Here you will find all the questions, solutions, answers, and notes of chapter 6 Power Resources of Social Science for class 10 students studying under Nagaland Board of School Education (NBSE). However, the study materials should be used only for references and nothing more. The notes can be modified/changed according to needs.
INTRODUCTION: The capacity for doing work or a force that produces an activity is known as energy. Humans use a variety of energy sources to do work, including chemical energy (fossil fuels and wood), geothermal energy, tidal power, hydroelectric power, nuclear energy, solar energy and wind power.
Two traditional sources of energy used in rural India are firewood and cow dung cake. It is estimated that these two sources provide 70 per cent of the energy required in rural households. Decreasing forest area and requirement of dung for manures have generated the need for other energy sources in the villages. Energy is needed to provide light and heat, to propel vehicles, and to make machines work
I. Multiple Choice Questions
1. Which of the following is a conventional source of energy?
Answer: (a) coal
2. Which of the following is a conventional source of energy widely used in rural areas?
Answer: (b) Firewood
3. The gas supplied for use in households is called-
Answer: (a) LPG
4. Which of the following is a clean energy resource?
Answer: (b) Natural gas
5. Which of the following is the most abundantly available fossil fuel in India? [HOTS]
Answer: (b) Coal
6. Which of the following is an environment-friendly fuel?
Answer: (c) Natural gas
II. Very Short Answer Questions
1. Where is the largest solar power plant located in India?
Answer: The largest solar plant of India is located at Madhapur near Bhuj.
2. What is tidal energy?
Answer: Tidal energy is a form of hydropower that transforms the energy obtained from oceanic tides into useful forms of power.
3. What is biogas?
Answer: Biogas is a gas produced when organic matter decomposes. This gas is higher in thermal efficiency when compared to charcoal, kerosene and cow dung.
III. Short Answer Questions
1. Why are thermal power plants located near coalfields?
Answer: Coal is a heavy and bulky material but after use, it becomes ash. Hence, if heavy industries or thermal power stations are located on or near the coalfields the cost and problems of transportation of this fuel becomes almost negligible.
2. Why is petroleum refineries termed as ‘nodal industries’? [HOTS]
Answer: Petroleum refineries serve as ‘nodal industry’ for other industries like chemical, fertilisers, etc. Therefore, the petroleum refineries are termed as ‘nodal industries’.
3. What factors make the production of solar energy convenient in India?
Answer: The following factors make the production of solar energy convenient in India:
i. India being a tropical country is well endowed with plenty of solar energy throughout the year.
ii. India has access to photovoltaic technology which directly converts sunlight into electricity.
IV. Long Answer Questions
1. What is crude oil? Where in India is petroleum drilled?
Answer: Crude oil is a naturally occurring petroleum that is not refined. It is a type of fossil fuel that can be refined to make different products like diesel, gasoline etc.
In western India, Mumbai High, Bassein and Aliabet are important off-shore oil fields. In Gujarat, important oil fields are in Ankleshwar near Vadodara. This oil is refined at Trombay and Koyali. Lunej and Kalol oil fields are located near Ahmedabad. Assam, in north-eastern India, is the oldest oil-producing state of India. It has three important oil fields – Naharkatiya, Moran-Hugrijan and Digboi. Oil from these fields is refined at Digboi, Numaligarh, Guwahati and Bongaigaon in Assam and Barauni in Bihar. There are 18 oil refineries in the country.
2. What is natural gas? Where is it extracted in India?
Answer: Natural gas is a clean energy resource found associated with or without petroleum. Natural gas can be extracted easily by drilling wells.
India produced about 31.90 billion cubic metres of natural gas in 2016-17. More than 3/4th of the production comes from Mumbai High, 10 per cent from Gujarat, 7 per cent from Assam and the remaining from Andhra Pradesh, Tamil Nadu, Tripura and Rajasthan. Large reserves of natural gas have been discovered in Krishna-Godavari Basin and Gulf of Cambay. Andaman and Nicobar Islands also have reserves of natural gas.
3. Distinguish between hydroelectricity and thermal electricity.
|Generated by fast-flowing water.||Generated by using coal, petroleum and natural gas to drive turbines and produce thermal power.|
|Renewable resource is used to produce this electricity.||Non-renewable fossil fuel is used to produce this electricity.|
|Multipurpose projects like the Bhakra Nangal, Damodar Valley Corporation, Kopili Hydel Project, etc., produce this kind of electricity.||There are over 310 thermal power plants in India, e.g., Loktak, Santhaldih, Talcher, Neyveli, Ukai, Dhuvaram, etc.|
4. ‘Biogas is considered as an ideal domestic fuel.’ Give four reasons in support of the statement.
Answer: Four reasons in support of the statement that ‘biogas is considered as an ideal domestic fuel’ are:
i. Shrubs, farm waste, animal and human waste is utilised to produce biogas for domestic consumption in rural areas.
ii. This gas is higher in thermal efficiency when compared to charcoal, kerosene and cow dung.
iii. Gobar gas plants use cow dung and give twin benefits to the farmers – energy and manure.
iv. Such plants can be set up at individual, cooperative and municipal levels.
5. Differentiate between conventional and non-conventional sources of energy.
|Conventional sources of energy||Non-conventional sources of energy|
|They are non-renewable sources of energy.||They are renewable sources of energy.|
|They are going to last just for 100 to 200 years.||They are going to last forever.|
|They cause widespread air and water pollution.||They are environment-friendly and it does not cause pollution.|
|They include fossil fuels like coal, petroleum, and natural gas.||They include solar energy, wind energy, geothermal energy, and biogas energy.|
6. Describe the importance of coal as a source of energy.
Answer: One-third of the energy used throughout the world comes from coal. In addition to supplying fuel, coal is used in the production of many chemical products, including medicines and pesticides. India is highly dependent upon coal for meeting its commercial energy requirements, e.g., power generation and supplying energy to industries as well as for domestic needs.
7. How is petroleum an important source of both energy and raw material? [HOTS]
Answer: Petroleum is an important source of both energy and raw material. On account of the various by-products obtained during the refining process, petroleum refineries serve as ‘nodal industry’ for chemical, fertiliser and synthetic textile industries. It provides fuel for heating, lighting, running different types of machinery and vehicles, lubricants for machinery and raw materials for manufacturing different products such as plastics, chemicals, etc.
8. ‘Natural gas is a clean gas.’ Write a note on the significance of natural gas.
Answer: Natural gas is a clean energy resource found associated with or without petroleum. Natural gas can be extracted easily by drilling wells. One advantage of natural gas is that it does not require processing, as do coal and oil. After being cleared of impurities, natural gas is ready for the consumer. While burning it does produce carbon dioxide and it burns hotter and clearer than other fossil fuels. It is also cheaper. Natural gas is also used to generate electricity. While natural gas has many advantages it is limited.