Q. The amount and the intensity of insolation vary during a day, in a season and in a year. Which of the following factors are influences the insolation?
1. The rotation of the earth
2. The angle of inclination of the sun’s rays
3. The transparency of the atmosphere
4. The configuration of land
Select the correct answer using the codes given below:

[A] 1, 2 and 3 only

[B] 1, 3 and 4 only

[C] 2, 3 and 4 only

[D] 1, 2, 3 and 4

Answer: D
Notes:

The amount and the intensity of insolation vary during a day, in a season and in a year. The factors that cause these variations in insolation are:  

  • the rotation of earth on its axis;  
  • the angle of inclination of the sun’s rays;  
  • the length of the day;  
  • the transparency of the atmosphere;  
  • the configuration of land in terms of its aspect. 

Source: NCERT Fundamentals of Physical Geography