Advertisements
Advertisements
प्रश्न
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.
Advertisements
उत्तर
About 300 million years ago, the earth had dense forests in low lying wetland areas. Due to natural processes like floods, these forests got buried under the soil. As more soil deposited over them, they were compressed. The temperature also rose as they sank deeper and deeper. Under high pressure and high temperature, dead plants got slowly converted into coal.
APPEARS IN
संबंधित प्रश्न
Why is LPG considered a better fuel than coal?
Why is the leakage of LPG detected easily although it is odourless? State the steps to be taken in case its leakage is detected in the kitchen.
Fossil fuels are energy rich compounds of an element X which were originally made by the plants with help of sun's energy.
Name another element which is usually found in combination with X in fossil fuels.
The energy in petrol originally came from the sun. Explain how it got into petrol.
The major component of biogas is:
(a) hydrogen
(b) butane
(c) hydrogen sulphide
(d) methane
A certain form of energy is available due to the difference in the temperature of water at the surface of the ocean and its deeper levels.
(a) Name the form of energy.
(b) Is this energy ultimately derived from the sun or not?
(c) Explain how this form of energy can be converted into electricity.
(d) What is the minimum temperature difference in water at the surface of ocean and its deeper level which is required to operate power plants based on is energy?
Which of the following is ultimately not derived from the sun's energy (or solar energy)?
(a) wind energy
(b) nuclear energy
(c) biomass energy
(d) ocean thermal energy
State whether the following is True or False.
The Sardar Sarovar Dam is built on the river Narmada.
What are fossil fuels?
Complete the crossword in figure with the help of the clues:
Across
1. Fuels obtained from dead remains of living organisms. (6, 5)
2. A process by which the various constituents of petroleum are separated. (8)
3. A porous black substance obtained from coal. (4)
4. Another name for motor fuel. (6)
Down
5. The substance obtained by carbonisation. (4)
6. Fuel for heavy motor vehicles. (6)
7. A petroleum product used for road surfacing. (7)
8. Dead remains of sea animals got converted into it. (9)
