NCERT Class 10 Science Chapter 14 Sources of Energy Question Answer Solution For School Students of Class 10th. We also Provides Notes and Important Questions for Class 10 Science. NCERT Class 10th Science book is applied in mostly boards like CBSE, HBSE, RBSE, Up Board, MP Board and also some other state boards. Class 10 Science Chapter 14 Chapter Inside Questions Solution.
Also Read:- Class 10 Science NCERT Solution
NCERT Class 10 Science Chapter 14 Sources of Energy Internal Question and Answer for CBSE, HBSE and Other Boards Solution.
Sources of Energy Class 10 Science Question Answer
Q. 1. What is a good source of energy ?
Ans. Good source of energy or fuel is one :
(i) which releases a large amount of heat per unit mass of source of energy or fuel consumed.
(ii) which does not produce smoke. It should not produce any poisonous gas like carbon monoxide, sulphur dioxide or nitrogen peroxide.
(iii) which is easily available.
(iv) which does not cost much.
(v) which could be easily transported from one place to
Q. 2. What is a good fuel ?
What is an ideal fuel ? Give one example.
Ans. 1. Its calorific value should be large.
2. It should burn easily.
3. It should produce no smoke and should not leave any residue.
4. It should be economical costwise.
5. It should produce pollution.
6. It should have low ignition temperature.
7. It should be easy to store and produce no hazard to transport it.
8. It should burn at controllable rate.
Q. 3. If you could use any source of energy for heating your food, which one would you use and why ?
Ans. Fuel to be used should be easily accessible, should be easy to store and transport and should be economical.
If we are in city area, L.P.G. should be used since it does not produce pollution, is easily
available and is economical. In rural area, Gobar gas or biogas should be used. It is almost free, has high calorific and is pollution free. It is also renewable source of energy.
Q. 1. What are disadvantages of fossil fuels ?
What are the disadvantages (hazards of using fossil fuels)?
Ans. Though fossil fuel is very largely being used as a source of energy, there are number of disadvantages of using them.
1. There are only limited reserves of fossil fuel. These fuels were formed over millions of year. If we continue to use them at present rate, we would soon run out of energy.
2. Fossil fuel is non-renewable source of energy.
3. Fossil fuels cause air pollution.
4. Oxides of carbon, nitrogen and sulphur released on burning of fossil fuel are acidic oxides. These lead to acid rain affecting our water and soil resources.
5. Carbon dioxide produced by burning of fossil fuel causes green house effect.
Q. 2. Why are we looking at alternative sources of energy ?
Ans. We are looking for alternative sources of energy because Conventional sources of energy :
- like coal and petroleum are not going to last long.
- are mostly non-renewable sources of energy.
- cause pollution. They are costly.
Q. 3. How has the traditional use of wind and water energy been modified for our convenience ?
Ans. Wind blows due to unequal heating of land mass and water. The energy of the wind can be usefully employed by working of wind-mills. Wind mill helps us to produce electricity. Energy of the wind can be used to do mechanical work i.e., to lift water from the well and run a grain grinding machine. Water energy can be used to produce electric power in hydro power plants. Water is collected in dams and later its potential energy can be converted into electric energy. Energy of tides in the sea can also be converted to electricity. During high tides, the water is stored and during low tides, the energy of the stored water is used to convert it into electricity.
Q. 1. What kind of mirror-concave, convex or plane would be best suited for use in a solar cooker ? Why ?
Ans. Concave mirror is best suited since it can focus sun rays from large area to a specific area. However plane mirror may also be used but in no case convex mirror be used. Convex mirror diverges the rays and hence will not transfer sufficient heat to the cooker.
Q. 2. What are the limitations of the energy that can be obtained from the oceans ?
Ans. Due to attraction of the moon, there are high and low tides in the sea. Tidal energy harnessed by constructing a dam across a narrow opening to the sea. A turbine fixed at the opening of the dam converts tidal energy to electricity. The limitation to such dams is due to scarcity of locations where such dams can be constructed.
Ocean thermal energy of the sea or ocean is also used to produce electricity but these plants operate if the temperature difference between water at the surface and water at the depth upto 2 km is 20°C or more.
Q. 3. What is geothermal energy?
Ans. Due to changes taking place within earth, molten rocks formed in the deeper hot regions of earth are pushed upward in the regions called ‘hot spots’. Steam is generated when underground water comes in contact with hot spots. Steam trapped in rocks is routed through a pipe to the turbine and used to generate electricity. Though the cost is not so much but commercially suitable sites have to be located.
Q. 4. What are the advantages of nuclear energy?
Ans. Nuclear energy is preferred to fossil energy, hydro energy, thermal energy etc. for the following reasons.
1. A smaller space is required to get nuclear energy as compared to harness hydro energy,
thermal energy etc.
2. It produces much more energy than other conventional sources.
3. It costs less.
4. It causes less pollution than fossil energy.
Q. 1. Name two energy sources that you would consider to be renewable. Give reasons for your choice.
Write the name of two renewable source of energy.
Ans. Solar energy, wave energy, tidal energy, wind energy all are renewable sources of energy. The solar energy is free and can be used anywhere with ease. Solar energy can be used to produce electric energy in solar cells. It can be used for solar water heaters and in solar cookers. Wind is also available source of energy almost everywhere and can be used to run wind farms to produce electricity, to draw water from the wells and grind the grains.
Q. 2. Give the names of two energy sources that you would consider to be exhaustible. Give reasons for your choice.
Ans. Coal and petroleum are two energy sources which are exhaustible. It takes millions of years for formation of petrol and coal inside the earth. Its reserves are limited. Coal if used at present rate will not last beyond two hundred years where as petroleum products which are being used extensively are not expected to last more than 50 years.
Wood though considered to be a renewable source of energy should be used with at most caution. Whereas it takes more than 10 years for a tree to grow up, it takes a few hours to burn it up.
Q. 1. Can any source of energy be pollution free ? Why or why not ?
Ans. No source of energy can be perfectly pollution free but bio-mass energy, hydro energy, wind energy, geothermal energy, solar energy is almost pollution free. If fossil fuel is allowed to burn in presence of excess of oxygen, the pollution produced can be very much reduced.
Q. 2. Hydrogen has been used as a rocket fuel. Would than C.N.G.? Why or why not ? you consider it a cleaner fuel.
Ans. Hydrogen is a cleaner fuel because it does not pollute the atmosphere. Hydrogen when burnt in presence of oxygen produces harmless water vapours. On the other hand, C.N.G. when burnt produces carbon mono-oxide, carbon dioxide, oxides of sulphur and nitrogen. Except carbon dioxide, all pollute the atmosphere. However carbon dioxide does produce green house effect.