Inside Our Earth

Q1. Fill in the blanks.

                        i.        Igneous rocks are also called primary rocks.

                       ii.        Gold, petroleum and coal are examples of minerals.

                      iii.        The thinnest layer of the earth is crust.

                      iv.        Deccan plateau is made up of basalt rocks.

                      v.        The Taj Mahal is made of white marble.

Q2. True/False

                        i.        There are two types of igneous rocks: intrusive rocks and extrusive rocks. True

                      ii.        Rocks which contain fossils are metamorphic rocks. False

                     iii.        Clay changes into slate and limestone into marble. True

                     iv.        It is constantly undergoing changes inside and outside. True

                      v.        Grinding stones used to prepare paste/powder of spices and grains are made of sedimentary rock. False

                     vi.        The earth, our homeland is a dynamic planet. True

Q3. Give an example of extrusive igneous rocks.

Ans. Basalt

Q4. What is the radius of earth?

Ans. The radius of the earth is 6371 km.

Q5. What is the core of the earth made up of?

Ans. It is mainly made up of nickel and iron.

Q6. What is the innermost layer of the earth?

Ans. The innermost layer of the earth is the core.

Q7. Name the monument which is made of red sandstone?

Ans. The Red Fort is made of red sandstone.

Q8. What are the three layers of the earth?

Ans. The three layers of the earth are crust, mantle and core.

Q9. What is crust?

Ans. The uppermost layer over the earth’s surface is called the crust.

Q10. What is the uppermost layer of the Earth called?

Ans. The uppermost layer of the Earth is called crust.

Q11. What is the Latin word for igneous?

Ans. Latin word for igneous is Ignis meaning fire.

Q12. What is the Latin word for sedimentary?

Ans. Latin word for sedimentary is sedimentum which means settle down.

Q13. What is the Greek word for metamorphic?

Ans. Greek word for metamorphic is metamorphose meaning change of form.

Q14. What are the main mineral constituents of the continental mass?

Ans. The main mineral constituents of the continental mass are silica and alumina.

Q15. What is a rock?

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

Q16. Name three types of rocks.

Ans. There are three major types of rocks: igneous rocks, sedimentary rocks and metamorphic rocks.

Q17. How much of the earth is crust, mantle and core?

Ans. 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.

Q18. What makes up the crust of the earth?

Ans. The earth’s crust is made up of various types of rocks such as igneous, metamorphic, and sedimentary rocks.

Q19. What are fossils?

Ans. The remains of the dead plants and animals trapped in the layers of rocks are called fossils.

Q20. What are metamorphic rocks?

Ans. When the igneous and sedimentary rocks are subjected to heat and pressure they change into metamorphic rocks.