2nd Class EVS The Solar System The Sun

     The Sun

Sun is the biggest and hottest body in our solar system. Every planet in our solar system revolves around the Sun and all planet revolve on a fixed path which is called orbit. Sun is made up of helium and hydrogen gas. A small part of Sun is made up of oxygen, carbon, neon and iron. The core of the Sun is hottest as compare to the upper surface. Light radiated by the Sun contains ultraviolet rays which is dangerous for the living organism. Ozone layer around the earth stop the ultraviolet rays for survival of living organism. Our earth is far away from the Sun. Hence Sun's rays take 8 minutes to reach on to the earth, from the Sun.

Look at the following picture of the Sun:

      The approximate time taken by the light from the Sun to reach on the earth is:

(a) About 2 minutes

(b) About 8 minutes

(c) About 5 minutes  

(d) About 3 minutes

Answer: (b)

Explanation 

Light from the sun takes 8 minutes to reach on to the earth. Therefore, option (B) is correct and rest of the options is incorrect.

       Which one of the following is correct about the Sun?

(a) It is made up of helium only

(b) It is made up of hydrogen only

(c) It is made up of oxygen only

(d) It is made up of mainly hydrogen and helium

Answer: (d)

Explanation

Most part of the Sun is made up of helium and hydrogen and a small part is made up of oxygen and iron. Therefore, option (D) is correct and rest of the options is incorrect.