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प्रश्न
What are fossil fuels?
उत्तर
Fuels formed in the geological past from the remains of living organisms and plants etc. Examples of fossil fuels are coal, petroleum, and natural gas, etc.
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संबंधित प्रश्न
Define ignition temperature of a fuel.
Name two sources of energy that you think are renewable. Give reason for your choice.
Most of the fuels contain carbon as one of the constituents. Name a fuel which has very high calorific value but not contain carbon.
State one important use of CNG these days.
Why is LPG considered a good fuel?
Describe how fossil fuels were formed.
Which fossil fuels were formed by the buried remains of small plants and animals?
The natural gas consists mainly of:
(a) methane
(b) ethane
(c) propane
(d) butane
State whether the following statement is true or false:
Tidal energy is one of the forms in which solar energy manifests itself in oceans.
What are the two ways in which cow-dung can be used as a fuel? Which of them is better and why?
Suggest a safe and efficient method for the disposal of biowastes and sewage materials. How is this method advantageous to us?
Most of the sources of energy that we sue represent stored solar energy. Which of the following is not ultimately derived from the sun's energy?
(a) wind energy
(b) geothermal energy
(c) fossil fuels
(d) biomass
One of the following is not required in the formation of biogas in a biogas plant. This is:
(a) cow-dung
(b) water
(c) oxygen
(d) anaerobic bacteria
What type of nuclear reaction is responsible for the liberation of energy:
in a nuclear reactor?
Which produced of the nuclear fission of uranium-235 is utilised to cause further fission of its nuclei?
Higher Order Thinking Skill (HOT)
What are the objectives for replacing non-conventional energy resources from conventional energy resources?
Why is there a need to harness non-conventional sources of energy? Give two main reasons.
What are the environmental consequences of using fossil fuels? Suggest the steps to minimise the pollution caused by various sources of energy including non-conventional sources of energy.
Some natural resources are given below. Classify them into the exhaustible and inexhaustible natural resources.
| Air | coal | natural gas | sunlight | petroleum | minerals | forests | oxygen |
Fill in the blanks and complete the story.
About 300 million years ago, the earth had dense ______ in low lying wetland areas. Due to natural processes like ______ these forests got buried under the ______ As more ______ deposited over them, they were compressed. The ______ also rose as they sank deeper and deeper. Under high ______ and high ______ , dead plants got slowly converted into coal.
