Energy Resources Q & A
(A) What resource will have to be used for the following work:
(1) Rohan wants to fly a kite.
Ans: Wind.
(2) People in an Adivasi hamlet have to be protected from the cold.
Ans: Wood.
(3) Cooking on a picnic.
Ans: Wood.
(4) Salma wants to iron her clothes.
Ans: Electricity.
(5) Starting a railway-engine.
Ans: Thermal Energy.
(6) Heating water for a bath.
Ans: Electricity.
(7) After sunset, making light available inside the house.
Ans: Electricity.
(B) Answer the following questions:
(1) Which energy resources does man use the most? Why?
Ans: Coal is the energy resources that man uses the most because it is comparatively easily available everywhere in greater quantities.
(2) Why are energy resources needed?
Ans: The energy resources are needed to satisfy the needs of man like heating water, cooking food, ironing dress, etc.
(4) Why do we need to use environment friendly energy resources?
Ans: We need to use environment-friendly energy resources because it will not only lead to sustainable development but also provide energy security which is the need of the hour.
(C) Explain the differences using the points in the brackets:
(availability, environment-friendliness,advantages and drawbacks)
(1) Mineral oil and solar energy
Ans:
Points | Mineral oil | Solar energy |
Availability | (1) Limited in nature as it does not last perpetually. | (1) Availability depends on the intensity of sunrays and the duration of sunshine. |
Environment-friendliness | (1) It is not environment friendly as its generation leads to pollution. (2) Being highly inflammable it may cause damage to the environment. | (1) Being pollution-free this is an environment-friendly source of energy. |
Advantages | (1) Cheap source of energy. (2) Aids in thermal and atomic power generation. | (1) A solution to global warming. energy security. |
Drawbacks | (1) Pollutes the environment. (2) Highly inflammable. | (1) Solar panels stop producing electricity after sunset. (2) Expensive to store this energy. |
(2) Hydel power and power from geothermal source
Ans:
Points | Hydel power | Power from geothermal sources |
Availability | (i) Obtained from the kinetic energy of running water which is easily available. | (i) Underground heat is utilized to generate power and it is inexhaustible. |
Environment-friendliness | (i) Does not cause any degradation of the environment. | (i) It is an exhaustible energy resource that causes minimum pollution. |
Advantages | (i) Reuse of water is possible. Easy availability of water in most places. Energy generation is pollution-free. | (i) If used on a large scale and more efficiently it may reduce global warming. |
Disadvantages | (i) When water is not available it can’t produce electricity. | (i) Only a few sites have the potential to establish geothermal power plants. (ii) High installation cost is involved. (iii) The energy generation capacity is too small. |