KSEEB Solutions for Class 10 Science Chapter 14 Sources of Energy

Students can Download Science Chapter 14 Sources of Energy Questions and Answers, Notes Pdf, KSEEB Solutions for Class 10 Science helps you to revise the complete Karnataka State Board Syllabus and to clear all their doubts, score well in final exams.

Karnataka State Syllabus Class 10 Science Chapter 14 Sources of Energy

KSEEB Class 10 Science Sources of Energy Intext Questions and Answers

Question 1.
What is good source of energy?
Answer:
A good source of energy is

  • One which would do a large amount of work per unit volume or mass.
  • which is easily accessible.
  • which is easy to store and transport
  • Perhaps most importantly economical.

Question 2.
What is a good fuel?
Answer:
Bio-gas is an excellent fuel as it contains upto 75% methane.

Question 3.
If you could use any source of energy for heating your food, which one would you use and why?
Answer:
We would use a microwave oven for heating the food as it heats uniformly and clearly without any loss in its nutritional value.

Question 4.
What are the disadvantages of fossil fuels?
Answer:
The oxides of carbon, nitrogen and sulphur that are released on burning fossil fuels are acidic oxides. These lead to acid rain which affects our water and soil resources. In addition to the problem of air pollution, greenhouse effect of gases like carbon dioxide etc. These are the disadvantages of fossilic fuels.

KSEEB Solutions for Class 10 Science Chapter 14 Sources of Energy

Question 5.
Why are we looking at alternate sources of energy?
Answer:
We are looking at alternate source of energy because

  • The fossil fuel reserves in the earth are limited which may get exhausted soon if continued to be used at the current rate.
  • The use of alternate sources of energy will reduce die pressure on fossil fuels making them last for a much longer time.
  • The pollution being caused by the burning of fossil fuels can be avoided try using an alternate source of energy.

Question 6.
How has the traditional use of wind and water energy been modified for our convenience?
Answer:
The traditional use of wind has been modified by using windmills and that of water by constructing hydroelectric power plants.

Question 7.
What kind of mirror – concave, convex or plain would be best suited ‘ for use in solar cooker? Why?
Answer:
Concave mirror. Because it focus the solar rays and achieve a higher temperature.

Question 8.
What are the limitations of the energy that can be obtained from the oceans?
Answer:
The limitations of the energy that can be obtained from die oceans [tidal energy, wave energy and ocean thermal energy]

  • Tidal energy is not likely to be a potential source: of energy in the future because there are very few sites around the world which are suitable for building tidal dams.
  • Wave energy would be a viable proposition. only where waves are very strong.
  • The energy potential from the sea [tidal energy, wave energy and ocean thermal energy] is quite large but efficient commercial exploitation is difficult;

Question 9.
What is geothermal energy?
Answer:
Heat energy from hot molten rocks present inside the earth under certain favourable conditions created by natural process is known as geothermal energy. IT is form of energy is only type of energy which do not use solar energy.

KSEEB Solutions for Class 10 Science Chapter 14 Sources of Energy

Question 10.
What are the advantages of nuclear energy?
Answer:

  1. In a nuclear reactor designed for electric power generation, such nuclear fuel can be part of a self sustaining fission chain reaction that releases energy at a controlled rate.
  2. By nuclear Energy large quantity of electricity can be generated.

Question 11.
Name two energy sources that you ’ would consider to be renewable. Give reason for your choices?
Answer:

  • Wind energy
  • Solar energy

These sources of energy can be used again and again, endlessly. They will never get exhausted.

Question 12.
Give the names of two energy sources that you would consider to be exhaustible. Give reasons for your choices.
Answer:
Fossil fuels such as coal and petroleum are two energy sources that are exhaustible. Because they are only limited reserves. Fossil fuels are non-renewable sources of energy. So we need to conserve them.

KSEEB Class 10 science Sources of Energy Textbook Exercise Questions and Answers

Question 1.
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
Answer:
(b) a cloudy day

KSEEB Solutions for Class 10 Science Chapter 14 Sources of Energy

Question 2.
Which of the following is not an example of a bio-mass energy source?
(a) wood
(b) gobar-gas
(c) nuclear energy
(d) coal
Answer:
(c) nuclear energy

Question 3.
Most of the sources of energy we use represent stored solar energy. Which of the following is not ultimately derived from the Sun’s energy?
(a) geothermal energy
(b) wind energy
(c) fossil fuel
(d) bio-mass
Answer:
(a) geothermal energy

Question 4.
Compare and contrast fossil fuels and the Sun as direct sources of energy.
Answer:

  • The reserves of fossil fuels are limited, i.e., exhaustible whereas solar energy is available in abundance [and that too without cost], i.e., inexhaustible.
  • Fossils fuels cause pollution on burning whereas solar energy is pollution-free.
  • Fossil fuels can provide energy at any required time whereas solar energy becomes unavailable when the sky is covered with clouds.

Question 5.
Compare and contrast bio-mass and hydroelectricity as sources of energy.
Answer:

  • Biomass is a renewable source of energy only if we plant trees in a planned manner which is not the case with hydroelectricity.
  • The energy from biomass can be obtained by using 9 chulha or a gobar gas plant whereas hydroelectricity requires the construction of dams and rivers.
  • Biomass provides pollution-free energy only when converted into biogas whereas hydroelectricity is totally pollution-free.

Question 6.
What are the limitations of extracting energy from
(a) the wind?
(b) waves?
(c) tides?
Answer:
a)

  • It is not available at all times.
  • It requires a very large area of land.
  •  It is not possible to have a windmill everywhere as to run it, the minimum wind speed of 15 km/hr is required (only possible in open areas like the seaside)

b)

  • Wave energy would be a viable proposition only where waves are very strong.
  •  It is costly to set up devices to trap wave energy.

c)

  • Very few sea coasts in the world have suitable sites for the purpose of harnessing tidal energy.
  • The rise and fall of tides happen only twice in a day and is not sufficient to generate electricity continuously.

Question 7.
On what basis would you classify energy sources as
(a) renewable and non-renewable?
(b) exhausted and inexhaustible?
Are options in (a) and (b) the same?
Answer:
We would classify energy sources as (1) Renewable and Non-renewable Renewable sources of energy are inexhaustible whereas non-renewable sources of energy are exhaustible. Thus the options in (1) and (2) are the same.

Question 8.
What are the qualities of an ideal source of energy?
Answer:
An ideal source of energy has the following qualities

  • It gives us more heat per unit mass.
  • It does not pollute the air on burning by giving out smoke or harmful gases.
  • It should be cheap and easily available.
  • It should be easy to handle, safe to transport.

KSEEB Solutions for Class 10 Science Chapter 14 Sources of Energy

Question 9.
What are the advantages and disadvantages of using a solar cooker? Are there places where solar cookers would have limited utility?
Answer:
Advantages of using solar cooker:

  1. No pollution of environment by using solar cooker.
  2.  This device is easy to operate, cheaper and of little maintenance and work quite satisfactorily without the use of any focussing device.

Disadvantages of using solar cooker:

  1. It is easy to see that these devices are useful only at certain times during the day. In this device, cooking is slowly.
  2. For cold places these are inconvenient.

Question 10.
What are the environmental consequences of the increasing demand for energy? What steps would you suggest to reduce energy consumption?
Answer:
Following are the steps we suggest to reduce energy consumption:

  1. We could develop the technology to use the available or known sources of energy more efficiently and a,lso look to new sources of energy.
  2. Fossil fuels are non-renewable sources of energy. So we need to conserve them.
  3. We should encourage bio-gas instead of cutting number of trees in the forest. Biogas is a renewable source of energy.

Multiple Choice Questions:

Question 1.
The main constituent of biogas is
(a) methane
(b) ethane
(c) butane
(d) hydrogen
Answer:
(a) methane

Question 2.
Which one of the following is not a source of energy?
(a) Levers
(b) Muscle power
(c) Water stored at dams
(d) Flowing water
Answer:
(a) Levers

KSEEB Solutions for Class 10 Science Chapter 14 Sources of Energy

Question 3.
The non-renewable source of energy amongst the following
(a) Coal energy
(b) nuclear energy
(c) Wood
(d) wind energy
Answer:
(a) Coal energy

Question 4.
Which one of the plants uses a conventional source of energy?
(a) Thermal power plant
(b) Hydropower plant
(c) Solar panels
(d) windmill form
Answer:
(a) Thermal power plant

Question 5.
Which of the following sources of energy cannot be used as a source of energy on a cloudy day?
(a) geothermal energy
(b) Tidal energy
(c) Nuclear energy
(d) Solar energy
Answer:
(d) Solar energy

Question 6.
The safest source of energy is
(a) fuel energy
(b) nuclear energy
(c) bioenergy
(d) Solar energy
Answer:
(d) Solar energy

Question 7.
Which of the following is not a form of ocean energy?
(a) geothermal energy
(b) ocean thermal energy
(c) Tidal energy
(d) wave energy
Answer:
(a) geothermal energy

KSEEB Solutions for Class 10 Science Chapter 14 Sources of Energy

Question 8.
Which of the following is not a greenhouse gas?
(a) CO2
(b) CH4
(c) SO2
(d) CO
Answer:
(d) CO

Question 9.
The energy is obtained by the nuclear fusion process in
(a) the sun
(b) nuclear reaction
(c) atomic bomb
(d) geosystem
Answer:
(a) the sun

Question 10.
Which of the following Isotopes of uranium is used for nuclear fission?
(a)92U235
(b) 92U237
(c) 92U238
(d)92U239
Answer:
(a)92U235

KSEEB Class 10 Science Sources of Energy Additional Questions and Answers

Question 1.
Differentiate between renewable and Non-renewable sources of energy with one example for each.
Answer:
1) Non-renewable sources: Fossil fuels like coal, petroleum and natural gas are non-renewable energy sources. These are produced over millions of years due to slow changes and under special circumstances. These are not continuous process and further, it is not becoming possible to discover their new deposits with the present rate of their consumption, it is estimated that known deposits of petroleum in our country will be exhausted in another 200 years and that of coal may last for another 250 years.

2) Renewable sources: The energy derived from flowing water, wind, tides, oceans weaves and biogas are renewable sources. These sources can be harnessed into energy. So long as the earth derives its heat and light from the sun over so long as the present solar system exists. Nuclear energy and geothermal energy are also likely to be available for a much longer time. Wood is another renewable source of energy. Though it takes almost 15 years for a tree to mature, this and nuclear energy are also classified as renewable sources.

KSEEB Solutions for Class 10 Science Chapter 14 Sources of Energy

Question 2.
Differentiate between conventional and non-conventional sources of energy.
Answer:
1) Conventional sources of energy: These are the sources of energy that we often been using for a long time. For example, wood and fossil fuels like coal, petroleum have been common sources of heat energy. The energy of flowing water and wind are also used for limited activities.

2) Non-conventional sources of energy: With increasing demand recently energy from sun sea waves and earth is also topped. The energy derived is called non- conventional sources of energy.

Question 3.
What is fuel?
Answer:
Any substances which may be burnt in air to produce heat and light is known as a fuel, for example, wood, coal, kerosene, petrol.

Question 4.
What is fossil fuels?
Answer:
Coal, petroleum and natural gas are example of fossil fuels. These are found in nature due to the decomposition of animals and plants which have remained embedded inside earth’s crust due to geological changes over millions of years.

Question 5.
Explain why fossil fuels are classified as non renewable sources of energy?
Answer:
Fossil fuels are obtained from the buried plants and animals under earth over millions of years. This phenomena happened due to slow changes in earth process. Thus chances of reoccuring of such processes is very rare and after the present stock is exhausted we cannot hope to get new stocks unless they are drastic changes in the earth process. So fossil fuels are classified as non- i renewable sources.

Question 6.
What are the two disadvantages of burning fossil fuels?
Answer:

  • Burning of coal and petroleum lead to air pollution.
  • Burning of fossils fuels causes smog which causes breathing problems and other hazards.

Question 7.
List any two steps you would suggest minimizing environmental pollution caused by the burning of fossil fuels.
Answer:

  • The evolution of poisonous gases can be reduced by use of efficient combustion processes and techniques.
  • Ashes etc should be properly discarded.

KSEEB Solutions for Class 10 Science Chapter 14 Sources of Energy

Question 8.
The use of dry wood as domestic fuel is not considered as good fuel. State two reasons?
Answer:

  • Wood has low efficiency.
  • On burning wood leaves lot of reduce and gases are produced to cause environment pollution.

Question 9.
What are the two ways in which animal dung can be utilised as a fuel?
Answer:

  • To heat animal dung in the form of cakes.
  • A naerobic degradation of animal dung to produce useful fuel is called bio-gas.

Question 10.
Why is charcoal considered to be a better fuel than wood?
Answer:

  • bums without flame.
  • is comparatively smokeless.
  • has higher heat generation efficiency

Question 11.
List two nutrients that the slurry left behind in the bio gas plant contains?
Answer:
Nitrogen and phosphorous

Question 12.
What kind of energy transformation take place at a?
(1) Hydroelectric powerhouse
(2) Thermal power
Answer:

  • Hydroelectric powerhouse: At a hydroelectric powerhouse the potential energy of water is first converted into kinetic energy which is then converted into electrical energy.
  • Thermal power station: At a thermal power the chemical energy of coal or other fuels is converted into heat energy which is further changed into electrical energy.

Question 13.
What is the important limitation of water and wind energy?
Answer:
Flowing water and wind are not found everywhere and in plenty. Therefore such energy has usefulness only at a such places where their flow is in plenty.