More Questions and Answers from the Seasons and Time (Class 10)

 1. The availability of solar energy in the earth is not alike. Explain the reason.

This happens due to the revolution of the earth around the sun on an inclined axis. In each and every latitude, in between the Tropic of Cancer and Tropic of Capricorn, the sun rays are falls horizontally.
2. Analyse the given picture and complete  the table.

3. Analyse the picture and Complete the table.

4. Why is the International Date Line not straight unlike the other longitudes?
There is a difference of 24 hours, between the two parts of the International Date Line. So it passes through the land area if the same place records two different times with 24 hours difference.
To solve this problem, the adjustments have been made avoiding the land areas and draw it into the sea.
The line is so arranged as to avoid some of the islands to the south of the Bering Strait in the Pacific Ocean.
5. Explain the reasons for the occurrence of seasons?
$  Rotation of the Earth. 
$  Tilt of the earth’s axis. 
$  Parallelism of the earth’s axis.
6. What is meant by the parallelism of axis?
The axis of the earth is tilted at an angle of 66½0 from the orbital plane. If measured from the vertical plane this would be 23½0. The earth maintains this tilt through out its revolution. This is known as the parallelism of the earth’s axis.
7. What is meant by leap year?
Earth takes 365 days and 6 hours to complete a revolution. Out of this 365 days are counted as one year. The remaining 6 hours of four continuous years added to the last year and those 24 hours is considered as the 29th day of the February of the fourth year. Thus the total days of such year has 366 days. That year is known as leap year.
8. What is meant by Equinoxes?
During revolution the position of the sun falls directly above the equator on March 21, and September 23. Hence the length of the day and night will be equal during these days on both the hemispheres. These days are called equinoxes.
9. Following are a few natural phenomena occur during different seasons in India. Identify the season represented by each.
a.  Sprouting and blooming of plants and trees.
b.  Trees shed their leaves.
c.  Drying of reservoirs.
d.  Dry atmosphere and low temperature.
Ans:
a. Spring b. Autumn
c. Summer d. Winter
10. There is an increase in time towards the east and decrease in time towards the west of all the longitudes other than 180° longitude. Why?
Ans:
•  The earth rotates from west to east.
•  So the sun rises in the east and sets in the west.
•  Hence there is increase in time towards the   east and decrease in time towards the west.
11. Which among the following longitudes is drawn deviated to avoid the land areas?
a.  Equator b. Greenwich meridian
c.  International Date line
d. 82½° East longitude
Ans: c. International Date Line
12. Why do certain countries consider more than one longitude as their standard meridians? Give an example for such a country.
Ans:  It is not practical to follow only one standard time for the countries with wide longitudinal extent. So more than one longitudes are considered as standard meridians. Eg: Russia, China, USA.