Interior Of Earth 7th Social Science Lesson 3 Questions in English

7th Social Science Lesson 3 Questions in English

3. Interior Of Earth

1) On the basis of the study of earthquake waves the spherical earth is found to be ________ concentric Layers

a) 2

b) 3

c) 4

d) 6

Explanation: On the basis of the study of earthquake waves the spherical earth is found to be three concentric layers.

2) Which is the outermost layer of the earth?

a) Sigma

b) Core

c) Crust

d) Mantle

Explanation: The crust is the outermost layer of the earth.

3) The thickness of Crust Varies from

a) 5-15 km

b) 5-30 km

c) 10-20 km

d) 10-30 km

Explanation: The crust is the outermost layer of the earth. Its average thickness varies from 5 to 30 km

4) How much Km is of Crust of Ocean floors?

a) 5 km

b) 10 km

c) 15 km

d) 30 km

Explanation: It is about 35 km on the continental masses and only 5 km on the ocean floors.

5) The continental crust is _____ dense than the oceanic crust because it is made of both light and dense rock types.

a) More

b) Less

c) Equal

d) None of above

Explanation: The continental crust is less dense than the oceanic crust because it is made of both light and dense rock types.

6) The oceanic crust is composed mostly of dense rocks such as

a) Sigma

b) Basalt

c) Lime

d) Gabbro

Explanation: The oceanic crust is composed mostly of dense rocks such as basalt.

7) Earth is called as blue Planet because _____% of the earth is covered by water

a) 68

b) 69

c) 71

d) 73

Explanation: Earth is called as blue Planet. 71% of the earth is covered by water.

8) The upper part of crust consists of granite rocks and forms the continents called

a) Sigma

b) Sial

c) Core

d) Basalt

Explanation: The upper part consists of granite rocks and forms the continents. It has the main mineral constituents are silica and alumina. So it is collectively referred to as Sial.

9) The average density of Sial is

a) 2.1 g/cm^3

b) 2.5 g/cm^3

c) 2.7 g/cm^3

d) 3 g/cm^3

Explanation: It has an average density of 2.7g/cm3.

10) The lower part of crust is a continuous zone of denser basaltic rocks forming the ocean floors called

a) Sima

b) Sial

c) Mantle

d) Core

Explanation: The lower part is a continuous zone of denser basaltic rocks forming the ocean floors, comprising mainly of silica and magnesium. It is therefore called Sima.

11) The Sima has a average density of

a) 2.1 g/cm³

b) 2.5 g/cm³

c) 2.7 g/cm³

d) 3 g/cm³

Explanation: The lower part is a continuous zone of denser basaltic rocks forming the ocean floors, comprising mainly of silica and magnesium. It is therefore called Sima. It has an average density of 3.0g/cm3.

12) The next layer beneath the crust is called the

a) Core

b) Sigma

c) Mantle

d) Crust Rock

Explanation: The next layer beneath the crust is called the mantle

13) Mantle is separated from the crust by a boundary called

a) Lithosphere plates

b) Basalt rocks

c) Mohorovicic discontinuity

d) None of above

Explanation: The next layer beneath the crust is called the mantle. It is separated from the crust by a boundary called Mohorovicic discontinuity.

14) Which of following is False

a) The mantle is about 2,900 km thick.

b) The upper mantle with a density of 3.4 – 4.4g/cm3. extends down to 700 km

c) The lower mantle having a density of 4.4– 5.5g/cm3 extends from 700 to 2000 km

d) All are False

Explanation: The mantle is about 2,900 km thick. It is divided into two parts. (i) The upper mantle with a density of 3.4 – 4.4g/cm3. extends down to 700 km. (ii) The lower mantle having a density of 4.4– 5.5g/cm3 extends from 700 to 2,900 km.

15) The innermost layer of the earth is called the core. It is also known as

a) Barysphere

b) Lithosphere

c) Garyosphere

d) Cores

Explanation: The innermost layer of the earth is called the core. It is also known as Barysphere.

16) Core is Separated from mantle by

a) Mohorovicic discontinuity

b) Weichart-Gutenberg discontinuity

c) Aestenosphere

d) None

Explanation: It is separated from the mantle by a boundary called Weichart-Gutenberg discontinuity.

17) The inner core, composed of ______and ______ which is solid in state.

a) Copper and Ferrous

b) Nickel and Ferrous

c) Zinc and Copper

d) Ferrous and Zinc

Explanation: The inner core, composed of Nickel and Ferrous (Nife), is solid in state.

18) The average density of core is

a) 13 g/cm³

b) 10 g/cm³

c) 15 g/cm³

d) 23 g/cm³

Explanation: The average density of core is 13.0 g/cm3.

19) The crust forms only 1 per cent of the volume of the earth, _____ % consists of the mantle and ____ makes the core.

a) 84 and 15

b) 75 and 24

c) 90 and 9

d) 23 and 76

Explanation: The crust forms only 1 per cent of the volume of the earth, 84 % consists of the mantle and 15 % makes the core.

20) The radius of the earth is

a) 6200 km

b) 6371 km

c) 5431 km

d) 7254 km

Explanation: The radius of the earth is 6371 km.

21) The outer core, which is rich in _____ is in liquid state

a) Iron

b) Chromium

c) Phosphorous

d) Nickel

Explanation: The outer core, which is rich in iron, is in liquid state. It extends between 2,900 – 5,150 km.

22) The lithosphere is broken into a number of plates known as the

a) Earth plates

b) Tectonic Plates

c) Wave plates

d) Lithospheric Plates

Explanation: The lithosphere is broken into a number of plates known as the Lithospheric plates.

23) The movement of the Earth’s lithospheric plates is termed as

a) Plate Movement

b) Tectonic movements

c) Plate waves

d) Lithosphere movement

Explanation: The movement of the Earth’s lithospheric plates is termed as tectonic movements. The energy required to move these plates is produced by the internal heat of the earth.

24) Which is the is the part of the mantle that flows and moves the plates of the earth?

a) Lithosphere

b) Barysphere

c) Aesthenosphere

d) Garyosphere

Explanation: Asthenosphere – The asthenosphere is the part of the mantle that flows and moves the plates of the earth.

25) When an oceanic plate collides with a continental plate, the denser oceanic plate is forced _____ the continental plate

a) Above

b) Below

c) To Collide

d) None

Explanation: When an oceanic plate collides with a continental plate, the denser oceanic plate is forced below the continental plate. As a result of the pressure from above the rocks heats up and melt. The molten rocks rise again forming volcanic mountains along the continental edge.

26) The forces which act in the interior of the earth are called as

a) Exogenic Forces

b) Endogenic forces

c) Gravitational Forces

d) Balanced Forces

Explanation: The forces which act in the interior of the earth are called as Endogenic forces and the forces that work on the surface of the earth are called as Exogenic forces.

27) A sudden movement of a portion of the earth’s crust which produces a shaking or trembling is known as an

a) Tremor

b) Earthquake

c) Richter

d) None of above

Explanation: A sudden movement of a portion of the earth’s crust which produces a shaking or trembling is known as an earthquake

28) From the focus, the earthquake vibrations travel in different directions in the form of

a) Plates

b) Seismic Plates

c) Seismic Waves

d) Tremors

Explanation: From the focus, the earthquake vibrations travel in different directions in the form of seismic waves.

29) The point where these vibrations originate is called the

a) Epicenter

b) Centroid

c) Focus

d) Core

Explanation: The point where these vibrations originate is called the focus of the earthquake. The point of the earth’s surface directly above the focus is called the epicenter of the earthquake.

30) The earthquake waves are recorded by an instrument known as

a) Quake meter

b) Richter scale

c) Seismograph

d) Altimeter

Explanation: The earthquake waves are recorded by an instrument known as seismograph.

31) The magnitude of an earthquake is measured by the

a) Seismometer

b) Richter scale

c) Tremor scale

d) Gyroscope

Explanation: The magnitude of an earthquake is measured by the Richter scale

32) The numbers on this scale range from 0 to

a) 11

b) 9

c) 10

d) 13

Explanation: The numbers on this scale range from 0 to 9

33) Magnitude of ____ on Richter scale is classified as a major earthquake

a) 7

b) 6

c) 5

d) 6.5

Explanation: An earthquake over 5.0 on Richter scale can cause damage from things falling. A 6.0 on Richter scale or higher magnitude is considered very strong and 7.0 on Richter scale is classified as a major earthquake.

34) Tsunami_________, is the name given to the huge wave caused in the sea by an earthquake

a) Indonesian Term

b) Japanese Term

c) Indian Term

d) Latin Term

Explanation: Tsunami, a Japanese term, is the name given to the huge wave caused in the sea by an earthquake. Tsunamis are quite common along the coasts of Japan and other regions in the Pacific Ocean.

35) Tsunami in the Indian Ocean swept coastal area of Indonesia, India, Srilanka, Thailand on

a) 26th Dec 2004

b) 26th Nov 2004

c) 26th Dec 2005

d) 26th Nov 2005

Explanation: On 26th Dec 2004 Tsunami in the Indian Ocean swept coastal area of Indonesia, India, Sri Lanka, Thailand etc., They caused immense damage to life and property in the coastal area.

36) How many percent of of earthquakes occur in Pacific ring of fire belt?

a) 68

b) 70

c) 72

d) 61

Explanation: The world’s distribution of earthquakes coincide very closely with that of volcanoes. Regions of greatest seismicity are circum-Pacific areas, with the epicenters and the most frequent occurrences along the Pacific Ring of Fire. It is said that about 68 percent of earthquakes occur in this belt.

37) In India, the Himalayan region and the ________ valley are prone to earthquake

a) Siwalik

b) Narmada

c) Ganga-Brahmaputra

d) None of above

Explanation: India, the Himalayan region and the Ganga-Brahmaputra valley are prone to earthquakes.

38) Which of following is not a type of earth quake waves?

a) P Waves

b) N Waves

c) L waves

d) S waves

Explanation: There are three types of earthquake waves: 1. P waves or longitudinal waves 2. S waves or transverse waves 3. L waves or surface waves

39) _______a vent or an opening in the earth’s crust through which hot magma erupts from deep below the surface.

a) Mountains

b) Lava

c) Volcanoes

d) Earthquakes

Explanation: A volcano is a vent or an opening in the earth’s crust through which hot magma erupts from deep below the surface. Th e opening is usually circular in form.

40) The Latur earthquake happened in the year?

a) 1991

b) 1993

c) 1999

d) 2003

Explanation: Th e Deccan Plateau, which was supposed to be comparatively free from the dangers of the earthquakes, has experienced two severe earthquakes in the past, the Koyna earthquake in 1967 and the Latur earthquake in 1993.

41) The molten rock material within the earth, together with gases, is called

a) Lava

b) Vent

c) Crater

d) Magma

Explanation: Molten rock material within the earth, together with gases, is called magma.

42) Magma Rises to the surface and it forms

a) Lava

b) Vent

c) Crater

d) Volcanoes

Explanation: The molten rock material within the earth, together with gases, is called magma. After it rises to the surface, it is called as lava.

43) If the crater of a volcano is of great size and is shaped like a basin it is called

a) Cratera

b) Caldera

c) Vent

d) Volcanic basin

Explanation: If the crater of a volcano is of great size and is shaped like a basin it is caldera

44) The scientific study of volcanoes are called

a) Volcanists

b) Volcanology

c) Lavalogism

d) Meganology

Explanation: The scientific study of volcanoes are called volcanology. People who study volcanoes are called volcanologists.

45) ______has only active volcano along the chain from sumatra to Myanmar

a) Barren Island

b) Sumatra Zone

c) Mandalay

d) None of above

Explanation: Barren island is situated in the Andaman Sea, and lies about 138 km northeast of the territory’s capital. It is only in active volcano along the chain from sumatra to Myanmar. Last eruption occurred in 2017.

46) Which of following is not a type of Volcanoes?

a) Shield Volcano

b) Cinder Cone Volcano

c) Composite Volcano

d) Sharp Volcanoes

Explanation: The shape of a volcano depends on the type of lava and the force of the eruption. On the basis of shape, there are three types of volcanoes. They are: 1. Shield volcano 2. Cinder-cone volcano 3. Composite volcano.

47) ______ world’s biggest active volcano

A) Mt. Popa

B) Mt. Etna

C) Mauna Loa

D) Mt. Hawaii

Explanation: Th ere are about 600 active volcanoes in the world, such as Mt. Stromboli in Mediterranean Sea, St. Helens in USA, Pinatubo in Philippines. Mauna Loa in Hawaii (3,255m.) is the world’s biggest active volcano.

48) _______is known as the ‘light house of Mediterranean sea

a) Napoli

b) Stramboli

c) Venice

d) Bologna

Explanation: Stramboli is known as the ‘light house of Mediterranean sea.

49) How many major zones of volcanic activities in the world?

a) 2

b) 3

c) 5

d) 6

Explanation: There are three major zones of volcanic activities in the world. They are: 1. The Circum – Pacific belt 2. The Mid continental belt 3. The Mid Atlantic belt.

50) The pacific ring of fire is estimated to have_____ of worlds active volcanoes.

a) 1/3rd

b) 2/3rd

c) 3/4 th

d) Half

Explanation: Circum belt includes the volcanoes of the eastern and western coastal areas of Pacific Ocean. This zone is popularly termed as the Pacific Ring of Fire which has been estimated to include two-thirds of the world’s volcanoes.