New Longman Vistas 6
Social Science(Geography)
Chapter 1- The Earth in the solar system
(Solutions)
Exercise A(Choose the correct option)
1. (c) 6000 0C
2. (b) Mars
3. (b) Venus
4. (d) 76 years
Exercise B(True or False)
1. True
2. False(Sunlight takes 8 minutes to reach the earth surface)
3. False(The star nearest to the sun is Proxima Centauri)
4. True
Exercise C(Fill in the blanks)
1. Jupiter
2. Orbit
3. Inner planets
4. Vesta
Exercise D
Q.1. Whate are celestial bodies?
Ans. All the objects that we see in
the sky are called celestial bodies or heavenly bodies. These celestial
bodies include stars, planets, satellites, asteroids, meteoroids
and comets.
Q.2. To which galaxy does our solar system belong?
Ans. The Milky Way is the galaxy
that contains our solar system. It is also known as Akash Ganga. The
word 'milky' signifies a bright band of light in the night sky where
it is almost impossible to distinguish between stars.
Q.3. Which are the two types of
movement of the planets?
Ans. Planets have two types of
movement: rotation and revolution.
1. Rotation is the movement caused when a planet rotates on its axis;
for example, the Earth rotates from west to east on its axis.
2. Revolution is the movement when a planet revolves around the Sun in a fixed
path. The path of revolution of each planet is either egg-shaped or elliptical;
this path is known as an orbit.
Exercise E
Q.1. What are asteroids?
Ans. Apart from stars, planets and
satellites, there are several other tiny bodies that move around the
Sun. These bodies are known as asteroids. They are found between the
orbits of Mars and Jupiter. The largest known asteroid is named Ceres.
Q.2. How is a meteor formed?
Ans. Meteoroids are the small pieces
of rocks that revolve around the sun. some of these particles enters the earth’s
atmosphere with great velocity(speed).Due to friction with the atmosphere they
get heated up and start glowing. Most meteors burn out and some are quite large
and fall on the earth’s surface creating a crater(hole).They are then called meteorites.
Q.3. What are periodical comets? Give an example.
Ans. Periodical comets are the
comets that orbit around the Sun and return to the innermost point of
their orbits after a regular interval of time. A good example of a periodical
comet is Halley's Comet, which returns to its original position after 7576 years.
Q.4. Why is there no life on the moon?
Ans. There is no possibility of life on the Moon because of the
absence of the essentials of life on it, i.e. air and water. Also,
there is no atmosphere around it, due to which days are very hot and
nights are very cold. This makes the conditions unfavourable for the existence of
life on the Moon.
Exercise F
Q. Differentiate between star and a planet.
|
Stars |
Planets |
|
Stars are celestial
bodies made up of gases; they are huge in size and have very high
temperatures. |
Planets are the
celestial bodies that do not have their own heat and light. |
|
They have their own
heat and light, which they emit in large amounts. |
They are lit by the
light of stars. |
|
For example, the Sun
is a star. |
For example, the Earth
on which we live is a planet. |
Exercise G
Q. Why do we always see the same side of the moon ?
Ans. The Moon takes 27 days and 8
hours to revolve around the Earth. This period coincides with the rotation
period of the Earth on its axis, i.e. 24 hours. This is the reason we always
see the same side of the Moon.
