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
Classify the following
Coal, Wind, Tides, Petroleum,Wood, Natural gas
What is the basis of above classification?
What are the disadvantages of burning fossil fuels?
The natural gas consists mainly of:
(a) methane
(b) ethane
(c) propane
(d) butane
Name the major component of biogas.
Select the renewable and non-renewable sources of energy from the following :
- Coal
- Wood
- Water
- Diesel
- Wind
- Oil
Write a short note on nuclear power.
Can you tell?
What are the non-conventional energy resources?
Explain why is it no wise to regard wood as a renewable sources of energy.
Match the items given in Column I with the items of Column II.
| Column I | Column II |
| (a) Used for road surfacing | (i) Black gold |
| (b) Natural gas | (ii) Vaseline and candles |
| (c) Petroleum | (iii) Bitumen |
| (d) Paraffin wax | (iv) CNG |
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)
