphic rocks. These rocks are metamorphosed form igneous sedimentary rocks. Igneous and sedimentary rocks may undergo chemical and physical changes because of pressure and heat and form metamorphic rocks. The intense heat and pressure in the earth’s curst alters the composition and appearance of rocks completely or partially to produce a new type of rocks.In this manner metamorphic rocks are formed. Marble, Diamond, Quartzite, Ruby, Emerald are the examples of metamorphic rock.

In this human vision defect a person can see near by object clearly but he can not see distant object clearly.

It can be corrected by using a concave less of suitable focal length.

River is an important external agent of denudation on the ever changing face of the Earth. The work of river is more or less common in all the drainage systems of the world. 

The work of river consists of three closely interrelated activities.

1. Erosional work: The process of wearing and taking away the part of rock is known as ‘Erosion’. It depends upon the volume and velocity of water, nature of slope and the nature of rocks. The erosional work of the river is performed in two ways.

a. The Mechanical and 

b. The Chemical erosion. 

There are various Iandforms associated to erosional work of river.

a. ’V’ Shaped valley: In the mountain course the speed of the river is greater and volume is less. As the water rushes down the steep slopes there is maximum vertical , or later erosion. The rapid down cutting or vertical erosion results in the formation of ‘V’ shaped valley. 

b. Gorge: A deep and narrow valley with steep rocky, sides in the river course is known as ‘Gorge’. They are formed by the regular vertical cutting by the rivers in the valleys eg. Narmada gorge.

c. I shape valley: Avey steep, deep river valley formed by the river, lookinglike T, is called ‘I’ Shaped valley. These are very deep compared to gorges. 

d. Canyon: It is a wide, deep and steep valley almost with vertical walls like feature found in the arid or semi arid regions is called ‘Canyon’ eg. Grand Canyon of River Colorado in USA. 

e. Potholes: These are the small depressions in the rocky beds of other river valley. They are formed by corrosion. Pebbles, sand and small rocks carried by the river swirled around on the river bed. This action erodes the rock on the river bed forming potholes. 

f. Waterfalls: Huge volume of water falling from a great height along the course of a river is called “Waterfalls’. They are formed when the hard and soft rocks come in the way of flowing river. The soft rock gets eroded faster and hard rock does not erode easily. Therefore huge amount of water falls from great height and creates waterfalls. Eg. The Jog falls, The Angel falls, The Victoria falls.

g. River Capture: It is formed mainly due to head-ward erosion by the river near its source. When the source of a river is captured by another major and strong river it is called‘River Capture’.

2. Transportational work: The process of carrying away the eroded materials is known as ‘Transportation’. The rock materials and eroded particles carried by a river is called its Load. The transportation capacity of a river is based on velocity of water, volume of water, load, slope, smooth valley floor etc.

The major landforms associated with the transportational work of the river are:

a. Alluvial fans: The term alluvium refers to the debris transported and deposited by rivers. When the fast flowing river enters the plateau or plain region, it experience sudden decline in gradient and obstruction in its path. Due to obstruction of the river spreads and deposits many of its light materials in fan shape known as ‘alluvial fans’. 

b. Alluvial cones: In the plateau and foot hill region when the river spreads out, the eroded materials carried by the river is deposited in conical shape called ‘Alluvial cones’.

3. Depositional work: The process of carrying and accumulating the eroded materials by the river at the lower course is called ‘deposition’. In the lower course due to gentle slope the river slows down and deposits most of its materials on the banks, course and the mouth.

The important landforms resulting from depositional work of the river are: 

a. Meanders: In the lower course, river flows slowly in zig zag or curved manner due . to smaller obstruction in its path. A curve or loop formed by the river in its path is called ‘Meander’. When the river course formed by such crescent shaped loops due to continuous lateral deposition it is called meandering course.

b. Ox-bow Lakes: The ox-bow lakes are formed by depositional and erosional actions taking place simultaneously and they are a result of excessive meandering. The River which flows through the shorter route leaving the curve of the meander cut off and crescent shaped lake is formed known as‘Ox-bow lakes’. 

c. Flood Plains: When the river is in floods the water overflows on its bank and spreads in the surrounding regions. The silt carried by the water gets deposited in these areas and creates flat plains on both the banks of the rive known as ‘Flood Plains’.

d. Delta: A triangular shaped alluvial deposition forced at the mouth of the river is called ‘Delta’. Important types of deltas are

a. Arcuate or Common delta 

b. Bird-foot delta

e. Distributaries: As the river approaches the sea or Ocean, due to reduction in gradient, joining of tributaries, its volume increases, speed decreases hence, the rivet begins to break up into a number of branches from the main river called ‘Distributaries’. 

f. Estuary: Estuaries are the tidal mouth of a river having a narrow, gradually widening lay at the mouth. In Estuary River water is mixed with seawater. Eg. The Narmada estuary, The Kali estuary.

The cyclic mevement of water between the atmosphere and the earth’s sunface is called ‘Hydrological cycle’. 

A transformer is a device used to change AC voltage by using the principle of mutual induction.

1. Loss due to flux leakage 

2. Loss due to eddy current

The peninsular region of India has the largest forest cover with around 57% of the total forest area. According to geo-climatic conditions, forests are classified into:

a. Evergreen Forests: These forests are found in the regions of heavy rainfall and high, temperature. Tail umbrella shaped trees with dense assemblage is a prominent feature of this forest. The eve4rgree forest always looks green because various.species of trees are found here and they shed leaves in different seasons. The hardwood trees, rose wood, white cedar, toon, gurjan, chaplash, ebony, Mahogany, canes, bamboo, shisham etc. These are found in North-east India, Western Ghats, Andaman and Nicobar islands, parts of Assam and some areas of Himalayan foot hills.

b. The Deciduous forests: The deciduous forest covers a wide range of rainfall regimes. The trees of these forests seasonally shed their leaves. The Indian deciduous forest is found in a range of landscapes from the plains to the hills. These forests provide shelter to most endangered wild life in the country, such as the Tiger, Asian Elephant, Bison, Gaur etc. The deciduous forest are two types ‘ 

(i) Moist Deciduous forests: The moist deciduous forests are found in wet regions, receiving annual rainfall between 100 cm to 200cam and temperature of 25° C to 30°C. The trees of these forests shed their leaves during spring and early summer, They are found on the eastern slopes of the Western Ghats, ChotaNagpur Plateau, the siwaliksetc.

(ii) The Dry Deciduous Forests: The dry deciduous forest are found I the areas where annual rainfall is between 50cm to 150 cm and temperature of 25° C to 30° C. Sal is the most significant tree found in this forest. Varieties of acacia and bamboo are also fund here. These forests are found in areas of central Deccan plateau, South-east of Rajasthan, Punjab, Haryana and parts of Uttar Pradesh and Madhya Pradesh.

(iii) The mountain forests: As the name indicates these forests are confined to the Himalayan region, where the temperature is less compared to other parts of the country. The trees in this forest are cone shape with needle like leaves. The important trees are oak, fir, pin e spruce, silver fir, deodhar, devdar, juniper, picea chestnut etc. They provide softwood for making country boats, packing materials and sport articles.

c. The Desert forests: These forests are found in the areas of very low rainfall. Thorny bushes, shrubs, dry grass, acacia, cacti and babul are the important vegetation found in these forests. The Indian wild date known as ‘Khejurs”, is common in the deserts. They have spine leaves, long roots and thick fleshy stems in which they store water to survive during the long drought. These vegetations are found in Rajasthan, Gujarat, Punjab and Haryana.

d. The Mangrove Forests: These forests occur along the river deltas (Ganga, Mahanadi, Godavari and Krishna) of eastern coast and also concentrated in the coastal areas of Katchch, Kathiawar, and Gulf of Khambar. The mangrove forests in the Ganga delta are called Sunder bans because, they have extensive growth of Sundari trees. The trees in these forests are hard, durable and are used in boat making and as fuel. In the recent years mangrove vegetation is being grown in the coastal areas to control effects of tidal waves and coastal erosion. 

Soil is the minute or finer rock particles found on the surface of the Earth. It is formed naturally, due to the weathering of rocks, under the influence of climate. 

The main types of soil in India are: 

a. Alluvial soil: This soil is formed by depositional work of rivers and they are mainly found in the flood plains and deltas. Alluvial soil covers largest geographical are in the country. They are mainly distributed in the river plains of the Ganga, Brahmaputra and the Indus. Uttar Pradesh has the largest area under alluvial soil. It is also found in the deltas of east flowing rivers. Alluvial soils are classified into two types.

b Bhangar: Older alluvium, coarse and pebble like in nature, found at the lower depths of the plain. (b) Khadar: New alluvium, finer in nature, found in the low lying flood plains and rich in fertility

1. Black soil: The black soils covered more area in peninsular plateau. This soil is also called ‘Cotton soil’ or “Regur soil”. It is derived from the weathered basalt rocks. This soil holds water from long period and become hard whenever it is dry. It is lightblack to dark-black in colour. Maharashtra and Gujarat Madhya Pradesh, Karnataka, Andhra Pradesh and Tamilnadu. Black soils are good for Cotton, Sugarcane, Tobacco, Pulses, Millets, Citrus fruits, etc.

2. Red soil: This soil is formed by the weathered granite rocks. It is red in colour and rich in ferrous content. Red soil covers the second largest area in the country. Largest parts of peninsular region are covered with red soil. TamilNadu has the largest distribution of this soil in the country. Rice, Ragi, Jowar, Groundnut, Tobacco, Millets are the major crops cultivated in this soil.

3. Laterite soil: The hot and humid tropical regions of India are rich in laterite soil. This soil is derived from the fragmentation and disintegration of rocks in the mountain ranges. It is mainly found in the Western Ghats, parts of Eastern Ghats and Northeastern hills of India. Plantation crops like Tea, coffee, Rubber, Cashew nut are cultivated in this soil. 

4. Desert soil: This soil is also called arid soil. They are mainly found in the desert and semi-desert regions of Western and North western parts of India. This soil has the least water holding capacity and humus content. Generally it is not suitable for cultivation of crops. This soil is mainly found in Rajasthan, parts of Gujarat and Haryana. With water facility crops like Bajra, Pulses and Guar are cultivated in this soil.

5. Mountain Soil: The Himalayan mountain valleys and hill slopes are covered with Mountain or Forest soil. It is found in the mountain slopes of Jammu and Kashmir, Himachal Pradesh, Utarkhand regions, Crops like Tea, Almond, saffron are cultivated in this soil.

A transformer is a device used to change AC voltage by using the principle of mutual induction. 

1. Loss due to flux leakage 

2. Loss due to eddy current

When discrimination is made on the basis of gender denying equal opportunities to the fairer sex, it is called gender based inequality.

The process of disintegration and decomposition of rocks is known as “Weathering”

There are three types of weathering 

1. Mechanical weathering 

2. Chemical weathering 

3. Biological weathering 

1. Mechanical weathering: The disintegration of rocks by mechanical way and without any chemical changes is called “Mechanical weathering”. It is also called “physical weathering”. 

The process of Mechanical w eathering is in various forms, depending the types of rock. They are:

• Block disintegration: Due to temperature variation, there is continuous expansion and contraction in the rocks causing tension and stress. Later these rocks disintegrate into blocks known as “Block Disintegration”. 
• Granular disintegration: Rocks consist of several types of minerals and these minerals react differently to heat. As a result, the rocks break into different mineral grain known as “Granular Disintegration”. 
• Exfoliation: Due to the heat of the Sun, outer surfaced of rocks gets heated up, but inside it remains almost cool. This makes the rock to expand and crack. The thin layer of rocks peels off, like the peeling of an onion. This process is Galled “Exfoliation”.

2. Chemical weathering: Disintegration and Decomposition of rocks by chemical processes is called “Chemical weathering”.

In this process secondary or new minerals are developed from the original minerals of the rocks. The rain water and atmospheric gases are the main agents of chemical weathering. It is very common in humid regions.

There are four types of chemical weathering process. They are; 

• Oxidation: The rain water with oxygen reacts on rocks containing iron and produce oxides. This chemical reaction is known as “oxidation”. The common process of rusting of iron is an example of oxidation. 
• Carbonation: The rain water with carbon-di-oxide becomes a weak carbonic acid andit reacts with calcium carbonate or limestone to form calcium bicarbonate, which dissolves easily. This process is called “Carbonation”. It is very active in limestone regions. . 
• Hydration: The rock minerals take up water the increased volume creates physical stress within the rock. As a result certain minerals like feldspar and gypsum are reduced into powder. This process is called “Hydration”. 
• Solution: The rain water is able to dissolve some of the soluble minerals, such as rock-salt, gypsum, potash. This process is called “Solution”.

3. Biological weathering: The disintegration of rocks caused by plants, animals and human beings is called “Biological Weathering”.

1. Plants: The roots of the plant grow through soil and in the cracks of rocks to find water and minerals. As the roots grow deep in the rock they widen and disintegrate the rocks. This process is most prominent in thick forests and vegetative regions.

2. Animals: The burrowing animals like rats, rabbits, ants, earthworms and termites influence in the breaking up of rocks and make passages below the ground. The seepage of air and water through these passage results in rapid weathering of rocks. 

3. Human beings: Human beings play an important role weathering of rocks, through activities like agriculture, mining quarrying, oil drilling, deforestation etc.

The Himalayan Rivers or North Indian Rivers: These rivers take birth in Himalayan Mountains by glaciers and flow’s throughout the year (perennial). There are three main river systems in the Himalayan rivers. 

They are the Indus, the Ganga and the Brahmaputra.

1. The Indus river system: The Indus is one of the most important river systems of India. It rises near Mt. Kailash (6714m), has a length of2880km, of which 709 km lies in India. It flows through narrow gorges between Ladakh and Zaskar ranges in the North West direction in Jammu & Kashmir. It is one of the oldest river systems of the world. Major part of its course and catchment area are in Pakistan. The main tributaries are Jhelum, Chenab, Ravi, Beas and Sutluj.

2. The Ganga: The Ganga is the longest (2500Km) and the largest river system of the country. It is generally called, the ‘National river’ of India. The Ganga has two head streams-the Bhagirathi and the Alakananda. The Bhagirathi takes it is birth in Gangothri and Alakananda rises near Badrinath in Garhwal Himalayas. These two meet at Devaprayag, and continue to flow as the Ganga, after flowing across the Himalayas; the Ganga enters the Great. Plains at haridwar.

From Haridwar it flows towards south an south east up to Mirzapur. It continues to flow’ eastwards in the Gangetic plains of Bihar and West Bengal and enters Bangladesh, where it joins the Brahmaputra and become padma, and finally flow’s into Bay of Bengal. The important tributaries of Ganga are Ramganga, Ghagra, Gandak, Gomati, Bagmati, Kosi, Yamuna, Chambal, Betwa, sone, ken, damodar etc.

3. The Brahmaputra river system: It rises at Manasarovar lake (chanmyandung). In Tibet it is known as Tsangpo. It enters Aruncal Pradesh and is known as Brahmaputra. It joins. Ganga at Golunde (Bangladesh). The total length it flows is 2900km. and only 885km. in India. In Bangladesh it is called Meghana.

1. Used in LASIK eye surgery 

2. UV lamps are used to kill germs in water purifiers 

3. Disinfection for virus and bacteria. 

4. To produce photo electric current in Burglar alarm.

Collector Region:

1. Moderately doped

2. Large in size 

3. Collects charge carriers 

Emitter region:

1. Heavily doped 

2. Moderate in size 

3. Emits charge carriers.

A biosphere Reserve is a unique and representative ecosystem of terrestrial and coastal areas .The regions surrounding the biosphere reserves would be utilized for the research and experimentation in developing forest and other products.

The Man and the Biosphere Programme (MAB) of UNESCO was established in 1971 to promote interdisciplinary approaches to management, research and education in ecosystem conservation and sustainable use of natural resources. Eight of the eighteen biosphere reserves are a part of the world network of Biosphere reserves, based on the UNESCO man and the Biosphere Programme list.

The objectives of Biosphere reserves: 

• Conservation of biodiversity and ecosystem. 
• Association of environment with development. 
• International network for research and monitoring.

Mahatma Gandhiji, VallabhaBhai Patel.

This is the region all along the Indian coastline, lying between the coast and the mountain ranges of the peninsular plateau. India has 6100 km from Gujarat inn the west to West Bengal in the east. The average width is 10-25 kms. The coastal plain of India is divided into two parts.

The West Coastal plains: It is extends between the Arabian Sea and the Western Ghats. It is narrower than the east coastal plains, stretching to a length of about 1400km and width of 10 to 80km from the Rann of katchchh to kanyakumari. The west coastal plains have Gujarat, Konkan, Karnataka and Malabar Coasts.

The Gujarat Coast comprises of Rann of Kachchh and Cambay coasts. It is formed by the alluvial deposits of Sabarmati, Mahi, Luni and other small streams. Gujarat has the longest coast line in India.Kandla and okha are famous sea ports and alang is the biggest ship breaking centre. It produces highest salt in the country.

Konkan Coast lies to the south of Gujarat coast and extends line which provides suitable site foniatural seaports. Eg: Mumbai, Navasheva, Marmagoa, Karwar, New Mangalore etc., this coast records highest coastal erosion. It is very rich in Petroleum and natural gas. Karnataka coast: it is a part of Konkan coast. It extends from karwar in the north to Mangalore in the south. It is the narrowest part of west coastal plains. Karwar and New Mangalore are important ports in this belt. Sea Bird, the naval base near Karvvar is the largest naval base in India.

The Malabar Coast extends from Mangalore to Kanvakumari, Sand dunes, lagoons and backwaters are the important features of this coast. Cochin or Kochi is the biggest seaport in this coast. Backwaters of Kerala facilitate navigation and tourists enjoy travelling though small country boats. The first south west monsoon rainfall is received in this coast.

East coastal Plains: It lies between the Eastern Ghats and the Bay of Bengal stretching from the delta of Hooghly in the North to Kanvakumari in the south. Compared to the west coastal plains the east coastal plains are broader.

The Utkal Coast: It is the coastal plain of Orissa state. It extend for about 400kmms, north from Subarnarekha river to south of the Rushikulya river. It has a chilka lake, which is the largest salt water lake in India, Para deep is the important horbour located here.

Coromandel Coast: The southern part of east coast is known as the Coromandel Coast. It gets more rainfall from the north east monsoons and it is highly affected by cyclones. The oldest harbor Chennai located here.

a. The Ganga basin: The badly affected states of the Ganga basin are U.P, Bihar and West Bengal. Besides the Ganga River, Sarada, Gandak and Ghagra cause flood in Eastern part of U.P. The Yamuna is famous for flooding Haryana, U.P and Delhi. Bihar experiences massive and dangerous flood every year by the Kosi. Rivers like the Mahanadi, Bhagirathi and Damodar also cause floods.

b. The Brahmaputra basin: The Brahmaputra along with its tributaries floods the areas of Assam and North West Bengal regions.

c. The Central India and Peninsular river basin: In odisha spilling over of river banks by the Mahanadi, Baitarnika and Brahmani causes havoc. Southern and central India experiences floods caused by the Narmada, Godavari, Tapti and Krishna during heavy rainfall. Cyclonic storms in the deltaic regions of the Godavari, Mahanadi and the Krishna flood the coastal regions of Andhra Pradesh.

On the basis of severity of droughts, India can be divided into three drought prone areas. 

a. The Extreme drought prone areas: This is the most important drought prone areas of the country which has been recording continuous drought for many years. The regions are western parts of Rajasthan, Kutch regions of Gujarat and semi-arid regions of Western and North western parts of India.

b. The Severe drought prone areas: This is the second important drought prone areas of the county. The eastern parts of Rajasthan, western parts of Madhya Pradesh, Parts of Maharashtra, interior parts of Andhra Pradesh. North and northeastern parts of Karnataka and Tamil nadu.

c. The Moderate drought prone areas: This region is mainly found in regions of U.P, parts of Gujarat, Maharashtra, Jharkhand, Tamil Nadu and interior parts of Karnataka.

1. Terrorist And Disruptive Activities Prevention t Act(TADA)in 1987. 

2. Prevention Of Terrorism Act [POTA] in 2001.

• The ‘Non-Tax Revenue’ of the Government are –
• Profit earned by the Reserve Bank of India 
• Profit generated by the Indian Railways 
• Revenue generated by the Departments of Post and Telecommunications 
• Revenue generated by the public sector industries 
• Revenue generated by the coins and mints 
• Various types of fees and penalties etc.

On the International basis the globe has been divided into 24 time zones (each of 15 longitudes).

In every zone local time of the middle longitude (divided by 7° 30’) is taken as standard time of the entire zone. Because 82 ’/2 ° E is well divisible by 7° 30’. A standard adopted by almost all the countries ofthe world while they selected a Standard meridian for their respective countries.

• Terrorism puts pressure on a government. 
• Terrorism creates a lot of loss for individuals as well as communities. 
• Terrorism creates psychological pain and influences the cultural aspects negatively 
• Terrorism creates panic and violence and fear in people. 
• The Government of India now created special elite force to tackle terrorism.

• India is predominantly an agricultural country. 
• 65% of people depend on agriculture. 
• Main source of livelihood 
• Main source of food, fodder and raw material for animals and industries. 
• Supports tertiary sectors – trade, transport, booking, insurance. 
• Influences political and social situtation of India. 
• Supports Industries.

River is an important external agent of denudation on the ever changing face of the Earth. The work of river is more or less common in all the drainage systems of the world. 

The work of river consists of three closely interrelated activities.

1. Erosional work: The process of wearing and taking away the part of rock is known as ‘Erosion’. It depends upon the volume and velocity of water, nature of slope and the nature of rocks. The erosional work of the river is performed in two ways.

a. The Mechanical and 

b. The Chemical erosion.

There are various Iand forms associated to erosional work of river.

a. ’V’ Shaped valley: In the mountain course the speed of the river is greater and volume is less. As the water rushes down the steep slopes there is maximum vertical , or later erosion. The rapid down cutting or vertical erosion results in the formation of ‘V’shaped valley.

b. Gorge: A deep and narrow valley with steep rocky, sides in the river course is known as ‘Gorge’. They are formed by the regular vertical cutting by the rivers in the valleys eg. Narmada gorge.

c. I shape valley: Avey steep, deep river valley formed by the river, lookinglike T, is called ‘I’ Shaped valley. These are very deep compared to gorges. 

d. Canyon: It is a wide, deep and steep valley almost with vertical walls like feature found in the arid or semi arid regions is called ‘Canyon’ eg. Grand Canyon of River Colorado in USA.

e. Potholes: These are the small depressions in the rocky beds of other river valley. They are formed by corrosion. Pebbles, sand and small rocks carried by the river swirled around on the river bed. This action erodes the rock on the river bed forming potholes. 

f. Waterfalls: Huge volume of water falling from a great height along the course of a river is called “Waterfalls’. They are formed when the hard and soft rocks come in the way of flowing river. The soft rock gets eroded faster and hard rock does not erode easily. Therefore huge amount of water falls from great height and creates waterfalls. Eg. The Jog falls, The Angel falls, The Victoria falls.

2. Transportational work: The process of carrying away the eroded materials is known as ‘Transportation’. The rock materials and eroded particles carried by a river is called its Load. The transportation capacity of a river is based on velocity of water, volume of water, load, slope, smooth valley floor etc.

The major landforms associated with the transportational work of the river are:

a. Alluvial fans: The term alluvium refers to the debris transported and deposited by rivers. When the fast flowing river enters the plateau or plain region, it experience sudden decline in gradient and obstruction in its path. Due to obstruction of the river spreads and deposits many of its light materials in fan shape known as ‘alluvial fans’. 

b. Alluvial cones: In the plateau and foot hill region when the river spreads out, the eroded materials carried by the river is deposited in conical shape called ‘Alluvial cones’. 

3. Depositional work: The process of carrying and accumulating the eroded materials by the river at the lower course is called ‘deposition’. In the lower course due to gentle slope the river slows down and deposits most of its materials on the banks, course and the mouth. 

The important landforms resulting from depositional work of the river are:

a. Meanders: In the lower course, river flows slowly in zig zag or curved manner due . to smaller obstruction in its path. A curve or loop formed by the river in its path is called ‘Meander’. When the river course formed by such crescent shaped loops due to continuous lateral deposition it is called meandering course. 

b. Ox-bow Lakes: The ox-bow lakes are formed by depositional and erosional actions taking place simultaneously and they are a result of excessive meandering. The River which flows through the shorter route leaving the curve of the meander cut off and crescent shaped lake is formed known as‘Ox-bow lakes’. 

c. Flood Plains: When the river is in floods the water overflows on its bank and spreads in the surrounding regions. The silt carried by the water gets deposited in these areas and creates flat plains on both the banks of the rive known as ‘Flood Plains’. 

d. Delta: A triangular shaped alluvial deposition forced at the mouth of the river is called ‘Delta’. Important types of deltas are 

a. Arcuate or Common delta 

b. Bird-foot delta

e. Distributaries: As the river approaches the sea or Ocean, due to reduction in gradient, joining of tributaries, its volume increases, speed decreases hence, the rivet begins to break up into a number of branches from the main river called ‘Distributaries’. 

f. Estuary: Estuaries are the tidal mouth of a river having a narrow, gradually widening lay at the mouth. In Estuary River water is mixed with seawater. Eg. The Narmada estuary, The Kali estuary.

The season of Retreating Monsoon is the period of Transition. During the period of transition low pressure of the north-west shifts to the Bay of Bengal. It results in the formation of cyclones over the Bay. These cyclones cause havoc on the coasts of Orissa and Andhra Pradesh. 

1. Social Stratification is social in nature: This stratification is based on the social recognition and importance but not on any physical traits. 

2. Social Stratification is Universal: In any human society social stratification exists based on division of labour, profession, income and other social traits. 

3. Social Stratification is ancient: Social stratification exists since the birth of society.

• Social stratification exists in different ways in different regions.
• In ancient Rome, differences existed between – plebians & patricians. In India, social stratification is based on varna system.

• Unemployment. 
• Shortage of food and malnutrition. 
• Burden on civic and social amenities. 
• Low per capital income 
• Slow economic development. 
• Political and social unrest. 
• Low Standard of Living. 
• Poverty. 
• Environmental pollution. 
• Strain on resources.

Large Scale Maps: The Maps drawn on the scale of lcm=lkm or 1:1, 00,000 and 1 inch = 1 mile or 1:63,360 eg. Cadastral maps (Village, Town and City maps).

A land form is any natural formation of rock and dirt, found on the earth. A land form can be as. large as a mountain range or as small as a hill. Land forms are natural features of the landscape, natural physical features of the earth’s surface eg. Valleys, plateaus, Mountains, plains, hills loss plains. The minor land forms include hills, ridges, valleys, basin etc. According to Geo-scientist the land forms are formed by the forces acting from the interior and on the surface of the Earth.

The processes carried out by Endogenic and Exogenic forces are called geomorphic processes. 

Endogenic forces: The internal forces are also known as endogenic forces. These are mainly the land building forces. Diastrophism includes all these processes; that move, elevate or build portions of the earth’s crust.

The internal forces are also known as endogenic forces. 

Exogenic Forces: The external forces are also known as Exogenic forces. These forces are found on the surface of the Earth, Which bring changes through degradation and aggradations process. River, glacier, wind, sea waves are the major sources of external forces.

Earthquake occur due to several causes such as plate movements, volcanic eruption, faulting and folding, landslides, collapse of underground cave roofs, hydrostatic pressure of man made water bodies like reservoirs etc., In India most of the earthquakes that have occurred earlier were due to plat movement.

Map reading means getting the correct visual image of the features shown on a map. 

The Himalayas are also classified into Regional and Longitudinal divisions. They are:

The Kashmir Himalayas The Himachal Himalayas The Kumaun Himalayas The Central or Sikkim Himalayas The Eastern Himalayas.

a. The Kashmir Himalayas: They are spread over in Jammu and Kashmir for about 700sqkm. The important parallel ranges in the Kashmir Himalaya are Karakoram, Ladak, Zaskar and Pirpanjal. They are characterized by high snow covered peaks, largest number of glaciers, deep valleys and High Mountain passes. The north-eastern part of the Kashmir Himalayas is a cold region and it lies between the Grater Himalayas and the Karakorum ranges. A special feature of the Kashmir valley is the Karewas. The important mountain passes are Banihal, zoji-la, Chang-la, Khardung-la etc.

b. The Himachal Himalayas: It is found in Himachal Pradesh and parts of Punjab, comprising of all the three ranges. The beautiful valleys of Kullu, Kangra, Lahul and Spiti known for orchards and scenic beauty are found here. Shipkila, Rohtang, bara- lacha la are the famous mountain passes and Kullu manali, shimla, Dalhousie, Chama etc.

c. The Kumaun Himalayas: This section extends from Sutlej to kali river valleys and has distance of320kms. The pilgrimage centers like Badrinath and Gangothri are located in this section of Himalayas. 

d. The Central or Sikkim Himalayas: This section extends from kali to Tista and has a distance of about 800kms. It is also called as Nepal Himalaya. Mount Everest is located in this 3 sectino of Himalaya. This section is further divided for the study into Sikkim, Darjeeling and Bhutan Himalayas.

e. The Eastern Himalayas: This range extends from Tista to Brahmaputra valley covering the states of Assam and Arunachal Pradesh. The width is about 730 kms Naga and Patkaibhum hills are located in this section. This region is very important for tea cultivation.

The earthquake waves based on their mode of traveling and velocity are broadly classified into three types. They are,

1. Primary (P) waves 

2. Secondary (S)waves 

3. Surface (L) waves

1. Primary (P) waves: These are also known as Push waves or waves of compression. The particles vibrate in the direction of the movement of the wave, similar to a sound wave. They can travel through solid, liquid and gases. The velocity varies from 5.5 to 13 km per second depending on the medium of their travel they are the first to be recorded in the epicenter by the seismograph.

2. Secondary (S) waves: They are recorded on a seismogram after the P) waves. These are also called traverse or shake waves (S). These are distortional waves as the particles vibrate at right angles to the direction of the movement of the waves. The velocity of the secondary waves varies form 3 to 7 kms per second. They can travel through the interior and outer layer of the earth but cannot be transmitted by liquids.

3. Surface waves: These are also described as Long waves (L). The ‘L’ waves travel along the surface of the earth and are recorded after ‘P’ and ‘S’ waves. Their speed is 4 kms. The surface waves are most destructive as they vibrate much.

Correct answer is 40

Organic compound \(\xrightarrow{AgNO_ 3}\) AgCl

(Containing chlorine) 0.4 gram

0.25 gram

Mole of AgCl = (0.4/143.5)

W_Cl = (0.4/143.5) x 35.5

% of Cl = [0.4/143.5 x 35.5] x 100/0.25 = 39.58

Mineral is a natural inorganic substance which has certain chemical and physical properties. The scientific study of minerals is called Mineralogy. Minerals are used by man for various human activities. Understanding them minerals their types and uses is very important as natural resources of the earth.

Types: Minerals are classified into different types on the basis of nature, texture, and sues. Important among them are,

1. Metallic Minerals: These minerals are not in metallic form and they do not contain metal. A few non-metallic minerals are Mica, Asbestos, Sulphur, lead, Zinc, Phosphate etc. 

2. Non-Metallic Minerals: These minerals are not in metallic form and they do not contain metal. A few non-metallic minerals are Mica, Asbestos, Sulphur, Lead, Zinc, Phosphate etc.

Minerals are also classified into other types.

Ferrous minerals which contain Iron e.g. Iron Ore. Non-ferrous minerals – these minerals do not contain ferrous e.g. Bauxite, Mica. – A few minerals are used for making decorative, commercial and precious ornaments are called Precious minerals. E.g. Platinum, Diamond, Gold and Silver. Some minerals are use for the generation of energy. They are Nuclear or atomic minerals e.g. Uranium, Thorium etc.

Forests are the one of the important natural resources. They provide various benefits to mankind and environment.

The important benefits are:

1. Forests supply fresh air, food and fodder. 

2. Forests are the rain bearers, help in causing good rainfall. 

3. They control soil erosion and desertification. 

4. Forest provides various products like bamboo, timber, resin, lac, gum cane, fuel, wood etc.

5. They provide medicinal trees and plants used in ayurvedic medicines Eg.Neem tree. Basil, Brahmi etc. 

6. They provide shelter to various birds and animals. 

7. They absorb much of the rainwater and control floods and safeguards against drought. 

8. They act as wind breakers and protect the agricultural crops. 

9. The forest soils are rich in humus and thereby maintain the fertility of the soil. 

10. They provide raw materials to paper, match box, plywood and sports articles industries and they provide pastures for grazing animals.

Title, Scale, Direction are essential features of a Map.

An earthquake is a sudden release of energy accumulated in rocks causing the ground to tremble or shake. . The main causes of earthquake are natural and man – made factors.

• Tectonic forces 
• Volcanic activity 
• Landslides and Landslips 
• Collapse of underground cave roofs

1. Physical Geography. 

The field of physical geography is wide as it includes the study of the entire surface of the earth and also its physical and biological process as well as their morphology. Modern geography has witnessed the development of many branches and some of them even grown into separate disciplines.

Some of the important branches of physical geography are as follows:

• Geomorphology: It is a systematic study of l and forms, such as mountains, plateaus, plains, valleys, etc. 
• Climatology: Climatology encompasses the study of structure of atmosphere and elements of climates and climatic types and regions. 
• Meteorology: The scientific study of atmosphere condition is called meteorology. 
• Pedology: It is the scientific study of soil formation, structure, texture, chemical composition and their influence on plant growth.
• Hydrology: Hydrology studies the realm of water over the surface of the earth including oceans, lakes, rivers and other water bodies and its effect on different life. 
• Seismology: It is the study of Earthquakes, their effects and distribution. 
• Astronomical Geography: It is the study of heavenly bodies of the space like planets, satellites, stars etc in relation to the earth. 
• Volcanology: It is the scientific study of tectonic process of volcanoes. 
• Astronomical geography: It is the study of heavenly bodies of the space like planets, satellites, stars etc in relation to the earth. 
• Bio-geography: It is the systematic study of the distribution of plants and animals. 
• Hydrology: The study of water on the earth’s land is known as hydrology. 
• Oceanography: The study of waves, tides and currents and the other characteristics of oceans, known as oceanography. 

2. Human geography: It deals with man and his activities particularly cultural environment factors on man made factors, Important among them are culture, Society, agriculture, mining, industry, transport forming trade population etc. Some of the important grander of Human geography are as fallows:

• Political geography: It deals with spatial unit, people distribution, political behavior, political divisions etc. 
• Economic geography: It refers to basic attributes of the economy such as production, distribution exchange of goods and consumption. It deals with the spatial aspects of production, distribution and consumption and also helps on understanding the most proper location for establishing different human activities.
• Commercial Geography: It deals with the spatial distribution of trade and commercial practices etc. 
• Population Geography: It helps to understand the distribution, growth density, migration and various other components of population.

Rotation of the Earth causes various effects. They are:

a. Day and night caused by the rotation of the earth on its axis. This is because parts of the earth which face the sun have day and the parts which do not face the sun have night. This happen with precision and progression and not suddenly – The time when the sun beings to cast its light in the sky is known as dawn. At noon. The sun is overhead. At dusk, it is twilight and the sun is seen disappearing in the sky. At night, it is completely dark.

b. The duration of the day and night is not equal at all places on the earth because of the inclined axis. The length of days varies with respect to the seasons as well as latitude 

c. The sun, the moon and the stars seem to move from east to west. This is because the earth spins from west to east. This effect is similar to what one experiences while looking at trees from a moving train.

d. The speed of rotation has created a centrifugal force resulting in a bulge in the middle portion of the earth and flattened top at the poles. 

e. The earth’s rotation affects the movement of water in the oceans. The tides are deflected because of the rotation of the earth.

f. Rotation causes difference in time over various places on the earth. 

g. The Earth acts as huge magnet: The one end of the needle of the compass always points towards the north magnetic pole. That means, the earth acts as a magnet. The rotation . of the earth causes the earth to act as a magnet.

h. Rotation of the Earth influences the movement of ocean water, particularly ocean currents. 

i. The rise and fall in the sea level is called tides. Rotation of the Earth causes the lacing of water bodies to the Moon. The gravitational attraction of the Moon and position of the water bodies cause tides. This is a regular phenomenon due to Earth’s rotation.

Disintegration and Decomposition of rocks by chemical processes is called “Chemical weathering”.

In this process secondary or new minerals are developed from the original minerals of the rocks. The rain water and atmospheric gases are the main agents of chemical weathering. It is very common in humid regions.

There are four types of chemical weathering process. They are:

a. Oxidation: The rain water with oxygen reacts on rocks containing iron and produce oxides. This chemical reaction is known as “oxidation”. The common process of rusting of iron is an example of oxidation. . 

b. Carbonation: The rain water with carbon-di-oxide becomes a weak carbonic acid and it reacts with calcium carbonate or limestone to form calcium bicarbonate, which dissolves easily. This process is called “Carbonation”. It is very active in limestone regions.

c. Hydration: The rock minerals take up water the increased volume creates physical stress within the rock. As a result certain minerals like feldspar and gypsum are reduced into powder. This process is called “Hydration”.

d. Solution: The rain water is able to dissolve some of the soluble minerals, such as rock- salt, gypsum, potash. This process is called “Solution”. 

Rotation of the Earth causes various effects. They are:

a. Day and night caused by the rotation of the earth on its axis. This is because parts of the earth which face the sun have day and the parts which do not face the sun have night. This happen with precision and progression and not suddenly – The time when the sun beings to cast its light in the sky is known as dawn. At noon. The sun is overhead. At dusk, it is twilight and the sun is seen disappearing in the sky. At night, it is completely dark.

b. The duration of the day and night is not equal at all places on the earth because of the inclined axis. The length of days varies with respect to the seasons as well as latitude.

c. The sun, the moon and the stars seem to move from east to west. This is because the earth spins from west to east. This effect is similar to what one experiences while looking at trees from a moving train.

d. The speed of rotation has created a centrifugal force resulting in a bulge in the middle portion of the earth and flattened top at the poles.

e. The earth’s rotation affects the movement of water in the oceans. The tides are deflected because of the rotation of the earth.

f. Rotation causes difference in time over various places on the earth.

g. The Earth acts as huge magnet: The one end of the needle of the compass always points towards the north magnetic pole. That means, the earth acts as a magnet. The rotation . of the earth causes the earth to act as a magnet. 

h. Rotation of the Earth influences the movement of ocean water, particularly ocean currents.

i. The rise and fall in the sea level is called tides. Rotation of the Earth causes the lacing of water bodies to the Moon. The gravitational attraction of the Moon and position of the water bodies cause tides. This is a regular phenomenon due to Earth’s rotation.