Sources of Energy MCQ
9. Which part of the solar cooker is responsible for green house effect?
(a) Coating with black colour inside the box
(b) Mirror
(c) Glass sheet
(d) Outer cover of the solar cooker
Ans. (c) Glass sheet
10. The main constituent of biogas is
(a) methane
(b) carbon dioxide
(c) hydrogen
(d) hydrogen sulphide
Ans. (a) Methane
11. The power generated in a windmill
(a) is more in rainy season since damp air would mean more air mass hitting the blades
(b) depends on the height of the tower
(c) depends on wind velocity
(d) can be increased by planting tall trees close to the tower
Ans. (c) depends on wind velocity
Explanation: Higher wind velocity will turn the turbine at higher speed. This will help in more power generation.
12. Choose the correct statement
(a) Sun can be taken as an inexhaustible source of energy
(b) There is infinite storage of fossil fuel inside the earth
(c) Hydro and wind energy plants are non polluting sources of energy
(d) Waste from a nuclear power plant can be easily disposed off
Ans. (a) Sun can be taken as an inexhaustible source of energy
13. In a hydroelectric power plant more electrical power can be generated if water falls from a greater height because
(a) its temperature increases
(b) larger amount of potential energy is converted into kinetic energy
(c) the electricity content of water increases with height
(d) more water molecules dissociate into ions
Ans. (b) larger amount of potential energy is converted into kinetic energy
Explanation: Potential energy increases with increase in height.
14. Choose the incorrect statement regarding wind power
(a) It is expected to harness wind power to minimum in open space
(b) The potential energy content of wind blowing at high altitudes is the source of wind power
(c) Wind hitting at the blades of a windmill causes them to rotate the rotation thus achieved can be utilised further
(d) One possible method of utilising the energy of rotational motion of the blades of a windmill is to run the turbine of an electric generator
Ans. (b) The potential energy content of wind blowing at high altitudes is the source of wind power
Explanation: A windmill works on kinetic energy of wind.
15. Choose the incorrect statement
(a) We are encouraged to plant more trees so as to ensure clean environment and also provide bio-mass fuel
(b) Gobar-gas is produced when crops, vegetable wastes etc., decompose in the absence of oxygen
(c) The main ingredient of bio-gas is ethane and it gives a lot of smoke and also produces a lot of residual ash
(d) Bio-mass is a renewable source of energy
Ans. (c) The main ingredient of bio-gas is ethane and it gives a lot of smoke and also produces a lot of residual ash
Explanation: The main ingredient of biogas is methane. It burns without smoke and leaves no residue.
