Study the following ray diagram: 

Question 15 [OD, Set-1, 2017].jpg

In this diagram, the angle of incidence, the angle of emergence and the angle of deviation respectively have  been represented by:  

(a) y, p, z 

(b) x, q, z  

(c) p, y, z 

(d) p, z, y 





  • Angle of incidence is the angle between incident ray and normal.
    Here, incident ray is on the right side (check arrows).
    So, here angle of incidence is angle p

  • Angle of emergence is the angle between emergent ray and normal.
    Here, emergent ray is on the left side (check arrows).
    So, here angle of emergence is angle y

  • Angle of deviation is the angle between emergent ray and incident ray (when produced backwards).
    So, here angle of deviation is angle z

Labelled figure for Refraction through a glass prism.jpg

So, the correct answer is (c) - p, y, z

  1. Class 10
  2. Chapter 10 Class 10 - Light - Reflection and Refraction (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