Class 7 Geography Chapter 2 Practice Question Answers - Inside Our Earth

Q1. The Deccan plateau is made up of:
(a) Clay
(b) Granite
(c) Basalt
(d) None of the above
Ans: (c)

Q2. The depth of deepest mine in South Africa is about:
(a) 3km
(b) 4km
(c) 5 km
(d) 6 km
Ans: (b)

Q3. The innermost layer is the core is made of:
(a) Nickel and Iron
(b) Silica and Alumina
(c) Silica and magnesium
(d) a and b both
Ans: (a)

Q4. What is meaning of igneous?
(a) Air
(b) Water
(c) Lime
(d) Fire
Ans: (d)

Q5. The radius of the earth is:
(a) 6000 km
(b) 6300 km
(c) 6371 km
(d) 6400 km
Ans: (c)

Q6. Igneous and sedimentary rocks can change into:
(a) Intrusive igneous rocks
(b) Extrusive igneous rocks
(c) Metamorphic rocks
(d) Igneous rocks
Ans: (c)

Q7. Depth of mantle layer of the earth is:
(a) 2900 km
(b) 3000 km
(c) 3100km
(d) 3200 km
Ans: (a)

Q8. In search for oil engineers have dug a hole about:
(a) 3km
(b) 4km
(c) 5 km
(d) 6 km
Ans: (d)

Q9. Igneous rocks are made when:
(a) The solid magma melts and it becomes solid
(b) The cool magma molten, it becomes solid
(c) The molten magma cools, it becomes solid
(d) Solid magma molten, it becomes solid
Ans: (c)

Q10. Igneous rocks are called primary rocks because:
(а) All the other rocks are formed from the igneous rocks.
(b) These are important for human beings.
(c) These rocks produce all the ailments.
(d) None of the above.
Ans: (а)

Q11. Gold, Petroleum and Coal are the examples of what?
(a) Rock
(b) Fossils
(c) Minerals
(d) Core
Ans: (b)
The remains of the dead plants and animals trapped in the layers of rocks are called fossils. Gold, Petroleum and Coal are the examples of these fossils.

Q12. What is the Radius of the earth?
(a) 2600 km
(b) 3671km
(c) 7163 km
(d) 6371 km
Ans: (d)
The radius of the earth is 6371 km.

Q13. What is the Innermost layer of the earth?
(a) Crust
(b) Mantle
(c) Core
(d) None of these
Ans: (c)
The innermost layer is the core with a radius of about 3500 km. The central core has very high temperature and pressure.

Q14. Which rocks are known as primary rocks?
(a) Igneous rocks
(b) Sedimentary rocks
(c) Metamorphic rocks
(d) None of these
Ans: (a)
When the molten magma cools, it becomes soli(d) Rocks thus formed are called igneous rocks. They are also called primary rocks.

Q15. Where is the deepest mine in the world located?
(a) South America
(b) South Africa
(c) South Australia
(d) South India
Ans: (b)
The deepest mine in the world, is in South Afric(a) It is about 4 km. deep. In search for oil engineers have dug a hole about 6 km. deep.

Q16. What is the percentage of the volume of the earth?
(a) 1
(b) 15
(c) 89
(d) 20
Ans: (a)
The crust forms only 1 per cent of the volume of the earth, 84 per cent consists of the mantle and 15 per cent makes the core.

Q17. What are the uses of rocks?
(a) Building materials
(b) As a source of metals
(c) Both a and b
(d) None of these
Ans: (c)
Rocks are useful in many ways as building materials and as a source of metals like iron, copper etc. and fossil fuels. They also yield valuable gems such as diamonds, garnet, jade etc.

Q18. Why earth is called a dynamic planet?
(a) Continuously undergoes changes
(b) Never change
(c) Is very large in size
(d) None of these
Ans: (a)
Earth is called a dynamic planet because it continuously undergoes changes inside and outside.

Q19. What is a rock?
(a) Natural mass of mineral
(b) Artificial mass
(c) Both a and b
(d) None of these
Ans: (a)
A rock is a natural mass of mineral matter that makes up the earth’s crust.

Q20. What are the layers of the earth?
(a) Crust
(b) Mantle
(c) Core
(d) All of the above
Ans: (d)
Three layers of the earth are crust, mantle and core.