As per the figure given in question, we are considering it an Isosceles Prism.
Deviation is minimum in a prism when :
i=e,r1=r2 and ray (2) is parallel to base of prism.
The angle of deviation through a prism is minimum when JEE Main 2021 Physics, Ray Optics — question figure (A) Incident ray and emergent ray are…
JEE Main 2021 — Physics Optics
2021mcqeasy
The angle of deviation through a prism is minimum when
(A) Incident ray and emergent ray are symmetric to the prism
(B) The refracted ray inside the prism becomes parallel to its base
(C) Angle of incidence is equal to that of the angle of emergence
(D) When angle of emergence is double the angle of incidence
Choose the correct answer from the options given below :
Official previous-year question
Held on 16 Mar 2021 · Verified 6 Jul 2026.
Options
- A
Statements (A),(B) and (C) are true
- B
Only statement (D) is true
- C
Only statements (A) and (B) are true
- D
Statements (B) and (C) are true
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