Class XI – Geography Paper – 4

Ans. (B) Both (A) and (R) are true and (R) is the correct explanation of (A).

Explanation: The reason correctly explains why geography is concerned with these three sets of questions. Geography indeed involves identifying, analysing the distribution of various features on Earth’s surface, and understanding how these features and their spatial relationships influence various processes and phenomena.

Ans. Option (B)

Explanation:

• Geomorphology is the branch of geography that focuses on the study of landforms, their origins, and how they evolve over time.

• Climatology is the study of the Earth’s climate, including the structure and behaviour of the atmosphere, weather patterns, and long-term climate trends

• Hydrology is the study of water in the Earth’s atmosphere, on its surface, and underground. It includes the study of water distribution, movement, and properties.

• Soil Geography is the branch of geography that focuses on the study of soil, including its formation processes, types, distribution, and properties.

Ans. (A) Plant

Explanation: Plant Geography is the part of geography that studies the spatial pattern of natural vegetation in their habitat.

Ans. (A) Both statements are true

Explanation: Nebular hypothesis states the planet formation in different stages; the first stage states that Self-gravity contracts a gas cloud and conservation of angular momentum pulls the cloud into a disk. In the second stage, the Disk begins to rotate then Central mass forms and centrifugal force balances gravitational forces and forms a ring and finally ring forms a planet.

Ans. Option (C)

Explanation: The water cycle discusses the different stages of water including, evaporation, transition, condensation and precipitation.

Ans. (A) Eons

Explanation: Eons are the longest divisions of time and encompass billions of years. For example, the Phanerozoic Eon covers the last 541 million years and includes all of Earth’s complex life forms.

Ans. (C) temperature

Explanation: The earth as a whole does not accumulate or lose heat. It maintains its temperature.

Ans. (A) mercury barometer

Explanation: A mercury barometer is a barometer with a column of mercury whose height varies according to atmospheric pressure. It is used in forecasting the weather.

Ans. (A) High pressure develops over North-western India due to low temperatures.

Explanation: Northern hemisphere experience winter during this time as solar energy is less received. As a result, high pressure prevails in the Northwestern part of India.

Ans. (A) Only statement I is correct

Explanation: These forests have a mixture of evergreen and moist deciduous trees but are found in less rainy parts of tropical evergreen forests.

Ans. (D) i, iii, ii, iv

Explanation:

(i) Weather conditions in India are influenced by the distribution of pressure in Central and Western Asia.

(iii) A high-pressure center develops in the region north of the Himalayas during winter.

(ii) Continental winds from Central Asia come in contact with trade winds over north-western India.

(iv) Tropical cyclones originate over the Bay of Bengal and the Indian Ocean, which is less relevant to the mechanism of winter weather in India.

Ans. (C) to protect tigers from illegal hunting

Explanation: The aim of Project Tiger is to safeguard the population of tigers.

Ans. (C) The Ganga

Explanation: The Ganga has the largest river basin in India, flowing through multiple states and holding immense cultural and religious significance.

Ans. (D) Deva Prayag

Explanation: The place of confluence of the Alaknanda and Bhagirathi rivers is Deva Prayag, located in Uttarakhand, India.

Ans. (B) 2011

Explanation: According to the above-given graph, in 2011 the total number of occurred earthquakes are 2481 which is the highest of all years.

Ans. (C) 2002

Explanation: According to the above-given graph, in 2002 the total number of occurred earthquakes are 1341 which is the lowest of all years.

Ans. (A) 1844

Explanation: According to the above-given graph, in 2005 the total number of occurred earthquakes are 1844.

Ans. Erosion is largely responsible for continuous changes that the earth’s surface is undergoing.

Ans. Kinetic energy controls the denudational processes.

Ans. Karst topography forms only when rocks are permeable and soluble and water is available.

Ans. Northern part of India, majorly in the Himalayas.

Ans. Uttar Pradesh is dominated by Tropical Deciduous Forests

Ans. Semi-Evergreen forests are majorly seen in the western ghats of India.

Ans. The planet Earth initially was a barren, rocky and hot object with a thin atmosphere of hydrogen and helium. This is far from the present-day picture of the Earth. It is concluded that in the initial stage, the earth was in liquid form. A number of events that took place over millions of years have turned the earth into what it looks like today, i.e., a beautiful planet with ample amount of water and a conductive atmosphere favouring the existence of life.

Ans. The gases which initially formed the earth’s atmosphere were namely hydrogen and helium. The early atmosphere, with hydrogen and helium, is supposed to have been stripped off as a result of the solar winds. This happened not only in the case of the Earth but also in all the terrestrial planets, which were supposed to have lost their primordial atmosphere through the impact of solar winds. During the cooling of the earth, gases and water vapour were released from the interior solid earth. This started the evolution of the present atmosphere. The early atmosphere largely contained water vapour, nitrogen, carbon dioxide, methane, ammonia and very little free oxygen.

Ans. Geomorphic agents are different from geomorphic processes in the following ways:

Geomorphic agents: An agent is a mobile medium that removes, transports and deposits earth materials. Running water, groundwater, glaciers, wind, waves and currents, etc., can be called geomorphic agents.

Geomorphic processes: The endogenic and exogenic forces causing physical stresses and chemical actions on earth’s material and bringing about changes in the configuration of the surface of the earth are known as geomorphic processes.

Ans. A Biosphere Reserve is a unique representative ecosystem of terrestrial and coastal areas which are internationally recognised within the framework of UNESCO’s Man and Biosphere (MAB) Programme. The main objectives of biosphere reserves are:

(i) Conservation of the biodiversity and ecosystem.

(ii) Association of environment and development.

(iii) International network for research and monitoring.

Ans. The main objective of the scheme is to ensure the maintenance of the viable population of tigers in India for scientific, aesthetic, cultural and ecological values and to preserve areas of biological importance as a natural heritage for the benefit, education and enjoyment of the people.

Initially, Project Tiger was launched in nine tiger reserves, covering an area area of 16,339 sq. km, which has now increased to 44 tiger reserves, encompassing 36,988.28sq. km of tiger habitats distributed in 17 states. The tiger population in the country has registered an increase from 1,411 in 2006 to 1,706 in 2010.

Ans. To the northwest of the Aravali hills lies the Great Indian desert. It is a land of undulating topography dotted with longitudinal dunes and barchans. This region receives low rainfall below 150 mm per year; hence, it has arid climate with low vegetation cover. It is because of these characteristic features that this is also known as Marusthali.

The vegetation common in the region are Cacti, Kher, Kikar, Babool, Aclacia, Rhododendrons, etc. During the rainy season, some streams appear which disappear in summer. Luni is an important river in the region.

Some of the well-pronounced desert land features present here are mushroom rocks, shifting dunes and oasis. On the basis of the orientation, the desert can be divided into two parts: the northern part is sloping towards Sindh and the southern towards the Rann of Kachchh. Most of the rivers in this region are ephemeral.

Ans. Warming and cooling of the Pacific Ocean is most important in terms of general atmospheric circulation. The warm water of the central Pacific Ocean slowly drifts towards the South American coast and replaces the cool Peruvian current. Such appearance of warm water off the coast of Peru is known as the El Nino. The El Nino event is closely associated with the pressure changes in the Central Pacific and Australia. This change in pressure conditions over the Pacific is known as the Southern oscillation. The combined phenomenon of southern oscillation and El Nino is known as ENSO. In the years when the ENSO is strong, large-scale variations in weather occur over the world. The arid west coast of South America receives heavy rainfall, drought occurs in Australia and sometimes in India and floods in China. This phenomenon is closely monitored and is used for long-range forecasting in major parts of the world.

Ans. The impact of currents on temperature varies depending on whether currents are warm or cold.

(i) Cold currents: Cold currents bring cold water into warm water areas. These currents are usually found on the west coast of the continents in the low and middle latitudes (true in both hemispheres) and on the east coast in the higher latitudes in the Northern Hemisphere.

(ii) Warm currents: Warm currents bring warm water into cold water areas and are usually observed on the east coast of continents in the low and middle latitudes (true in both hemispheres). In the Northern Hemisphere, they are found on the west coasts of continents in high latitudes. In North West Europe, warm currents exist. They increase the temperature in coastal areas of NW Europe.

Ans. The size of India has endowed her with great physical diversity. Thus, you may appreciate the presence of lofty mountains in the north; large rivers such as Ganga, Brahmaputra, Mahanadi, Krishna, Godavari and Kaveri; green forested hills in the North East and South India; and the vast sandy expanse of Marusthali. You may further appreciate that bounded by the Himalayas in the north, the Hindukush and Sulaiman range in the northwest, Purvachal hills in the North-East and by the large expanse of the Indian Ocean in the south, it forms a great geographic entity known as the Indian subcontinent. It includes the countries — Pakistan, Nepal, Bhutan, Bangladesh and India. The Himalayas, together with other ranges, have acted as a formidable physical barrier in the past. Except for a few mountain passes such as the Khyber, the Bolan, the Shipkila, the Nathula, the Bomdila, etc. it was difficult to cross it. It has contributed towards the evolution of a unique regional identity of the Indian subcontinent. The peninsular part of India extends towards the Indian Ocean. This has provided the country with a coastline of 6,100 km in the mainland and 7,517 km in the entire geographical coast of the mainland plus the island groups Andaman and Nicobar located in the Bay of Bengal and the Lakshadweep in the Arabian Sea. Thus India, as a country, is a physically diverse land providing the occurrence of varied resources.

Ans. There are several warm ocean currents that move warm water away from the equator. These currents of water have warm air above the water. The warm air raises the temperature of the land it touches These areas enjoy a much warmer climate than other places at the same latitude. Areas such as England would be much colder without the warm Gulf Stream. Warm ocean currents flow on the eastern side of the continent. They only reach the western side in high-latitude areas. Another characteristic is that they flow away from the equator. Warm currents have higher temperatures, so they are less dense than cold water. Usually, warm water has a higher salinity, but it remains less dense than cold water, so cold water is heavier and flows under warm water. The water is warmed on the surface, so warm currents flow across the surface of the ocean. As the warm current cools down, it drops down and becomes a cold water current.

Ans. Depending upon the variations in the climate and the soil, the vegetation of India changes from one region to another.

(i) Tropical Evergreen and Semi Evergreen Forests: These forests are found in the western slope of the Western Ghats, hills of the northeastern region and the Andaman and Nicobar Islands. They are found in warm and humid areas with an annual precipitation of over 200 cm and mean annual temperature above 22°C. The semi evergreen forests are found in the less rainy parts of these regions. Such forests have a mixture of evergreen and moist deciduous trees.

(ii) Tropical Deciduous Forests: These are the most widespread forests in India. They are also called the monsoon forests. They spread over regions that receive rainfall between 70-200 cm. On the basis of the availability of water, these forests are further divided into moist and dry deciduous. The moist deciduous forests are more pronounced in the regions which record rainfall between 100-200 cm. Dry deciduous forest covers vast areas of the country, where rainfall ranges between 70 -100 cm. On the wetter margins, it has a transition to the moist deciduous, while on the drier margins to thorn forests. As the dry season begins, the trees shed their leaves completely and the forest appears like a vast grassland with naked trees all around.

(iii) Tropical thorn forests: They occur in the areas which receive rainfall less than 50 cm. These consist of a variety of grasses and shrubs. It includes semi-arid areas of south west Punjab, Haryana, Rajasthan, Gujarat.

(iv) Montane Forests: In mountainous areas, the decrease in temperature with increasing altitude leads to a corresponding change in natural vegetation. Mountain forests can be classified into two types, the northern mountain forests and the southern mountain forests. The Himalayan ranges show a succession of vegetation from the tropical to the tundra, which change in with the altitude. Deciduous forests are found in the foothills of the Himalayas. It is succeeded by the wet temperate type of forests between an altitude of 1,000-2,000 m. The southern mountain forests include the forests found in three distinct areas of Peninsular India viz; the Western Ghats, the Vindhyas and the Nilgiris. As they are closer to the tropics and only 1,500 m above the sea level, vegetation is temperate in the higher regions and subtropical on the lower regions of the Western Ghats, especially in Kerala, Tamil Nadu and Karnataka.

(v) Littoral and Swamp Forests: India has a rich variety of wetland habitats. About 70 per cent of this comprises areas under paddy cultivation. The total area of wetland is 3.9 million hectares. Two sites — Chilika Lake (Odisha) and Keoladeo National Park (Bharatpur) are protected as water-fowl habitats under the Convention of Wetlands of International Importance (Ramsar Convention)

Ans. (i) While in the summer the mercury occasionally touches 55°C in the western Rajasthan, it drops down to as low as minus 45°C in winter around Leh. Churu in Rajasthan may record a temperature of 50°C or more on a June day while the mercury hardly touches 19°C in Tawang (Arunachal Pradesh) on the same day. On a December night, temperature in Drass (Jammu and Kashmir) may drop down to minus 45°C, while Thiruvananthapuram or Chennai on the same night records 20°C or 22°C. These examples confirm that there are seasonal variations in temperature from place to place and from region to region in India. While snowfall occurs in the Himalayas, it only rains over the rest of the country. Similarly, variations are noticeable not only in the type of precipitation but also in its amount. While Cherrapunji and Mawsynram in the Khasi Hills of Meghalaya receive rainfall over 1,080 cm in a year, Jaisalmer in Rajasthan rarely gets more than 9 cm of rainfall during the same period. The Ganga delta and the coastal plains of Odisha are hit by strong rain-bearing storms almost every third or fifth day in July and August while the Coromandal Coast, a thousand km to the south, goes generally dry during these months. Most parts of the country get rainfall during June-September, but on the coastal areas of Tamil Nadu, it rains in the beginning of the winter season.

(ii) The difference between the maximum average temperature and minimum average temperature of a place over twelve months is known as annual range of temperature. Example: The maximum average temperature at Jodhpur is 33.9°C and the minimum average temperature is 14.9°C. Hence, the annual range of temperature at Jodhpur is 19°C (33.9°C -14.9°C).

Ans. Alluvial fans are formed when streams flowing from higher levels break into foot slope plains of low gradient. Normally very coarse load is carried by streams glowing over mountain slopes. This load becomes too heavy for the streams to be carried over gentler gradients and gets dumped and spread as a broad low to high cone-shaped deposit called an alluvial fan. Usually, the streams which flow over fans are not confined to their original channels for long and shift their position across the fan forming many channels called distributaries. Alluvial fans in humid areas show normally low cones with gentle slopes forming as a low cone.

Delta is like alluvial fans but develop at a different location. The load carried by the rivers is dumped and spread into the sea. If this load is not carried far away into the sea or distributed along the coast, it spreads and accumulates. Such areas over flood plains build up by abandoned or cut-off channels contain coarse deposits.

The flood deposits of spilt waters carry relatively finer materials like silt and clay. The flood plains in a delta are called delta plains. Floodplain is a major landform of river deposition.

Large-sized materials are deposited first when the stream channel breaks into a gentle slope. Thus, normally, fine-sized materials like sand, silt and clay are carried by relatively slow-moving waters in gentler channels usually found in the plains and deposited over the bed and when the waters spill over the banks during flooding above the bed. These river valley plains have a fertile alluvial soil cover which supports a variety of crops like wheat, rice, sugarcane and jute, and hence, supports a large population.

Ans. Factors that determine the volume of water in a river are:

(i) Size of the drainage basin: A drainage basin in an area drained by one main river and its tributaries determines the volume of water in a river. If the drainage basin is large, the volume of water in the river will be more. On the other hand, if the drainage basin is small, volume of water in the river will be less because there is less surface area for the rain to fall on.

(ii) Vegetation: Leaves of trees intercept rainwater and allow more water to sweep into the ground in groundwater. As a result, the amount of surface runoff reduces. Therefore, the volume of water in the river is less where vegetation is dense. Spare vegetation prevents rainwater from getting trapped in the leaves and branches, thereby allowing more water to flow through as surface runoff. So in areas with less vegetation volume of water is more.

(iii) Permeability of rocks: In areas with permeable or porous rocks, much of the rainwater sweeps through the pores in the rocks into the ground. In such areas, surface runoff is less and water flowing into the river channel will also be less.

(iv) Climate: In areas with hot and wet climates such as equatorial areas, the volume of water in rivers will be high. However, the amount of water will be less in areas with dry climates receiving less rainfall. In areas with prominent wet or dry seasons, the volume of water in the river will vary according to the amount of rainfall received.

(v) Riverbed gradient: The gradient of a river refers to how steep its slope is, this also has a significant effect on the velocity of a river. When a river flows down a steep slope, the gravitational force that pulls the water downward is stronger than it would be on water flowing down a gentle slope.

Ans. Himachal Pradesh

Ans. New Mangalore

Ans. Hyderabad

Ans. Raniganj

Ans. Assam

Ans. Bihar

Ans. Maharashtra

Ans.