⚛️ Physics · Ray Optics and Optical Instruments · NEET & JEE

For an equilateral prism (A=60 deg, n=sqrt(3)) in minimum deviation condition, angle of incidence:

Answer: 60 degrees.

A 30 degrees
B 45 degrees
C 60 degrees
D 75 degrees

Correct answer: C. 60 degrees

Explanation: At minimum deviation: r = A/2 = 30 deg. n = sin(i)/sin(r). sqrt(3) = sin(i)/sin(30) = sin(i)/0.5. sin(i) = sqrt(3)/2. i = 60 degrees.

Concave mirror ray diagram with an object drawn as a candle on the principal axis, the focal point F marked, and the parallel ray and focal ray reflecting to form an inverted real image

Concave mirror ray construction: a ray parallel to the axis reflects through F, and a ray through F reflects parallel, locating the inverted real image. Image: Maxmath12, CC0, via Wikimedia Commons.

Concept context

Reflection, refraction, lenses, mirrors, total internal reflection.

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For an equilateral prism (A=60 deg, n=sqrt(3)) in minimum deviation condition, angle of incidence:

Concept context

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