Sources of Energy Part-1
NCERT solutions for Class 10 Science Sources of Energy
NCERT Class 10 Science Chapter wise Solutions
- 1 – Chemical Reactions and Equations
- 2 – Acids, Bases and Salts
- 3 – Metals and Non-metals
- 4 – Carbon and Its Compounds
- 5 – Periodic Classification of Elements
- 6 – Life Processes
- 7 – Control and Coordination
- 8 – How do Organisms Reproduce?
- 9 – Heredity and Evolution
- 10 – Light Reflection and Refraction
- 11 – Human Eye and Colourful World
- 12 – Electricity
- 13 – Magnetic Effects of Electric Current
- 14 – Sources of Energy
- 15 – Our Environment
- 16 – Management of Natural Resources
NCERT Solutions for Class 10 Science Sources of Energy Part 1
1. What is a good source of energy?
Ans. A good source of energy should have the following qualities:
(a) It should be easily available.
(b) It should have high calorific value.
(c) It should be easy to store and transport
(d) It should be economical
(e) It should not cause environmental pollution
2. What is a good fuel?
Ans. A good fuel is that which release more heat on burning, is easily available at the economical rate and do not cause environmental pollution.
NCERT Solutions for Class 10 Science Sources of Energy Part 1
3. If you could use any source of energy for heating your food, which one would you use and why?
Ans. We shall use LPG/PNG gas or electricity for heating your food because these are pollution free and have high calorific value.
1. What are the disadvantages of fossil fuels?
Ans. There are following disadvantage of fossil fuels:
(a) Burning of fossil fuels causes’ pollution.
(b) Oxides of Sulphur and nitrogen produced on burning of fossil fuel causes acid rain.
(c) Carbon dioxide causes greenhouse effect.
(d) Fossil fuels are non-renewable sources of energy.
2. Why are we looking at alternate sources of energy?
Ans. Fossil fuels are non-renewable sources of energy and their reserves are limited one. Hence, we need to conserve them. If we continue consuming these sources at same rate as presently, we may soon run out of energy. To avoid such a situation, we are looking for alternative sources of energy.
NCERT Solutions for Class 10 Science Sources of Energy Part 1
3. How has the traditional use of wind and water energy been modified for our convenience?
Ans. To use energy of flowing water large dams are built in hilly regions to store huge amount of water at a height. This water is used to produce hydroelectricity.
Wind energy is used to generate electricity by using windmill that converts the wind energy into electricity.
1. What kind of mirror –concave or convex or plain –would be best suited for use in a solar cooker? Why?
Ans. Large size concave mirrors are best suited for use in solar cooker, because they focus large amount of solar radiation on a small surface area so temperature will rise quickly.
2. What are limitations of the energy that can be obtained from the oceans?
Ans. Limitations of energy obtained from oceans:
(a) There are very few locations where dams to utilize tidal energy can be built.
(b) Cost of installation of power houses is extremely high and efficiency of plants is comparatively small.
(c) Power plants built in oceans will need high continuous maintenance.
3. What is geothermal energy?
Ans. Geothermal energy is the heat energy present inside the earth in certain regions called hot spots. When underground water comes in contact with the hot spot, steam is generated. This steam is routed through a pipe to a turbine and used to generate electricity.
NCERT Solutions for Class 10 Science Sources of Energy Part 1
4. What are the advantages of nuclear energy?
Ans. Main advantages of nuclear energy are as follows:
(a) For given mass fuel consumed the amount of energy released is very large.
(b) Nuclear power plants can be designed and constructed at any place.
(c) If proper precautions are taken while running nuclear power plants, a major fraction of energy need can be obtained from nuclear energy sources.
1. Can any source of energy be pollution free? Why or why not?
Ans. No, source of energy is completely pollution free. A source of energy to be pollution free if neither it causes any pollution during its actual operation nor there any pollution during assembly of devices utilizing that source of energy. Solar cell device may have caused some pollution.
2. Hydrogen has been used as rocket fuel; would you consider it a clear fuel than CNG? Why of why not?
Ans. Hydrogen can be considered a cleaner fuel because its burning produces water vapour which is non-polluting. However, due to explosive nature of hydrogen, its storage and transportation is difficult.
1. Name two energy sources that you would consider to be renewable. Give reasons for your choices.
Ans. Solar energy, wind energy, ocean energy etc. are renewable sources of energy due to the following reasons:
(a) These forms of energy are available in plenty in our natural environment.
(b) These energy sources will not be depleted because their supply is large and extraction of usable energy from these sources is negligible.
2. Give the names of two energy sources that you would consider to be exhaustible. Give reasons for your choices.
Ans. Coal and petroleum are two exhaustible sources of energy. These fuels were formed over million for years ago and there are only limited reserves. If we continue to use them as at present, these reserves will be exhausted soon.