Which of the following phenomena contributes significantly to the reddish appearance of the sun at sunrise or sunset?

(a) Dispersion of light

(b) Scattering of light

(c) Total internal reflection of light

(d) Reflection of light from the earth

 

Answer

The sun appears to be red at sunrise and sunset because Earth’s atmosphere scatters the colours of the white light from the sun.

The colours we see are the ones left after the scattering. The phenomenon is called Rayleigh Scattering. 

  • Rayleigh scattering is inversely dependent upon wavelength.

Which of the following phenomena contributes significantly to the reddish-01.jpg

  • The colours with the smaller wavelengths are scattered more. 
  • At sunrise and sunset ,  violet, blue , green, and yellow colors are scattered through the atmosphere. 
  • The light has to travel a longer distance , so more colors are scattered
  • The red light reaching our eyes makes the sun appear red.  

rayleigh scattering- why the sky is blue-01.jpg

So, the correct answer is (b)

  1. Class 10
  2. Chapter 11 Class 10 - Human Eye and Colourful World (Term 1)

About the Author

CA Maninder Singh's photo - Founder at Teachoo
CA Maninder Singh
CA Maninder Singh is a Chartered Accountant for the past 11 years and a teacher from the past 11 years. He teaches Science, Accounts and English at Teachoo