Objective

Question-2. Name the different sources of energy.

Ans- Water, Air, Coal, Petroleum, Natural Gas etc.

Question-3. By what process do green plants make their food in the presence of the sun?

Ans- by photosynthesis

Question-4. What is the calorific value of a good fuel?

Ans- high

Question-5. How many types of energy sources are there?

Ans- two

1. (renewable and non-renewable sources)

2. (Traditional and Non-Traditional Sources)

Question-6. The sources of energy that can never be exhausted are called which sources of energy?

Ans- renewable sources

Question-7. Which energy source is available in unlimited quantities in nature?

Ans- renewable energy sources

Question-8. Give examples of renewable energy sources.

Ans- Solar Energy, Wind Energy, Hydroelectric Energy, Geothermal Energy, Ocean Energy

Question-9. The sources of energy that can be exhausted at any time in nature are called which sources of energy?

Ans- non-renewable source

Question-10. Give examples of non-renewable energy sources.

Ans- petroleum, coal, etc.

Question-11. The sources of energy which are widely used and supply the majority of the energy are called what?

Ans- conventional energy sources

Question-12. Give examples of conventional energy sources.

Ans- fossil fuels, wind energy, biomass energy

Question-13. What are the sources of energy that are not widely used and only a limited amount of energy is supplied?

Ans- non-conventional energy sources

Question-14. Give examples of non-conventional energy sources.

Ans- Solar Energy, Wave Energy, Geothermal Energy, Ocean Thermal Energy, Nuclear Energy

Question-15. The remains of plants and animals buried inside the earth for millions of years were converted into fuels due to high temperature and pressure in the absence of oxygen. What is such a fuel called?

Ans- fossil fuel

Question-16. Give examples of fossil fuels.

Ans- coal, petroleum, natural gas

Question-17. What is a fuel containing a mixture of free carbon and complex compounds of carbon called?

Ans- Coal

Question-18. How many types of coal are there?

Ans- 4 (peat, lignite, bituminous, anthracite)

Question-19. Which is the best quality coal?

Ans- anthracite

Question-20. What is present in coal besides carbon?

Ans- Oxygen, Nitrogen and Sulfur

Question-21. Where are the huge deposits of coal in India?

Ans- Jharkhand, West Bengal, Orissa and Madhya Pradesh

Question-22. What happens when coal is burnt?

Ans- Carbon-di-oxide (CO₂) and carbon monoxide (CO)

Question-23. What kind of gas is carbon monoxide (CO)?

Ans- poisonous

Question-24. What is a plant that generates electricity called?

Ans- thermal power plant

Question-25. Petroleum is a mixture of

Ans- of natural hydrocarbons

Question-26. The method by which crude oil is divided into pure fractions is called

Ans- refining of petroleum

Question-27. Which method is used for refining petroleum?

Ans- Fraction Distillation Method

Question-28. Petroleum gas is a mixture of?

Ans- ethane, propane and butane

Question-29. What is the main component of petroleum gas?

Ans- Butane (C₄H₁₀)

Question-30. Liquefied petroleum gas is a mixture of

Ans- normal butane and isobutane

Question-31. What is Natural Gas?

Ans- fossil fuel

Question-32. Natural gas is a mixture of

Ans- of methane, ethane and propane

Question-33. What is the main component of natural gas?

Ans- Methane (CH₄)

Question-34. What is the full form of CNG?

Ans- Compressed Natural Gas

Question-35. Compressed natural gas (CNG) is used.

Ans- as fuels in vehicles

Question-36. Compressed natural gas (CNG) comes from.

Ans- less pollution

Question-37. What produces carbon-di-oxide (CO₂), which is a danger indicator.

Ans- green house effect

Question-38. What is sulfur dioxide responsible for?

Ans- acid rain

Question-39. What is the energy in running water?

Ans- kinetic energy

Question-40. What causes the water to move rapidly in a hydroelectric plant?

Ans- by turbine

Question-41. Is hydroelectric energy?

Ans- pollution free

Question-42. What is the organic matter contained in the body of plants and animals called?

Ans- biomass or biomass

Question-43. When wood is burnt in the presence of limited air, the water and volatile substances present in it come out and the dark black residue left is called?

Ans- Charcoal (charcoal)

Question-44. There is charcoal compared to wood.

Ans- good fuel

Question-45. Which gas is released when plants and animals decompose in the absence of residual oxygen?

Ans- biogas

Question-46. What is the main component of biogas?

Ans- Methane (CH₄)

Question-47. The plant by which biogas is generated is called?

Ans- biogas plant

Question-48. What is a device that converts wind energy into mechanical energy or electrical energy called?

Ans- Wind mill

Question-49. Which country has the first place in generating electricity by wind energy?

Ans- Denmark

Question-50. What is the rank of India in the production of electricity by wind energy?

Ans- fifth

Question-51. Which is called the land of winds?

Ans- Denmark

Question-52. Where is the largest wind power farm in India?

Ans- In Tamil Nadu (near Kanyakumari)

Question-53. What is the source of wind energy?

Ans- renewable sources

Question-54. How much electrical power is produced by wind power in our country?

Ans- 1030 MW

Question-55. What should be the minimum wind speed to generate electricity by wind energy?

Ans- 15 km/h

Question-56. What is the energy released from the sun called?

Ans- solar energy

Question-57. How do solar cookers get energy?

Ans- from solar power (by sunlight)

Question-58. How many types of solar cookers are there?

Ans- two

Question-59. Which mirror is installed in a solar cooker?

Ans- concave mirror

Question-60. When a solar furnace is used to generate electricity, what is it called?

Ans- solar power tower

Question-61. What is a device that converts solar energy into electrical energy called?

Ans- solar cell

Question-62. What is used to make solar cells?

Ans- semiconductors (silicon and germanium)

Question-63. Solar cells are used.

Ans- In calculators, wristwatches, electric bulbs and toys

Question-64. Which wire is used in solar cell?

Ans- silver wire

Question-65. In how many forms is the energy obtained from the ocean found?

Ans- 3 (Tidal Energy, Wave Energy, Ocean Thermal Energy)

Question-66. Tidal energy, wave energy and ocean thermal energy are the sources of which energy?

Ans- renewable sources

Question-67. What is the heat energy stored in the hot spots of the earth's crust called?

Ans- geothermal energy

Question-68. When the nucleus of an atom is bombarded with particles like a metron, then that nucleus splits and releases a large amount of energy, then what is this energy called?

Ans- nuclear energy (nuclear energy)

Question-69. What is the use of nuclear energy (nuclear energy)?

Ans- in power generation, space research and war

Question-70. Who discovered nuclear reaction first?

Ans- Rutherford (in 1919)

Question-71. Such a nuclear reaction in which two lighter nuclei combine to form one heavy and one stable nucleus, what is this reaction called?

Ans- nuclear fusion

Question-72. Nuclear fusion is induced by?

Ans- by proton

Question-73. Nuclear fission is induced by?

Ans- by neutron

Question-74. The plant in which electrical energy is obtained by converting nuclear energy into heat energy, then what is it called?

Ans- nuclear reactor or nuclear reactor

Question-75. What is the SI unit of energy?

Ans- joule

Question-76. What energy does a hydroelectric plant convert into electrical energy?

Ans- to nuclear energy

Question-77. A good fuel should have a calorific value.

Ans- high

Question-78. What is the main source of energy on earth in nature?

Ans- Sun (solar energy)

Question-79. What are the real sources of energy from fossil fuels?

Ans- Sun

Question-80. Solar hydro-heater cannot be used for drinking hot water.

Ans- on cloudy days

Question-81. Which fuel is used to get energy from nuclear fusion?

Ans- of hydrogen gas

Question-82. Which material is used to make solar cells?

Ans- silicone

Question-83. The utensils used in solar cookers are usually painted with which color?

Ans- with black

Question-84. What is a thick solution of cow dung and water called?

Ans- Kardam

Question-85. Solar panels are combined in large quantities.

Ans- solar cell

Question-86. Which gas is emitted in ideal fuel?

(a) methane (b) oxygen (c) carbon-di-oxide (d) none of these

Ans- (d) none of these

Question-87. The value of energy obtained by fission of one atom of ²³⁵₉₂U is—

Ans- 931 MeV

Question-88. Which of the following is the best source of energy?

(a) Wood (b) Coal (c) Petroleum (d) Biomass

Ans- (d) Biomass