Lesson 5 Minerals and Energy Resources Class 10th Subject –Social Science (Geography) Book- Contemporary India ( For English medium Students))

                                                                     

Lesson 5

Minerals and Energy Resources

Class 10^th

Subject –Social Science (Geography)

Book- Contemporary India

Question: What is a mineral?

According to the Geologists “homogenous, naturally occurring substance with a definable internal structure” is known as mineral.

Minerals are found in varied forms in nature, ranging from the hardest diamond to the softest talc.

Question: Write about the Importance of Minerals.

OR

Question: Minerals are an indispensable part of our lives. Explain.

Answer: Importance of Minerals is given below.

         (i)         Minerals are an indispensable part of our lives.

        (ii)        Almost everything we use, from a tiny pin to a towering building or a big ship, all are made from minerals.

       (iii)       The railway lines and the tarmac (paving) of the roads, our implements and machinery too are made from minerals.

       (iv)       Cars, buses, trains, aeroplanes are manufactured from minerals and run on power resources derived from the earth.

        (v)        Even the food that we eat contains minerals.

       (vi)       In all stages of development, human beings have used minerals for their livelihood, decoration, festivities, religious and ceremonial rites.

Question: What minerals do your toothpastes have cleaning quality?

Answer: Abrasive minerals like Silica, Limestone, Aluminium Oxide and various Phosphate minerals do the cleaning quality.

Question: From which mineral is fluoride obtained and what is it use?

Answer: Fluoride is obtained from a mineral fluorite. It is used to reduce cavities in teeth.

Question: Why does tooth powder provide lustre to our teeth?

Answer: Because mica is present in those tooth power or tooth paste.

Question: By which material toothpaste is made white and from which minerals it is obtained?

Answer: Most toothpaste is made white with titanium oxide; it comes from minerals called rutile, ilmenite and anatase.

Question:  What is the tooth brush and toothpaste tube made of?

Answer: The tooth brush and tube containing the paste are made of plastics from petroleum.

Question: ‘Rocks are combinations of minerals’. Explain.

Answer: Rocks are combinations of homogenous substances called minerals.

Some rocks, for instance limestone, consist of a single mineral only,

Majority of the rock consist of several minerals in varying proportions.

Question: Which rock consists of single mineral only?

OR

Name the rock which is made of one mineral.

Answer:  limestone, consist of a single mineral only

Question:  How many minerals are identified yet so far?

Answer:  Approximate 2000 minerals have been identified till now.

Question:  Why are minerals so varied?

OR

Question: What are the properties by which is used by Geologists to classify the minerals.

Answer:  A particular mineral that will be formed from a certain combination of elements depends upon the physical and chemical conditions under which the material forms.

This results in a wide range of colours, hardness, crystal forms, lustre and density that particular mineral possesses. Geologists use these properties to classify the minerals.

Question: In what form are minerals generally found?

Answer: Minerals are usually found in the form of “ores”

Question: Give definition of ore. 

Answer: The term ore is used to describe an accumulation of any mineral mixed with other elements.

Question: How do minerals occurs in igneous and metamorphic rocks?

OR

Question: How are minerals formed in igneous and metamorphic rocks?

Answer:

In igneous and metamorphic rocks minerals may occur in the cracks, crevices, faults or joints.

The smaller occurrences are called veins and the larger are called lodes.

In most cases, they are formed when minerals in liquid/ molten and gaseous forms are forced upward through cavities towards the earth’s surface.

They cool and solidify as they rise.

Major metallic minerals like tin, copper, zinc and lead etc. are obtained from veins and lodes.

Question: How do minerals occurs in sedimentary rocks?

Answer:  In sedimentary rocks a number of minerals occur in beds or layers.

They have been formed as a result of deposition, accumulation and concentration in horizontal strata.

 Coal and some forms of iron ore have been concentrated as a result of long periods under great heat and pressure.

Another group of sedimentary minerals include gypsum, potash salt and sodium salt. These are formed as a result of evaporation especially in arid regions.

Question: How we get minerals from the decomposition of surface rocks, and the removal of soluble constituents.

Answer: Another mode of formation involves the decomposition of surface rocks, and the removal of soluble constituents, leaving a residual mass of weathered material containing ores. Bauxite is formed this way.

Question: How are minerals formed in alluvial deposits? Name any four minerals formed in alluvial deposits.

Answer: Certain minerals may occur as alluvial deposits in sands of valley floors and the base of hills. These deposits are called ‘placer deposits’ and generally contain minerals, which are not corroded by water.

Gold, silver, tin and platinum are most important among such minerals.

Question: The ocean waters contain vast quantities of minerals explain it.

OR

 Question: Minerals found in ocean waters mostly are not of economic significance. Give one reason. Name the minerals derived from ocean waters.

Answer: The ocean waters contain vast quantities of minerals; most of these are too widely diffused so they are not of economic significance.

Minerals derived from ocean waters

Common salt, magnesium and bromine are largely derived from ocean waters.

The ocean beds are rich in manganese nodules.

 

Question: In which areas in India mining are owned by individuals or communities.

Answer: Most of the minerals in India are nationalized and their extraction is possible only after obtaining due permission from the government.

But in most of the tribal areas of the north-east India, minerals are owned by individuals or communities.

In Meghalaya, there are large deposits of coal, iron ore, limestone and dolomite etc.

Question: What is “Rat-Hole Mining”? Explain with example.

Answer: When mining is done in the form of a long narrow tunnel, known as ‘Rat Hole Mining’.  Coal mining in Jowai and Cherapunjee is done by family member. It is a type of ‘Rat Hole Mining’.

The National Green Tribunal has declared such activities illegal and recommended that these should be stopped forthwith.

Question: ‘India is fortunate to have fairly rich and varied mineral resources’. Give reasons.

OR

Question: ‘Minerals in India are unevenly distributed’. Explain it.

Answer: India is fortunate to have fairly rich and varied mineral resources.

However, these are unevenly distributed.

Peninsular rocks contain most of the reserves of coal, metallic minerals, mica and many other non-metallic minerals.

Sedimentary rocks on the western and eastern flanks of the peninsula, in Gujarat and Assam have most of the petroleum deposits.

Rajasthan with the rock systems of the peninsula has reserves of many non-ferrous minerals. The vast alluvial plains of north India are almost devoid of economic minerals.

Question: How does a deposit or a reserve become a mine?

Answer: The concentration of mineral in the ore, the ease of extraction and closeness to the market play an important role in affecting the economic viability of a reserve.

To meet the demand, a choice has to be made between a numbers of possible options. When this is done a mineral ‘deposit’ or ‘reserve’ turns into a mine.

Question: What are ferrous metallic minerals? What is the importance of ferrous metallic minerals?

Answer: Those minerals which have iron content are known as Ferrous Minerals.

Iron Ore, Manganese, nickel and cobalt are the major Ferrous Minerals.

Ferrous minerals account for about three fourths of the total value of the production of metallic minerals. They provide a strong base for the development of metallurgical industries.

India exports substantial quantities of ferrous minerals after meeting her internal demands.

Question: What are non- ferrous metallic minerals?  Give example.

Answer: Minerals which do not have iron contents are called non- ferrous metallic minerals.

Copper, led, tin and Bauxite etc. are example of non- ferrous metallic minerals.

In India reserves and production of non-ferrous minerals is not very satisfactory.

Question: Write the names of precious metallic minerals.

Answer: Gold, silver and platinum are the precious metallic minerals

India is deficient in non- ferrous metallic minerals.

Question: Describe various types of Iron Ore found in India. Also write the names of major states that produce iron ore

Answer: Iron ore is the basic mineral and the backbone of industrial development. India is endowed with fairly abundant resources of iron ore.  

Type of iron ore found in India

India is rich in good quality iron ores. Two types of iron ore are mainly found in India.

         (i)         Magnetite is the finest iron ore with a very high content of iron up to 70 per cent. It has excellent magnetic qualities, especially valuable in the electrical industry.

        (ii)        Hematite ore is the most important industrial iron ore in terms of the quantity used. It has slightly lower iron content than magnetite that is 50-60 per cent.

Production of iron ore in India

In 2018–19 almost entire production of iron ore (97%) accrued from Odisha, Chhattisgarh, Karnataka and Jharkhand. The remaining production (3%) was from other states.

Question: What is the meaning of Kudre and Bailadila?

Answer:

         (i)         Kudre in Kannada means horse. The highest peak in the western ghats of Karnataka resembles the face of a horse.

        (ii)        The Bailadila hills look like the hump of an ox, and hence its name.

Question: Explain the distribution of iron ore in India

OR

Question: Name the iron –ore belts in India. List the features of these belts.

The major iron-ore belts in India are:

Odisha-Jharkhand belt:

In Odisha high grade hematite ore is found in Badampahar mines in the Mayurbhanj and Kendujhar districts.

In the adjoining Singbhum district of Jharkhand haematite iron ore is mined in Gua and Noamundi.

Durg-Bastar-Chandrapur belt  (features of Bailadila hills mines of iron ore)

 

This belt lies in Chhattisgarh and Maharashtra.

Very high grade hematites are found in the famous Bailadila range of hills in the Bastar district of Chhattisgarh. The range of hills comprises of 14 deposits of super high grade hematite iron ore.

It has the best physical properties needed for steel making.

 Iron ore from these mines is exported to Japan and South Korea via Vishakhapatnam port.

Ballari-Chitradurga-Chikkamagaluru-Tumakuru belt (features of Kudremukh mines of iron ore)

This belt in Karnataka has large reserves of iron ore.

The Kudremukh mines located in the Western Ghats of Karnataka are a 100 per cent export unit.

Kudremukh deposits are known to be one of the largest in the world.

The ore is transported as slurry through a pipeline to a port near Mangaluru.

Maharashtra-Goa belt

It  includes the state of Goa and Ratnagiri district of Maharashtra.

Though, the ores are not of very high quality, yet they are efficiently exploited.

Iron ore is exported through Marmagao port.

Question: What are the uses of Manganese? Explain the distribution of Manganese ore in India.

Answer:

Uses of Manganese

Manganese is mainly used in the manufacturing of steel and ferro-manganese alloy.

Nearly 10 kg of manganese is required to manufacture one tonne of steel.

It is also used in manufacturing bleaching powder, insecticides and paints.

 Distribution of Manganese ore in India

Production of Manganese showing state-wise share in per cent, 2018–19

Madhya Pradesh 33%, Odisha 16%, Karnataka 12%, Andhra Pradesh 10%,   Others 2%, Maharashtra 27%

Question: Write the names of Non-Ferrous Minerals? What is the importance of these minerals?

Answer: Non-Ferrous Minerals include copper, bauxite, lead, zinc and gold.

These minerals play a vital role in a number of metallurgical, engineering and electrical industries.

Question: Explain the uses and distribution of Copper in India.

OR

Question: What are the uses of copper? Write the names of leading copper producing states with their mines in India. 

Answer:

Uses of copper:

Being malleable, ductile and a good conductor, copper is mainly used in electrical cables, electronics and chemical industries.

Production and distribution of copper in India :

India is critically deficient in the reserve and production of copper.

The Balaghat mines in Madhya Pradesh, Khetri mines in Rajasthan and Singhbhum district of Jharkhand are leading producers of copper.

Question: what is bauxite? How is it formed? Write about the qualities of Aluminium? 

                                                                        OR

Question: How aluminium is obtained? What are the the qualities of Aluminium?

Answer: Bauxite is a clay-like substance. From bauxite alumina and later aluminium is obtained. Bauxite deposits are formed by the decomposition of a wide variety of rocks rich in aluminium silicates.

Qualities of Aluminium

Aluminium is an important metal because it combines the strength of metals such as iron, with extreme lightness and also with good conductivity and great malleability.

Question: Write the distribution and production of bauxite in India.

Answer:

         (i)         In India bauxite deposits are mainly found in the Amarkantak plateau, Maikal hills and the plateau region of Bilaspur-Katni.

        (ii)        Production of Bauxite showing state-wise share in per cent in 2018–19 are given below.

       (iii)       Odisha is the largest bauxite producing state in India with 65% of total bauxite production. Koraput is the important deposits of bauxite.

       (iv)       Chhattisgarh produce 6% bauxite. Bilaspur is the important bauxite producing region of this state.  

        (v)        Jharkhand, Gujarat, Maharashtra, Madhya Pradesh are other major bauxite producing states.  

Question: Which type of mineral is Mica? What are the characteristics of Mica? Explain the distribution of Mica in India.

Answer: Non-Metallic Minerals.

Characteristics of Mica

         (i)         Mica is a mineral made up of a series of plates or leaves.

        (ii)        It splits easily into thin sheets.

       (iii)       These sheets can be so thin that a thousand can be layered into a mica sheet of a few centimeters high.

       (iv)       Mica can be clear, black, green, red yellow or brown.

 Question: Why mica is one of the most indispensable minerals used in electric and electronic industries.

Answer: Due to its excellent di-electric strength, low power loss factor, insulating properties and resistance to high voltage, mica is one of the most indispensable minerals used in electric and electronic industries.

Question: Write about the Distribution of mica in India.  

Answer: Distribution of mica in India is discussed below

         (i)         Mica deposits are found in the northern edge of the Chota Nagpur plateau.

        (ii)        Koderma Gaya – Hazaribagh belt of Jharkhand is the leading producer.

       (iii)       In Rajasthan, the major mica producing area is around Ajmer.

       (iv)       Nellore mica belt of Andhra Pradesh is also an important producer in the country.

 

Question: In which type of rock is limestone found?

Answer: Limestone is found in association with rocks composed of calcium carbonates or calcium and magnesium carbonates.

It is found in sedimentary rocks of most geological formations.

Question: what are the uses of lime stone?

Answer: Limestone is the basic raw material for the cement industry.

It is essential for smelting iron ore in the blast furnace.

Question:  Write the names of the major states where limestone found? 

Answer:  Rajasthan, Andhra Pradesh, Madhya Pradesh, Gujarat, Tamil Nadu, Telangana, Karnataka, Chhattisgarh and Maharashtra are the major states where limestone found

Question: Why Mining is Hazardous for human life.

OR

Question:  What are the impacts of mining on the health of the miners and the environment?

Answer: The impacts of mining on the health of the miners and the environment are given below.

The dust and noxious fumes inhaled by miners make them vulnerable to pulmonary diseases.

The risk of collapsing mine roofs, inundation and fires in coalmines are a constant threat to miners.

The water sources in the region get contaminated due to mining. Dumping of waste and slurry leads to degradation of land, soil, and increase in stream and river pollution.

Question: What should government do to prevent mining from becoming a “killer industry”?

Answer: Stricter safety regulations and implementation of environmental laws are essential to prevent mining from becoming a “killer industry”.

Question: Why is the conservation of minerals essential?

OR

Question: Explain the need of conservation of minerals.

OR

Question: Why do we need to conserve mineral resources?

Answer:

         (i)         Mineral resources are finite and non-renewable.

        (ii)        There is a strong dependence of industry and agriculture upon mineral deposits and the substances manufactured from them.

       (iii)       The total volume of workable mineral deposits is an insignificant fraction i.e. one per cent of the earth’s crust.

       (iv)       We are rapidly consuming mineral resources that required millions of years to be created and concentrated.

        (v)        The geological processes of mineral formation are so slow that the rates of replenishment are infinitely small in comparison to the present rates of consumption.

       (vi)       Continued extraction of ores leads to increasing costs as mineral extraction comes from greater depths along with decrease in quality.

Question: Explain the methods of conservation of minerals.

Answer:  Methods of conservation of minerals are given below.

         (i)         A concerted effort has to be made in order to use our mineral resources in a planned and sustainable manner.

        (ii)        Improved technologies need to be constantly evolved to allow use of low grade ores at low costs.

       (iii)       Recycling of metals, using scrap metals and other substitutes are steps in conserving our mineral resources for the future.

Question:  Why do we need Energy Resources?

Answer: Energy is required for all activities.

It is needed to cook,

It is needed to provide light and heat,

It is needed to propel vehicles

It is needed to drive machinery in industries.

Question: How can energy be generated?

Answer: Energy can be generated from fuel minerals like coal, petroleum, natural gas, uranium and from electricity.

Energy can also be generated from Non-conventional sources include solar, wind, tidal, geothermal, biogas etc.

Question: Classify the energy resources available in India. Give examples of each .

Answer: Energy resources can be classified as conventional and non-conventional sources.

 

         (i)         Conventional sources include firewood, cattle dung cake, coal, petroleum, natural gas and electricity (both hydel and thermal).

        (ii)        Non-conventional sources include solar, wind, tidal, geothermal, biogas and atomic energy.

Question: what are most common Energy sources in rural India?

Answer:  Firewood and cattle dung cake are most common in rural India.

Question: Why do the use of firewood and cattle dung cake decreasing in rural areas?

Answer:

         (i)         According to one estimate more than 70 per cent energy requirement in rural households is met by these Non-conventional sources named as Firewood and cattle dung cake.

        (ii)        Continuation of these is increasingly becoming difficult due to decreasing forest area.

       (iii)       Moreover, using dung cake too is being discouraged because it consumes most valuable manure which could be used in agriculture.

Question: What is the importance of coal?

Answer: The importance of coal is discussed below.

         (i)         Coal is the most abundantly available fossil fuel.

        (ii)        It provides a substantial part of the nation’s energy needs.

       (iii)       It is used for power generation, to supply energy to industry as well as for domestic needs.

       (iv)       India is highly dependent on coal for meeting its commercial energy requirements.

Question: Explain the types of coal found in India.

Question: How is coal formed? Describe the qualities of different types of coal found in India.

Answer: Coal is formed due the compression of plant material over millions of years. Coal, therefore, is found in a variety of forms depending on the degrees of compression and the depth and time of burial.

Type of coal (Qualities of Different Types of Coal)

         (i)         Decaying plants in swamps produce peat. This has a low carbon and high moisture contents and low heating capacity.

        (ii)        Lignite is a low grade brown coal. This is soft with high moisture content. The principal lignite reserves are in Neyveli in Tamil Nadu and are used for generation of electricity.

       (iii)       Coal that has been buried deep and subjected to increased temperatures is bituminous coal. It is the most popular coal in commercial use. Metallurgical coal is high grade bituminous coal which has a special value for smelting iron in blast furnaces.

       (iv)       Anthracite is the highest quality hard coal.

Question: Explain the Coal Belts in India.

OR

Question: Describe the distribution of coal in India.

Answer:  In India coal occurs in rock series of two main geological ages, namely Gondwana and Tertiary deposits. 

Gondwana deposits:  A little over 200 million years in age. The major resources of Gondwana coal, which are metallurgical coal, are located in Damodar valley (West Bengal- Jharkhand). Jharia, Raniganj, Bokaro are important coalfields. The Godavari, Mahanadi, Son and Wardha valleys also contain coal deposits.

Tertiary deposits: Tertiary deposits are only about 55 million years old. Tertiary coals occur in the north eastern states of Meghalaya, Assam, Arunachal Pradesh and Nagaland.

Question:Why industries and thermal power stations are located on or near the coalfields?

Answer:  Coal is a bulky material, which loses weight on use as it is reduced to ash. Hence, heavy industries and thermal power stations are located on or near the coalfields.

Question: How Petroleum is Important for in human life?

Answer:

         (i)         Petroleum or mineral oil is the next major energy source in India after coal.

        (ii)        It provides fuel for heat and lighting, lubricants for machinery and raw materials for a number of manufacturing industries.

       (iii)       Petroleum refineries act as a “nodal industry” for synthetic textile, fertiliser and numerous chemical industries.

Question: What are the Areas of occurrences of petroleum in India?

Answer:

         (i)         Most of the petroleum occurrences in India are associated with anticlines and fault traps in the rock formations of the tertiary age.

        (ii)        In regions of folding, anticlines or domes, it occurs where oil is trapped in the crest of the upfold.

       (iii)       The oil bearing layer is a porous limestone or sandstone through which oil may flow.

       (iv)       The oil is prevented from rising or sinking by intervening non-porous layers.

        (v)        Petroleum is also found in fault traps between porous and non-porous rocks. Gas, being lighter usually occurs above the oil.

Question: What are the Major petroleum production areas in India?

Answer:

         (i)         Mumbai High, Gujarat and Assam are major petroleum production areas in India.

        (ii)        Ankeleshwar is the most important field of Gujarat.

       (iii)       Assam is the oldest oil producing state of India. Digboi, Naharkatiya and Moran-Hugrijan are the important oil fields in the state.

Question: Explain Natural Gas as a source of energy in India. Also give its distribution in India. Answer: Natural Gas is found with petroleum deposits and is released when crude oil is brought to the surface.

It can be used as a domestic and industrial fuel.

It is used as fuel in power sector to generate electricity,

It is used for heating purpose in industries,

It is also used as raw material in chemical, petrochemical and fertilizer industries,

It is used as transport fuel and as cooking fuel.

With the expansion of gas infrastructure and local city gas distribution (COD) networks,

Natural gas is also emerging as a preferred transport fuel (CNG) and cooking fuel (PNG) at homes.

Distribution of natural gas in India

India’s major gas reserves are found in the Mumbai High and allied fields along the west coast which are supplemented by finds in the Cambay basin.

Along the East Coast, new reserves of natural gas have been discovered in the Krishna-Godavari basin.

Question: What is HVJ? What does it carry? Give major features of this pipeline.

Answer: Hazira-Vijaipur- Jagdishpur (HVJ) is a pipeline.

 It carries natural gas.

The length of this pipeline is 1,700 km.

 It is a cross country gas pipeline,

It is constructed by GAIL (India).

It is linked Mumbai High and Bassein gas fields with various fertilizer, power and industrial complexes in western and northen India.

This artery provided impetus to Indian gas market development.

Question: Write the importance of Electricity.

Answer: Electricity has such a wide range of applications in today’s world that, its percapita consumption is considered as an index of development.

Question: What are the two ways of electricity generation? What are the differences between from each other?

OR

Question: Distinguish between Hydro Electricity and Thermal Power

Answer: Electricity is generated mainly in two ways: Hydro Electricity and Thermal Power

Hydro Electricity

Electricity is generated by running water which drives hydro turbines to generate hydro electricity.

Hydro electricity is generated by fast flowing water, which is a renewable resource.

India has a number of multi-purpose projects like the Bhakra Nangal, Damodar Valley Corporation, the Kopili Hydel Project etc. producing hydroelectric power.

Thermal Power

Electricity is generated by burning other fuels such as coal, petroleum and natural gas to drive turbines to produce thermal power.

Once generated the electricity is exactly the same.

Thermal electricity is generated by using coal, petroleum and natural gas.

The thermal power stations use non-renewable fossil fuels for generating electricity.

 Question: Why there is a pressing need to use non- conventional sources of energy in recent years in India? Explain the reasons.

Answer: Renewable energy sources like solar energy, wind, tide, biomass and energy from waste material. These are called non-conventional energy sources.

There is a pressing need to use renewable energy sources like solar energy, wind, tide, biomass and energy from waste material.

     (i)            The growing consumption of energy has resulted in the country becoming increasingly dependent on fossil fuels such as coal, oil and gas.

   (ii)            Rising prices of conventional energy sources like coal, oil and gas.

 (iii)            Potential shortages of oil and gas have raised uncertainties about the security of energy supply in future,

 (iv)            It, in turn has serious repercussions on the growth of the national economy.

   (v)            Moreover, increasing use of fossil fuels also causes serious environmental problems.

Question: Define non-conventional energy sources.

Answer: Renewable energy sources like solar energy, wind, tide, biomass and energy from waste material are called non-conventional energy sources.

Question: Which are the two main minerals used to obtain Nuclear or Atomic Energy? Write the name of any two states where these minerals are found.

OR

Question: How does one can obtain nuclear or atomic energy? Name all the six Nuclear power stations of India.

Answer:

         (i)         Nuclear or Atomic Energy is obtained by altering the structure of atoms. When such an alteration is made, much energy is released in the form of heat and this is used to generate electric power.

        (ii)        Uranium and Thorium are used for generating atomic or nuclear power.

       (iii)       Uranium and Thorium are available in Jharkhand and the Aravalli ranges of Rajasthan.

       (iv)       The Monazite sand of Kerala is also rich in Thorium.

Nuclear power stations

     (i)            Tarapur (Maharashtra)

   (ii)            Naraura (Uttar Pradesh)

 (iii)            Kaiga (Karnataka)

 (iv)            Kakrapara (Gujarat)

   (v)            Kalpakkam (Tamil Nadu )

 (vi)            Rawat Bhata   (Rajasthan)

Question: What are the advantages of solar energy?

OR

Question: Why is solar energy fast becoming popular in rural and remote areas?

Solar Energy

India is a tropical country. It has enormous possibilities of tapping solar energy.

Photovoltaic technology converts sunlight directly into electricity.

Solar energy is fast becoming popular in rural and remote areas.

Some big solar power plants are being established in different parts of India which will minimise the dependence of rural households on firewood and dung cakes,

In this way solar energy contribute to environmental conservation and adequate supply of manure in agriculture.

Question: Write about Wind power in India.

Answer:

         (i)         India has great potential of wind power.

        (ii)        The largest wind farm cluster is located in Tamil Nadu from Nagarcoil to Madurai.

       (iii)       Apart from these, Andhra Pradesh, Karnataka, Gujarat, Kerala, Maharashtra and Lakshadweep have important wind farms.

       (iv)       Nagarcoil and Jaisalmer are well known for effective use of wind energy in the country.

Question: Write about biogas as a source of energy in India.

Answer:

         (i)         Shrubs, farm waste, animal and human waste are used to produce biogas for domestic consumption in rural areas.

        (ii)        Decomposition of organic matter yields gas, which has higher thermal efficiency in comparison to kerosene, dung cake and charcoal.

       (iii)       Biogas plants are set up at municipal, cooperative and individual levels.

       (iv)       The plants using cattle dung are known as ‘Gobar gas plants’ in rural India.

        (v)        These provide twin benefits to the farmer in the form of energy and improved quality of manure.

       (vi)       Biogas is by far the most efficient use of cattle dung.

      (vii)      It improves the quality of manure and also prevents the loss of trees and manure due to burning of fuel wood and cow dung cakes.

Question: Examine Tidal Energy as sources of energy of the future.

Answer:

         (i)         Oceanic tides can be used to generate electricity.

        (ii)        Floodgate dams are built across inlets.

       (iii)       During high tide water flows into the inlet and gets trapped when the gate is closed.

       (iv)       After the tide falls outside the flood gate, the water retained by the floodgate flows back to the sea via a pipe that carries it through a power-generating turbine.

        (v)        In India the Gulf of Khambhat, the Gulf of Kuchchh in Gujarat on the western coast and Gangetic delta in Sunderban regions of West Bengal provide ideal conditions for utilising tidal energy.

Question: Write about Geothermal energy as a source of energy in India.

Answer:

         (i)         Geo thermal energy refers to the heat and electricity produced by using the heat from the interior of the Earth.

        (ii)        Geothermal energy exists because; the Earth grows progressively hotter with increasing depth. Where the gradient is high, high temperatures are found at shallow depths.

       (iii)       Groundwater in such areas absorbs heat from the rocks and becomes hot.

       (iv)       It is so hot that when it rises to the earth’s surface, it turns into steam.

        (v)        This steam is used to drive turbines and generate electricity.

       (vi)       There are several hundred hot springs in India, which could be used to generate electricity.

      (vii)      Two experimental projects have been set up in India to harness geothermal energy. One is located in the Parvati valley near Manikaran in Himachal Pradesh and the other is located in the Puga Valley, Ladakh.

Question: There is an urgent need to develop a sustainable path of energy development and energy conservation. Discuss it.

Answer:

     (i)            Energy is a basic requirement for economic development.

   (ii)            Every sector of the national economy – agriculture, industry, transport, commercial and domestic – needs inputs of energy.

 (iii)            The economic development plans implemented since Independence necessarily required increasing amounts of energy to remain operational.

 (iv)            Thus, consumption of energy in all forms has been steadily rising all over the country.

   (v)            In this background, there is an urgent need to develop a sustainable path of energy development.

 (vi)            Promotion of energy conservation increased use of renewable energy sources are the twin planks of sustainable energy.

(vii)            We have to adopt a cautious approach for the judicious use of our limited energy resources.

Question: “Energy saved is energy produced” justify the statement by giving any six measures to conserve the energy resources.

Answer: India is presently one of the least energy efficient countries in the world.

We have to adopt a cautious approach for the judicious use of our limited energy resources.

As responsible citizens of India we can play an important role in the conservation of energy resources by following measures.

     (i)            Use public transport systems instead of individual vehicles;

   (ii)            Switching off electricity when not in use,

 (iii)            We can save energy by using power-saving devices

 (iv)            We can save energy by using non-conventional sources of energy.

   (v)            After all, “energy saved is energy produced”. must be our motto of life.

Question: Which one of the following minerals is formed by decomposition of rocks, leaving a residual mass of weathered material?

(a) coal            (b) bauxite       (c) gold           (d) zinc

Answer: bauxite

Question: Koderma, in Jharkhand is the leading producer of which one of the following minerals?

(a) bauxite       (b) mica           (c) iron ore      (d) copper

Answer: mica

Question: Minerals are deposited and accumulated in the stratas of which of the following rocks?

(a) sedimentary rocks      (b) metamorphic rocks       (c) igneous rocks      (d) none of the above

Answer:  sedimentary rocks

Question:  Which one of the following minerals is contained in the Monazite sand?

(a) oil   (b) uranium      (c) thorium     (d) coal

Answer: thorium

Question: Distinguish between the ferrous and non-ferrous minerals

Answer: Difference between the ferrous and non-ferrous minerals are given below.

Ferrous Minerals

Those minerals which have iron content are known as Ferrous Minerals.

Iron Ore, Manganese, nickel and cobalt are the major Ferrous Minerals.

Ferrous minerals account for about three fourths of the total value of the production of metallic minerals. They provide a strong base for the development of metallurgical industries.

India exports substantial quantities of ferrous minerals after meeting her internal demands.

Non- ferrous minerals

Minerals which do not have iron contents are called non- ferrous metallic minerals.

Copper, led, tin and Bauxite etc. are example of non- ferrous metallic minerals.

In India reserves and production of non-ferrous minerals is not very satisfactory.

Question: Distinguish between the Metallic and Non-Metallic  minerals.

Answer: Difference between the Metallic and Non-Metallic minerals are given below.

Metallic minerals	Non-Metallic minerals
(i)         Minerals which contain metal contents are called as Metallic minerals.	(i)         Minerals which do not contain metal contents are called as Non-Metallic minerals.
(ii)        Iron ore, manganese, nickel, cobalt copper, led, tin bauxite silver and gold etc. are example of Metallic minerals.	(ii)        Mica, limestone, potash, sulphur, granite, lime stone marbel and sand stone ect. are the examples of Non- Metallic minerals.
(iii)       Metallic minerals have distinctive features such as luster, ductile, malleable and good conductor of electricity.	(iii)       Non-Metallic minerals do not have such features.

 Question: Distinguish between the conventional and non-conventional sources of energy.

Answer: Difference between the Conventional energy sources and Non-Conventional energy sources are given below.

Conventional energy sources	Non- Conventional energy sources
(i)            Conventional sources of energy are those sources which have been use from ages.	(i)            Conventional resources of energy have generally been identified in the recent past.
(ii)            These sources are exhaustible.	(ii)            These sources are inexhaustible.
(iii)            These resources are more expensive to be maintained, stored and transmitted as they are carried over long distances through grid and lines.	(iii)            These resources are less expensive to be maintained, these can be used at local level. It easy to maintained these.
(iv)            Coal, petroleum, natural gas atomic power, cow dung cake, firewood etc. are the example of  Conventional sources of energy	(iv)            Solar energy, geothermal energy, wind energy,  tidal energy and biogas are the examples of non-Conventional sources of energy

 

Question: Why do you think that solar energy has a bright future in India?

Answer: India is a tropical country. It has enormous possibilities of tapping solar energy.

Photovoltaic technology converts sunlight directly into electricity. Solar energy is fast becoming popular in rural and remote areas.

Some big solar power plants are being established in different parts of India which will minimise the dependence of rural households on firewood and dung cakes, which in turn will contribute to environmental conservation and adequate supply of manure in agriculture.

 Question: What is the importance of minerals in life process?

OR

Question: What is the importance of minerals in our food?

Answer: All living things need minerals. Because the life processes cannot occur without minerals. Although our mineral intake represents only about 0.3 per cent of our total intake of nutrients, they are so potent and so important that without them we would not be able to utilise the other 99.7 per cent of foodstuffs.