"AKC SCIENCE CLASSES"
CLASS 10 TH (CBSE AND MP BOARD)
CHAPTER 14
SOURCES OF ENERGY
EXERCISES QUESTIONS AND ANSWERS
Q.01:- A solar water heater cannot be used to get hot water on
(a) a sunny day
(b) a cloudy day
(c) a hot day
(d) a windy day.
Ans:- (b) a cloudy day.
Q.02:- Which of the following is not an example of a bio-mass energy source?
(a) Wood
(b) Gobar gas
(c) Nuclear energy
(d) Coal
Ans:- (c) nuclear energy.
Q.03:- Most of the sources of energy we use represented stored solar energy. Which of the following is not ultimately derived from the Sun's energy?
(a) Geothermal energy
(b) Wind energy
(c) Nuclear energy
(d) Bio-mass
Ans:- (a) Geothermal energy.
Q.04:- Compare and contrast fossil fuels and the Sun as direct sources of energy.
Ans:-
| SL No. | Fossil fuels | Sun |
|---|---|---|
| 1 | Non-renewable | Renewable |
| 2 | Causes lot of air pollution | Pollution free |
| 3 | Easily tapped | Difficult to tap |
Q.05:- Compare and contrast bio-mass and hydro electricity as sources of energy.
Ans:- Bio-mass as source of energy :- Renewable and clean source of energy but rate of availability is moderate.
Hydro electricity as source of energy :- Renewable and clean source, can be produced on a large scale but can be tapped at limited sites. Causes a lot of environmental damage.
Q.06:- What are the limitations of extracting energy from :-
(a) the wind?
(b) waves?
(c) tides?
Ans:- (a) Limitations of wind energy :-
(ⅱ) can be tapped only during specific periods when speed is above 15km/h.
(ⅲ) wear and tear of windmill parts is quite high.
(b) Limitations of wave energy :- Wave energy is viable proposition only when and where the waves are very strong. This has constraints of time and location.
(c) Limitations of tidal energy :- Tidal energy has limitations on the height of tides and the locations where such dams can be built. Huge amount of silt gets deposited on basins in the dams.
Q.07:- On what basis would you classify energy sources as
(a) renewable and non-renewable?
(b) exhaustible and inexhaustible?
Are the options given in (a) and (b) the same?
Ans:- (a) Renewable sources :- These sources can be harnessed into energy so long as the present solar system exists. The energy derived from flowing water, wind, tides, ocean waves, wood or atomic energy are such sources.
Non-renewable sources :- These sources are produced over millions of years under special conditions. Once consumed are not replaceable for a very long time. Fossil fuels like coal, petroleum and natural gas are non-renewable sources.
(b) Exhaustible sources are non-renewable sources while inexhaustible sources are renewable sources.
Q.08:- What are the qualities of an ideal sources if energy?
Ans:- An ideal sources of energy are :-
- must give an adequate amount of net energy.
- must be convenient to use so as to give energy at a steady rate.
- must be easy to store and transport.
Q.09:- What are the advantages and disadvantages of using a solar cooker? Are there places where solar cookers would have limited utility?
Ans:- Advantages :- Solar cooker provides cost free, pollution free heating device.
Q.10:- What are the environmental consequences of the increasing demand for energy? What steps would you suggest to reduce energy consumption?
Ans:- No matter matter what source of energy is used, increasing demand would disturb the environment in some way or the other. Either it would cause more pollution or cause environmental damage. Development and consumption of energy would go together. Therefore, we should concentrate more on finding better and alternative sources of energy. When looking for alternative sources, the following points should be kept in mind :-
(ⅱ) The efficiency of the available technology.
(ⅲ) Environmental impact of using that source.
