Table of contents |
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Multiple Choice Questions |
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Fill in the Blanks |
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True or False |
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Match the Following |
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Multiple Choice Questions
(i) What is the outer layer of the Earth called?
(a) Mantle
(b) Core
(c) Crust
(d) Atmosphere
Ans: (c) Crust
The outer layer of the Earth is called the crust. It is the surface on which we live, and it varies in thickness from about 5 kilometers beneath the ocean floors to approximately 70 kilometers under the continents.
(ii)Which gas is NOT a main component of the Sun?
(a) Hydrogen
(b) Helium
(c) Oxygen
(d) Nitrogen
Ans: (c) Oxygen
The main elements that make up the Sun are hydrogen and helium. Oxygen is not a significant component of the Sun's composition, which primarily consists of hydrogen undergoing fusion into helium in the core.
(iii) How thick is the Earth's crust beneath the ocean floor?
(a) 5 kilometers
(b) 30 kilometers
(c) 70 kilometers
(d) 2900 kilometers
Ans: (a) 5 kilometers
The Earth's crust under the ocean floor is mentioned to be about 5 kilometers thick, much thinner than the crust under the continents.
(iv) What causes high tides in the ocean?
(a) Sun's heat
(b) Moon's gravity
(c) Wind patterns
(d) Earth's rotation
Ans: (b) Moon's gravity
High tides in the ocean are primarily caused by the Moon's gravity. The gravitational pull of the Moon on the Earth's oceans causes the water to bulge towards the Moon, resulting in high tides
(v) Which is the first artificial satellite launched by India?
(a) GSAT-15
(b) Aryabhata
(c) EDUSAT
(d) Chandrayaan-1
Ans: (b) Aryabhata
Aryabhata was India’s first satellite, launched in 1975. It marked India's entry into space operations.
Fill in the Blanks
(i) The ______ is the hottest part of the Sun.
Ans: core
(ii) The Moon takes about ______ month to go around the Earth.
Ans: one
(iii) The ______ is the layer of air that surrounds the Earth.
Ans: atmosphere
(iv)The Earth's crust can be as thick as ______ kilometers under the continents.
Ans: 70
(v) _________ are used for weather forecasting and transmitting signals.
Ans: Artificial satellites
True or False
(i) The inner core of the Earth is made up of liquid iron and nickel.
Ans: False
The inner core of the Earth is composed mainly of iron and is solid, not liquid. The outer core, however, is composed of liquid iron and nickel.
(ii) The Moon has its own light source.
Ans: False
The Moon does not have its own light source. It shines by reflecting the sunlight that falls on its surface.
(iii) A total solar eclipse occurs when the moon completely blocks the sun.
Ans: True
A total solar eclipse happens when the Moon comes between the Sun and the Earth, completely blocking the Sun's light from reaching Earth.
(iv)Tides are affected only by the moon's gravity.
Ans: False
While the Moon's gravity is the primary cause of tides, the Sun also influences tides. When the Sun, Earth, and Moon align, the gravitational forces of the Sun and Moon combine to produce spring tides, which are higher than normal.
(v) The corona is a thick layer of air around the sun.
Ans: False
The corona is not a thick layer of air; it is a thin outer layer of the Sun's atmosphere, visible during a total solar eclipse, extending millions of kilometers into space and very hot.
Match the Following
Column A | Column B |
1. Lunar Eclipse | A. Man-made object orbiting Earth |
2. Core | B. A phase where the Earth is between the Sun and Moon |
3. Artificial Satellite | C. The innermost layer of the Earth |
4. Tides | D. The rise and fall of ocean water levels |
5. Apollo 11 | E. First spacecraft to land on the Moon |
Ans:
1 - B: A lunar eclipse occurs when the Earth is between the Sun and Moon.
2 - C: The core is the innermost layer of the Earth.
3 - A: An artificial satellite is a man-made object orbiting Earth.
4 - D: Tides refer to the rise and fall of ocean water levels.
5 - E: Apollo 11 was the first spacecraft to land on the Moon.
(i) What is the core of the Sun responsible for?
Ans: The core of the Sun is responsible for nuclear fusion, where hydrogen atoms combine to form helium, releasing a significant amount of energy in the form of heat and light.
(ii) Describe the internal structure of the Earth.
Ans: Earth's internal structure is divided into three main layers: the crust, the mantle, and the core. The crust is the outermost layer, followed by the mantle which is divided into an upper and lower mantle with varying characteristics of rock. The core is split into an outer liquid layer and a solid inner core, primarily composed of iron and nickel.
(iii) How do tides occur due to the Moon?
Ans: Tides are caused by the gravitational pull of the Moon on Earth's oceans. The water is pulled towards the Moon, causing high tides, while on the opposite side of Earth, inertia causes water to bulge outward, also creating high tides.
(iv) What are the effects of a solar eclipse?
Ans: During a solar eclipse, when the Moon passes between the Sun and Earth, it blocks sunlight from reaching Earth. This causes a temporary darkening of the sky and cooling of the atmosphere in the path of the eclipse.
(v) What is the significance of Chandrayaan-1?
Ans: Chandrayaan-1 was India's first mission to the Moon, launched to map and study the Moon's surface. It significantly contributed to the understanding of the Moon's resources, discovering water molecules in the lunar soil.
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1. What are the main differences between Earth and its natural satellites? | ![]() |
2. How do natural satellites affect the Earth? | ![]() |
3. What is the significance of studying Earth's natural satellites? | ![]() |
4. How do natural satellites form? | ![]() |
5. What are some examples of natural satellites in the solar system? | ![]() |