NCERT Solutions for Class 7 Geography Chapter 2 Inside Our Earth

NCERT Solutions for Class 7 Geography Chapter 2 Inside Our Earth Social Science

NCERT Solutions for Class 7 Geography Chapter 2 Inside Our Earth is provided on this page will enable you to come up with methods and strategies that will aid in total focus. Whether it is to prepare for an upcoming exam or to simply learn more the key is reviewing the basics. Thus, we offer full NCERT Solutions so you can focus on understanding how each concept manages to fit together. This will be a beneficial tool because it can be used to recall various questions at any time.

Chapter 2 Inside Our Earth NCERT Solutions for Class 7 Geography

1. Answer the following questions

(i) What are the three layers of the earth?

Solution

The three layers of earth are:

• Crust

• Mantle

• Core

(ii) What is a rock?

Solution

Any natural mass of solid mineral matter that makes up the Earth’s crust is called a rock.

(iii) Name three types of rocks.

Solution

The three types of rocks are:

• Igneous Rocks

• Sedimentary Rocks

• Metamorphic Rocks

(iv) How are extrusive and intrusive rocks formed? 

Solution

Extrusive rocks are formed by the molten lava which comes on the earth's surface and rapidly cools down to becomes solid.  For example, Basalt.

When the molten magma cools down deep inside the earth's crust then the solid rocks so formed are called intrusive rocks. For example, Granite.

(v) What do you mean by a rock cycle?

Solution

The process of transformation of rocks from one type to another through changes in certain conditions is called a rock cycle.

(vi) What are the uses of rocks? 

Solution

Rocks are useful for various purposes:

• It helps in making roads

• It is used in the construction of houses and buildings

• Some rocks are shiny and precious therefore used for making jewellery.

• Soft rocks are used for making talcum powder, chalks etc.

(vii) What are metamorphic rocks?

Solution

The rocks which are formed due to conversion of igneous and sedimentary rocks under great heat and pressure is called metamorphic rocks.

2. Tick the correct answer. 

(i) The rock which is made up of molten magma is

(a) Igneous

(b) Sedimentary

(c) Metamorphic

Solution (a) Igneous

(ii) The innermost layer of the earth is

(a) Crust

(b) Core

(c) Mantle

Solution (b) Core

(iii) Gold, petroleum and coal are examples of 

(a) Rocks

(b) Minerals

(c) Fossils

Solution (b) Minerals

(iv) Rocks which contain fossils are

(a) Sedimentary rocks

(b) Metamorphic rocks

(c) Igneous rocks

Solution (a) Sedimentary rocks

(v) The thinnest layer of the earth is

(a) Crust

(b) Mantle

(c) Core

Solution (a) Crust

3. Match the following.

(i) Core	(a) Earth's surface
(ii) Minerals	(b) Used for roads and buildings
(iii) Rocks	(c) Made of silicon and alumina
(iv) Clay	(d) Has definite chemical composition
(v) Sial	(e) Innermost layer
	(f) Changes into slate
	(g) Process of transformation of the rock

Solution

(i) Core	(e) Innermost layer
(ii) Minerals	(d) Has definite chemical composition
(iii) Rocks	(b) Used for roads and buildings
(iv) Clay	(f) Changes into slate
(v) Sial	(c) Made of silicon and alumina

4. Give reasons. 

(i) We cannot go to the centre of the earth.

Solution

We cannot go to the centre of the earth because the it has very high temperature and pressure and lies 6000 km below the ocean floor. We will not able to survive there because there is no oxygen or favourable conditions. 

(ii) Sedimentary rocks are formed from sediments.

Solution

Sedimentary rocks are formed from sediments because of extreme compression and hardening of the particles of sediment which are transported and deposited by wind, water etc.

(iii) Limestone is changed into marble.

Solution

Limestone is changed into marble because of extreme heat and pressure as it is a sedimentary rock.