6th Class NCERT Geography Chapter 3 Notes

 6th Class NCERT Geography  Chapter 3 Notes 

Motions Of The Earth 

1. Two types of Motions 

• Rotation 
• Revolution 

2. What is Rotation? 

Movement of the earth on it's Axis. 

3. What is Revolution? 

The movement of the earth around the sun in a fixed path or orbit is called Revolution.

4. The plane formed by the orbit is known as the orbital plane. 

5. What is Circle Of Illumination? 

• The circle divides the day from night on the globe is called circle of illumination. 

6. The Earth takes about 24 hours to complete one rotation around its axis.

7. The Period of rotation is known as the Earth day, this is daily motion of the earth.

8. What Happen If The Earth Did not Rotated ? 

• The portion of the earth facing the sun would always experience day. 
• continuous warm feel.
• The other half would remain in darkness and  be freezing cold all the time.
• Overally life would not have been possible in South extreme conditions.

9. The earth is going around the sun in an elliptical Orbit.

10. Season change due to the changes in the position of the earth around the sun.

11. Revolution 

• The Second motion of the earth around the sun in a fixed path orbit is called revolution.
• It takes 365 days and 6 hour to revolve around the sun.
• we consider a year as a consisting of 365 days only and ignore 6 hours for the sake of convenience. 
• 6 hours saved every year are likely to make one day over a spam of four years.
• This surplus day is added to the month of February. 
• Every fourth year February is of 29 days instead of 28 days. This  year with 366 days is called leap year. 

12. The nights are longer than the days in winter season. This position  of the earth is called as  summer solstice. 

13. On 22 December the Tropic of Capricorn get direct rays of the sun at the South Pole till towards it. It is summer in Southern hemisphere and winter in Northern hemisphere. This is called Winter Solstice. 

14. On 21st March and the 33rd September direct rays of the sun fall directly on the equator. During this period the whole Earth experience equal days and equal nights. This is called equinox.