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Q.1. The three layers of the earth are ________, ________ and ________.
Core, Crust, Mantle
Q.2. ________ are used in making Jewellery.
Q.3. ________ is formed from shells.
Q.4. ________ rock is the transformation of a certain type of rock into another type of rock.
Q.5. ________ is formed from old decayed plants.
Q.6. The bottom layer of soil is called ________.
Q.7. Rock used by dentist to polish teeth
Q.8. The rock formed when pebbles and gravel get cemented together:
Q.9. Rock used in making cement:
Q.10. Rock formed from granite which has got different types of stripes.
Q.11. Non – Metallic Mineral formed from dead plants and animals.
Q.12. How is petroleum used in gaseous form? Mention any two uses of petroleum.
Petroleum is used in gaseous form as CNG (Compact Natural Gas).
Two uses of Petroleum:
(i) Petroleum is used for making petrol
(ii) It is used for create Diesel.
Q.13. Why should we use our resources judiciously? Mention two ways in which we can use our resources carefully?
This is because, Minerals take thousands of years to be made. It cannot be produced by man so it is imperative for us.
Two ways in which we can use our resources carefully:
(i) Keeping the vehicles in good condition so that they use less fuel.
(ii) adopt more ways to use solar or wind energy.
Q.14. How is an igneous rock formed?
The core is the innermost layer of earth and is made of molten lava which is a hot liquid. When this liquid lava flows out on the surface of the earth and cools down it become solid rock. This solid rock is called igneous rock.
Q.15. How are metamorphic rocks forms?
It is formed wither by intense heating up or squashing of the earth’s crust.
Q.16. What is soil erosion?
The wearing away of soil from the earth surface by wind or water called Soil erosion.
Q.17. What is soil? Mention the three types of soil.
The uppermost layer of the Earth that supports life and provides food for all is called soil.
The three types of soil are: Sandy soil, Clayey soil and Loamy soil.
Q.18. How is coal formed? Mention three uses of coal.
Coal is formed when forests are buries underground, due to heat and pressure. They change into a dark substance formed coal.
Uses of Coal:
(i) Man using coal in his iron.
(ii) Coal is used for electricity generation in thermal power plant.
(iii) Coal is used for cooking.
Q.19. Explain the three layers of soil.
The three layers of soil are: Bedrock, Subsoil & Topsoil.
Bedrock: At the bottom are the big pieces of rocks are called bed rock.
Subsoil: The soil above the bedrock called subsoil. Which has minerals and some amount of brownish black material formed when plants and animals decay called humus.
Topsoil: The topmost layer is called top soil.