NCERT Solutions for Class 6 Social Science Geography Chapter 3 Motions of the Earth

Q 1- Answer the following questions briefly.

(a) What is the angle of inclination of the earth’s axis with its orbital plane?

Ans :  The angle of inclination of the earth’s axis with its orbital plane is 66½o.

(b) Define rotation and revolution.

Ans :  Rotation – Movement of the earth on its axis is called rotation.

           Revolution – Motion of the earth around the sun in its orbit is called revolution.

(c) What is a leap year?

Ans :  The year having 366 days count is a leap year. It repeats every four year.

(d) Differentiate between the Summer and Winter Solstice.

Ans :

Summer Solstice

• Occurs on 21st June

• It is summer in the Northern and winter in the southern Hemisphere.

Winter Solstice        

• Occurs on 22nd December

• It is summer in the southern and winter in the Northern Hemisphere.

(e) What is an equinox?

Ans : On 21st March and 23rd September, sun rays directly fall on the equator due to which both the Northern and the Southern Hemisphere experiences equal days and nights, which is called equinox.

(f) Why does the Southern Hemisphere experience Winter and Summer Solstice in different times than that of the Northern Hemisphere?

Ans :      The southern Hemisphere experience winter and summer solstice in different times than the Northern Hemisphere due to inclination of the earth on its axis.

(g) Why do the poles experience about six months day and six months night?

Ans :      The poles experience about six months day and six months night because of the tilt of the earth on its axis.

v              Because of this tilt, each pole is tilted towards and away from the sun for about six months each.

v              When the North Pole is tilted towards the sun, it experiences continuous daylight for six months and vice-versa.

Q 2-  Tick the correct answers.

(a)         The movement of the earth around the sun is known as

                (i) Rotation         (ii) Revolution                    (iii) Inclination

Ans :      (ii) Revolution

(b)          Direct rays of the sun fall on the equator on

                (i) 21 March        (ii) 21 June                          (iii) 22 December

Ans :      (i) 21 March       

(c)           Christmas is celebrated in summer in

                (i) Japan               (ii) India                                (iii) Australia

Ans :      (iii) Australia

(d)          Cycle of the seasons is caused due to

                (i) Rotation         (ii) Revolution                    (iii) Gravitation

Ans :      (ii) Revolution

Q 3- Fill in the blanks.

(a) A leap year has _______________ number of days.

(b) The daily motion of the earth is _______________.

(c) The earth travels around the sun in ______________ orbit.

(d) The sun’s rays fall vertically on the Tropic of ___________ on 21st June.

(e) Days are shorter during ___________ season.

Ans :     

(a)          366

(b)          Rotation

(c)           elliptical

(d)          cancer

(e)          winter