δmin=2i−A
A=2i−A
A=i
μ=sin(2A)sin(2δmin+A)=sin(2A)sin(A)=sin30∘sin60∘
μ=3
v=μc=33×108ms−1
t=vAP=(33×108)53×10−2=5×10−10s
So, x=5
Cross-section view of a prism is the equilateral triangle ABC shown in the figure. The minimum deviation is observed using this prism when the angle…
JEE Main 2021 — Physics Optics
2021integerhard
Cross-section view of a prism is the equilateral triangle ABC shown in the figure. The minimum deviation is observed using this prism when the angle of incidence is equal to the prism angle. The time taken by light to travel from P (midpoint of BC) to A is ___________ ×10−10s. (Given, speed of light in vacuum =3×108ms−1 and cos30∘=23)
Official previous-year question
Held on 31 Aug 2021 · Verified 6 Jul 2026.
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