1st Class EVS Our Universe

   Thu Sun

 

Like water and air, the Sun is also a natural source of energy.

• The Sun is spherical in shape.
• It is the in center of our solar system.
• It is much larger than the Earth and the Moon.
• It is the ultimate source of energy.
• Life cannot be possible without the Sun.
• Plants use solar energy for making their food.

 

     Let us see the picture of the sun:

   

 

      Importance of Sun

• Sunlight is essential for living things.
• Plants get energy from the Sun to grow.
• Living things get heat from the Sun.
• Solar energy is used for heating, cooking, lighting etc.

 

    Negative Aspects of Sun

• Sun is unpleasant in summer.
• Over exposure to Sun causes sunburn.
• Heat waves in summer may cause sunstroke.
• Dehydration (loss of water from body) is common in summer, because Sun's heat.

 

 

 

  Which one of the following is true about the Sun?

(a) The Sun is seen at night

(b) The Sun is seen during day time

(c) The Sun is smaller than the Earth

(d) The Sun is not a natural source of energy

 

Answer: (b)

Explanation

Option (B) is correct. Therefore, rest of the options is incorrect.

  

 

  The shape of the Sun is _____.

(a) Spherical                                                       (b) Quadrilateral

(c) Cube                                                               (d) Square

 

Answer: (a)

Explanation 

Option (A) is correct, because the Sun is spherical in shape. Therefore, rest of the options is incorrect.

    The Moon

• It is a celestial body .which appears of same size as Sun in the sky.
• But it is smaller than both the Earth and the Sun.
• It is a part of our solar system.
• It is a heavenly body that moves around the Earth.
• It has spherical shape.
• It takes light from the Sun to glow.
• It can be clearly seen at night only.
• It is the natural satellites of the Earth.

 

 

  Moon is a _______body.

(a) Plastic                                                            

(b) Glass

(c) Heavenly                                    

(d) Soil

 

Answer: (c)

Explanation

Option (C) is correct, because the Moon is a heavenly body. Therefore, rest of the options is incorrect.

 

  When can you see the moon?

(a) Night                                                             

(b) Morning

(c) Midday                                                         

(d) Evening

 

Answer: (a)

Explanation

Option (A) is correct because, the Moon can be seen at night. Therefore, rest of the options is incorrect.

   The Planets

• They are the celestial or heavenly bodies, which form the part of solar system.
• They revolve around the Sun.
• They do not have the light of their own.
• They get light from the Sun.
• They are spherical in shape.
• They are of different sizes. Some are very big, such as, Jupiter. Some are small, such as. Mercury.
• But all of them are smaller than Sun. 

 

   Types of Planets

1. Terrestrial: They have a surface of solid rock.

2. Gas planets: They have surfaces of liquids or airy gas.

 

Our solar system has 8 planets, revolving around the Sun. Name of these planets, in order of increasing distance from the Sun, are given below:

1. Mercury  

2. Venus

3. Earth

4. Mars

5. Jupiter

6. Saturn

7. Uranus      

8. Neptune

 

• Out of these planets. Mercury, Venus, Earth and Mars are terrestrial or rocky planets.
• While Jupiter, Saturn, Uranus and Neptune are gaseous planets.
• The closest planet from the Sun is the Mercury.
• The hottest planet is Venus.
• The planet having life is Earth
• The red planet is Mars.
• The largest planet is Jupiter.
• The planet having ring around it is Saturn.
• The forest planet is Neptune.

 

 

 

  How many types the planets are?

(a) 8                                                                      

(b) 2     

(c) 4                                                                      

(d) 5

 

Answer: (b)

Explanation

Option (B) is correct, because planets are divided into terrestrial and gas planets. Therefore, rest of the options is incorrect.

 

 

Which one of the following planets are closest to the Sun?

(a) Mars                                                             

(b) Earth

(c) Venus                                                            

(d) Mercury

 

Answer: (d)

Explanation 

Option (D) is correct, because Mercury is the closest planets from the Sun. Therefore, rest of the options is incorrect.

      The Stars

• They are balls of gases, consisting mainly of hydrogen and helium.
• They glow and generate heat.
• They are celestial or heavenly bodies like Sun.
• There are countless numbers of stars in the universe.
• They can live for billions of years.
• Larger stars have shorter life.
• Bigger stars burn hotter and faster than smaller ones.
• Stars in the group of more than two are called constellations.
• Sun is a star, which is nearest to us.
• Stars are seen at night except the Sun.

 

Let us see the pictures of star:

 

 

  Which one of the following is the true statement?

(a) The Sun is not a star                                

(b) The Sun is a star

(c) Stars can be counted                              

(d) Stars are not heavenly bodies,

 

Answer: (b)

Explanation

Option (B} is correct, because this is an established fact. Therefore, rest of the options is incorrect.

 

 

The stars are balls of__________.

(a) Solids                                             

(b) Plastics

(c) Liquids                                           

(d) Gases

 

Answer: (d)

Explanation

Option (D) is correct, because stars .are made up of gases, Therefore, rest of the options is incorrect.

 

 

Moon is moving slowly away from the earth.

The Sunlight takes nearly eight minutes to reach the earth surface.

 

 

The Sun, the Moon, the Planets and the Stars are celestial or heavenly bodies.

The Sun is the hot spherical star.

Sunlight is the ultimate source of energy.

There are 8 planets revolving around the Sun.

Stars are made up of gases.

Stars can produce heat and light of their own.

Sun is the only star to be seen during day time.