NCERT Solutions for Class 10 Social Science Chapter 5 - Minerals and Energy Resources

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(b) Bauxite

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(b) Mica

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(a) Sedimentary rocks

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(c) Thorium

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Ferrous Minerals:

- The metallic minerals, which have iron (Ferrous) content are called Ferrous Minerals (Fe).

- Iron, Manganese, Chromite, Cobalt, etc. are ferrous minerals.

- These are used in the Iron and Steel industry. Some minerals are used as alloys in making different types of steel.

Non-Ferrous Minerals:

- The minerals, which do not have Iron (Ferrous) are called Non-Ferrous Minerals (NFe).

- Copper, Lead, Zinc and Aluminium are non-ferrous minerals.

- Each mineral has its particular utility. Some minerals are valuable according to their uses.

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Conventional Sources of Energy:

- The sources of energy, which have been used since a long time are called the conventional sources of energy.

- Wood fuel, coal, petroleum, natural gas and hydro-electricity are conventional sources of energy.

- These resources are exhaustible or non-renewable resources.

- Once exhausted, these take many years to be replenished.

- These are expensive.

Non-Conventional Sources of Energy:

- The sources of energy, which have not been commonly used are called non-conventional sources of energy.

- Wind, tidal power, Geo-thermal energy, bio-gas, solar energy etc. are non-conventional sources of energy.

- These are inexhaustible or renewable resources.

- Once exhausted, these take many years to be replenished.

- These are inexpensive.

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Mineral is a homogenous and a naturally occurring substance with a definable internal structure. Minerals range from the hardest i.e., diamond to the softest i.e., talc.

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In igneous and metamorphic rocks, minerals may occur in the cracks, crevices, faults or joints. The smaller occurrences are called veins and the larger occurrences are called lodes. Minerals like Tin, Copper, Zinc and Lead are obtained from veins and lodes.

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Minerals are a finite and non-renewable resource. We are using these resources at a very fast rate. If used injudiciously, these will not last long. Mineral formation and the rate of replenishment is very slow. We must conserve mineral resources for our existence and for the use by our future generations.

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Coal is the prime source of energy. It is often called the ‘Mother of Industries’. It has been the basis of industrial revolution. Coal is used as a raw material in iron and steel, chemical and thermal industries. India ranks seventh in the world, as regards to coal reserves. The total proven coal reserves are nearly 2,14,000 million tonnes. These reserves will not last long.

Coal producing states: The major states known for coal reserves are Jharkhand, Bihar, Odisha, West Bengal, Chhattisgarh, Madhya Pradesh, Telangana, Andhra Pradesh and Maharashtra. Production: Coal production started in 1774 in the Raniganj coal fields of West Bengal. After independence, the production of coal has increased ten times. The per capita consumption of coal has increased from 135 kgs to nearly 225 kgs.

Distribution: India has two types of coal fields:

(A) Gondwana coal fields (98%): These belong to the Gondwana period (200 million years ago). Nearly 3/4th of coal deposits are found in the Damodar valley (Damuda series). Godavari, Mahanadi, Son and Wardha valley also have coal deposits.

1. West Bengal: West Bengal has the oldest coal field of India at Raniganj. It covers an area of 1,267 sq. kms. Asansol and Durgapur are steel centres of West Bengal.
2. Jharkhand and Bihar: These two states produce 50% of coal in India. The major coalfields of Jharia, Bokaro, Karanpura and Daltonganj are found in the Damodar valley. Coking coal from this coalfield is supplied to the steel centres of Jamshedpur and Bokaro.
3. Chhattisgarh and Madhya Pradesh: These have the Son valley coalfields of Sohagpur, Korba, Rampur, Tatapani and Singrauli.
4. Singareni in Andhra Pradesh: Talcher in the Mahanadi valley and Chanda-Wardha coalfields of Maharashtra.

(B) Tertiary coalfields (2%): This includes lignite deposits called ‘brown coal’, which is of low quality.

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Solar Energy is the most abundant, cheapest and inexhaustible source of energy produced from sunlight. Solar cookers are used in cooking food. Solar power is being used for cooking, water heating, water desalination, space heating and crop drying. Solar energy is going to be the energy of the future. Reasons:

1. India is a tropical country. It receives bright sunshine throughout the year.
2. Photovoltaic technology converts sunlight directly into electricity.
3. The largest solar plant of India is at Madhapar (Bhuj). It is used to sterilise milk cans.
4. Rural households will save fire wood and dung cakes.
5. India does not have adequate resources of coal and petroleum. So we must develop solar powe

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Some river valley projects and dams built on these rivers are:

1. Hirakund Project– Hirakund dam on Mahanadi river
2. Bhakra Nangal Project – Bhakra and Nangal dams on Satluj river
3. Sardar Sarovar Project – Sardar sarovar dam on Narmada river
4. Damodar Valley Project – On Damodar river in Bihar